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Eocyzicus parooensis Richter & Timms 2005, n.sp.
No full textEocyzicus parooensis n.sp. Figs. 1–3 Eocyzicus sp. a, Timms & Richter, 2002. Limnadia sp. b, Timms, 1993. Type material. HOLOTYPE 3, formalin-fixed AM P68156, carapace 7.8 × 4.5 mm. PARATYPES formalin-fixed: 13 slide AM P68157, 1♀ slide AM P68158; 833, 9♀♀, AM P68159, all collected by B. V. Timms from Gidgee Lake, 17 November 1999. Type locality. Gidgee Lake on Bells Creek, Bloodwood Station, 130 km NW of Bourke, NSW, Australia, 29°33'S 144°52'E. Etymology. This species is named after the Paroo area where it occurs commonly in hyposaline waters. Description. Male carapace 7.2 to 7.8 mm length, 4.2 to 4.5 mm height (n = 10). Female carapace 6.4 to 6.7 mm length, 3.9. to 4.1 mm height, smallest and largest female both ovigerous (n = 10). Carapace in both sexes oval, with 10 to 11 growth lines in males, and 9 to 10 in females. Dorsal margin of carapace with prominent umbo, posterior of umbo straight. Male head region with prominent rectangular (hatchet-like) rostrum in lateral view (Fig. 2A), including bilateral anterior margins, a ventral margin and a posterior margin. Anterior margins together form a V-shape in the dorsal view, continuing into the fornices of both sides (Fig. 2B). Nauplius eye triangular shaped, with sharp end pointing to the compound eye. Central dorsal part of the head defined anteriorly by prominent compound eye chamber and posteriorly by rounded occipital condylus. Compound eye chamber opening via a small pore anteriorly, slightly above anterior margins of rostrum (Fig. 2A, arrowhead). Central head region filled by mid-gut diverticula. Dorsal organ located close to posterior margin of occipital condyle (Fig. 2B, arrowhead). Female head region differing in particular by shape of rostrum which is more triangular because of less distinct posterior margin (Fig. 3A). Antennule extending to about fourth (females) or sixth (males) segment of posterior antennal flagellum, and distinctly lobate with each lobe bearing short sensilla (Fig. 2C). Antenna with peduncle of about eight segments, anterior densely covered with setae (Fig. 3C), and with about 11 to 14 segments on both anterior and posterior flagellum. Each flagellum segment bearing about six short spines on anterior side, and a number of longer natatory setae at the posterior side. Trunk consisting of 22 (in a few cases 23) leg-bearing segments, the last (two) segments not entirely separated from telson (Figs. 2G, 3B). More posterior trunk segments (between 10 and 15) carrying single dorsal spine at posterior end of segment (Fig. 2F). First and second thoracopod of male modified as claspers, not differing general characters from each other. Movable finger smoothly curving to the apical club (i.e. expanded apex). Surface of movable finger adjacent to apical club covered with scales; apical club with stout flat-tipped spines opposite to scales of movable finger (Fig. 2D). Tip of movable finger with about six (specimen studied might be broken in this area) more elongated “hairy” scales, directed away from apical club (Fig. 2E). Two palps originating from palm, the larger (threesegmented) palp behind movable finger, smaller (onesegmented) palp at apical club base. In females, eggs carried by projections of exopod of the ninth and tenth pairs of thoracopods (Fig. 3D). Telson covered dorsally by numerous spines, with caudal furcae originating at its posterior end. Dorsal part of telson formed like a “U”, with connecting part anteriorly and the two parallel margins ending in strong, upwards curved apexes (Fig. 2G,H,K). Margins carrying about 10 to 13 spines each in males and about 15 to 20 in females, excluding the apex (Figs. 2G, 3B). Two telsonal setae originating from a common plate at anterior end, at inner side of “U” (Fig. 2K). Caudal furcae articulated with telson; each carrying many (about 15) long plumose setae on inner margin (Fig. 2G,K). Tips of caudal furcae covered by very small spinules (Fig. 2 I). Eggs round and smooth, not showing any specialized surface structures (Fig. 3D). Remarks. This species has been recorded from several other localities in the Paroo area (Timms & Richter, 2002). Some of the characters differ from those described herein, e.g., the number of growth lines, number of telson spines, and the carapace length and height. Nevertheless, we believe that all these records (referred to in Timms & Richter, 2002 as Eocyzicus sp. a) are of E. parooensis n.sp. Most remarkable from an ecological point of view is that all these records are from hyposaline water bodies (see Timms & Richter, 2002 for more details). There is probably a second undescribed Eocyzicus species common in the Paroo area, which prefers turbid fresh water habitats (referred to Eocyzicus sp. b by Timms & Richter, 2002).Published as part of Richter, Stefan & Timms, Brian V., 2005, A List of the Recent Clam Shrimps (Crustacea: Laevicaudata, Spinicaudata, Cyclestherida) of Australia, Including a Description of a New Species of Eocyzicus, pp. 341-354 in Records of the Australian Museum 57 (3) on page 343, DOI: 10.3853/j.0067-1975.57.2005.1454, http://zenodo.org/record/468562
FIGURE 3 in A revision of the clam shrimp Australimnadia Timms and Schwentner, 2012 (Crustacea: Spinicaudata: Limnadiidae) with two new species from Western Australia
No full textFIGURE 3. SEMs of Australimnadia eggs. A–E: A. grobbeni (Daday, 1925). A, Knuckeys Lagoon, Darwin, NT; B, dune lake, Ussher Pt, Cape York, Qld; C, gilgai, Meandarra, Qld; D, pond, Taloumbi, NSW; E, swamp, Barmah Forest, Vic; F, Limnadia lenticularis Sars, North America. Scale bars 100 µm.Published as part of Timms, Brian V. & Schwentner, Martin, 2017, A revision of the clam shrimp Australimnadia Timms and Schwentner, 2012 (Crustacea: Spinicaudata: Limnadiidae) with two new species from Western Australia, pp. 81-98 in Zootaxa 4291 (1) on page 86, DOI: 10.11646/zootaxa.4291.1.5, http://zenodo.org/record/82938
Eulimnadia kimberleyensis Timms, 2018, sp. nov.
No full textEulimnadia kimberleyensis sp. nov. (Figs 1, 2). Etymology. This species is named for the area of Australia in which it occurs. Type material. Holotype. Female. Rock pool. Western Australia, Kimberley, Gardner Plateau, from 14o 47’ 2.1”S, 126o 31’ 18.9”E. Length 4 mm, height 3.1 mm (WAM C72086), coll A. Cross, March 2012. Paratypes. Two females. Lengths 4.0 and 3.9 mm (WAM C72087) from the same locality. Diagnosis. Egg spherical with about 36 grooves arranged randomly and about 30 µm long; walls of grooves thick and rounded with surface usually crenulated at right angles to groove axis. Female first antennae with about three lobes; second antennae with 7 antennomeres and generally 4–5 spines dorsally. Telson with about 19 dorsal spines and cercopod with about 8 long setae. Description. Egg (Fig 1A, B, C). Spherical, mean diameter 128 µm, range 122 to 134 µm, n = 10. Surface with about 36 (range 33–42, n = 10) grooves each about 30 µm long and arranged randomly. Tertiary layer represented by the apparent groove walls spongiform and thick and rounded, though surface usually crenulated at right angles to the major axis; sometimes a minor elevated area where walls of adjacent grooves confluent. In cross section, each groove—wall system consists of 80–90% wall and only 10–20% flat-floored groove with a distinct demarcation between the two. Female. Head (Fig. 2B) with ocular tubercle prominent, the compound eye occupying most (ca 80%) of it. Rostrum broadly rounded and protruding a little less than the ocular tubercle. Ocellus about as large as the compound eye and located in the middle base of the rostrum. Frons-rostrum angle about 150o. Dorsal organ posterior to the eye by about its height, pedunculated, asymmetrical and about half as high as the ocular tubercle. First antenna (Fig 2B) short, about 40% the length of the peduncle of the second antenna, and with three lobes, each with short sensory fine setae. Second antenna (Fig 2C) with 7 antennomeres, most (II to VI) with 4–5 short spines dorsally and 3–5 long setae ventrally. Basal antennomere with just 3 spines and a seta while distal antennomere with 2 spines and about seven setae. Carapace (Fig 2A) elongated oval with a vaulted dorsal and ventral edge and weak anterodorsal and posterodorsal angles. Abductor muscle scar at about 45o to carapace long axis. Carapace pellucid and without markings except for five growth lines, generally well spaced except near the ventral edge. Trunk of 18 segments. Dorsal surface of posteriormost 9–10 segments with many long two-segmented setae and sometimes shorter spines. Thoracopods of trunk segments IX and X with long epipods for retaining eggs. Telson (Fig 2D) with 9 dorsal spines followed by a large spiniform projection, the first spine about 20% larger than the next few followed by some variation in size and spacing along the row. Spines smooth. Telsonic filaments inserted on a mound between 2nd and 3rd spine. A moderate declivity posterior to the mound, remainder of telsonic floor sloping evenly and gently to cercopod base. Cercopod a little shorter than telson length and with a short spine about 80% along its length separating a thicker basal area supporting setae from a thinning distal area with a weak cirrus of small denticles. Short laminate spine with about 7 serrations on anterior surface and two small spines near the base. (see Fig. 2D insert). Eight long cercopod setae, their length about twice the basal diameter of the cercopod. Prominent spiniform projection on ventroposterior corner of telson. Variability. There are only three specimens available, so little can be added on variability of the above characters. Sometimes there are only six antennomeres though whether this is natural or damaged is not certain. Telsonic spines may number 8–10 and and cercopod setae 7–10. Differential diagnosis. There is no doubt this species belongs to the genus Eulimnadia. The diagnostic character is a spiniform projection on the ventroposterior corner of the telson (Rogers et al., 2012). In addition most Eulimnadia, including this species, have a spine on the cercopod at about 4/5ths its length and the antenna has about 7–8 antennomeres on each flagellum (Timms, 2016a). However, because of the limited number of specimens and lack of males the description of this species is minimal. Nevertheless species specific egg morphology in this genus (Belk, 1989; Rabet, 2010; Timms, 2016a) provides characters to separate species and in some cases is about the only distinguishing character, e.g. E. graniticola Rogers et al. 2010). However, for Australian species species specific egg morphology has been supported by features of the cercopods and sometimes a few other characters as well from the telson, claspers, antenna and head (Timms, 2016a). This dictum applies to this species. In this case the egg morphology is certainly the most distinguishing feature, though a combination of less important characters (a cercopod with 8 uniform setae, just nine unevenly spaced telsonic spines and a first antenna of just three lobes) help to define it. The most similar eggs are of E. beverleyae Timms, 2016 and E. uluruensis Timms, 2016. Eggs of E. beverleyae (Fig. 3F, Timms 2016a) have about 30 grooves, each about 40 µm long, and of the same tertiary material as their walls, whereas in E. kimberleyensis sp. nov. there are but 40 grooves, 40 µm long and of different tertiary material to that of the walls. In addition E. beverleyae has 11–13 cercopod setae whereas E. kimberleyensis sp. nov. has only about 8 cercopod setae. In E. uluruensis (Fig.9 H. Timms, 2016a) the grooves number about 28, lie within distinct polygons with low lateral ridges and a knobbly surface, a situation quite different to that in E. kimberleyensis sp. nov. (see above). Though E. uluruensis has telsonic spines reminiscent of E. kimberleyenesis sp. nov., the cercopod setae of E. uluruensis are shorter than those of E. kimberleyensis sp. nov. Given E. kimberleyensis sp. nov. lies within the distribution of the widespread and variable E. dahli Sars 1896, it is appropriate to detail their distinctiveness. Firstly, habitat choice is not distinctive— E. dahli occurs in gnammas in limestone in northwest Queensland (Timms, 2016a) and also in granite in the Pilbara (author unpublished data) while E. kimberleyensis sp. nov. occurs in sandstone gnammas in between these areas. However, their eggs are entirely different, those of E. dahli have ca. 20 surface polygons, while those of E. kimberleyensis sp. nov. have ca.36 grooves. Eulimnadia dahli typically (but not always) has 20 trunk segments, and E. kimberleyensis sp. nov. the standard 18. Furthermore E. dahli has ca. 15 telsonic spines and ca 18 cercopod setae, whereas E. kimberleyensis sp. nov. has ca 9 and 8 respectively, a difference wide enough to be certain of identity. Distribution. Known only from gnammas on the Gardner Plateau, Kimberley. These pools fill during the wet season, November to April, and the deeper pools (averaging 46 mm) support aquatic plants (Cross et al., 2015a, 2015b). No information is available on their fauna, except that a few pools support the new species of clam shrimp described here plus Limnadopsis multilineata Timms 2009.Published as part of Brian V Timms, 2018, Three new species of spinicaudatan clam shrimps from Australia, all from gnammas (rock pools), pp. 136-148 in Zootaxa 4418 (2) on pages 137-139, DOI: 10.11646/zootaxa.4418.2.3, http://zenodo.org/record/124533
Limnadopsis paradoxa Timms 2009, n.sp.
No full textLimnadopsis paradoxa n.sp. Figs. 2G, 4D, 5K,L, 13 Types. Holotype 3 WAM C39341, allotype ♀ WAM C39342, paratypes 23, 2♀, WAM C39343, 33, 2♀, AM P76808. Type locality: Western Australia, E of Grass Patch, Sieda Farm, Fitzgerald Paddock 81, temporary pool, 33°13'S 121°47'E, 2.ii.2007, B. V. Timms. Other material. Western Australia: 43, S of Newdegate, Lake Bryde, 33°21'S 118°49'E, 21.iii.2006, D. Cale, WAM C39344; c. 20 individuals, S of Newdegate, Lake Bryde East, 33°22'S 118°54'E, 21.iii.2006, D. Cale, WAM C39345; c. 20 individuals, SE of Salmon Gums, along Guest Rd, temporary pool in paddock, 33°06'S 121°46'E, 25.i.2007, B. V. Timms, WAM C39346;> 50 individuals, E of Grass Patch, Sieda Farm, Fitzgerald Paddock 81, temporary pool, 33°13'S 121°47'E, 2.ii.2007, B. V. Timms, WAM C39347;>50 individuals, SE of Scaddan, Truslove Nature Reserve, a paperbark swamp, 33°20'50"S 121°46'5"E, 27.i.2007, B. V. Timms, WAM C39348. South Australia: 13, N of Woomera, Olympic Dam, 30°28'S 136°44'E, 12.ii.1981, M.J. Tyler, SAM C6351. New South Wales: 13, near Wilcannia, roadside ditch 19.5 km east of town, 31°41'S 143°427'E, 14.i.2007, B. V. Timms. Habitat and distribution. Limnadopsis paradoxa lives in freshwater intermittent ponds and lakes, that are somewhat turbid or humic. More is known about the habitat of this new species than the others, because the author is personally familiar with the area. The ponds and lakes fill every few years and may take two or more years to dry (e.g., Lake Bryde, Cale et al., 2004) or dry within months (e.g., pools on Sieda Farm, A. Longbottom, pers. comm.). In all sites it was found only in the early period of inundation. It is known mainly from the southeastern wheatbelt of Western Australia, specifically south of Newdegate and north of Esperance. Two outlier populations were found much further east, in central South Australia and in southwestern NSW. In Lake Bryde, it was collected in March, 2006, six weeks after a major filling, and at the time the lake was fresh (EC 549 µS/cm), alkaline (pH 7.8), warm (21.8°C), well oxygenated (88% saturation), and only slightly coloured (D. Cale, pers. comm.) This lake fills to overflowing only occasionally (every few years in the 1990s to 2000s, S. Halse, pers. comm.); normally the episodic fillings result in a shallow, fresh to slightly saline lake that takes 12–24 months to dry. At such times it holds the clam shrimps Caenestheria sp. and Caenestheriella sp., but apparently not Limnadopsis paradoxa (Cale et al., 2004). In seven sites at Grass Patch it appeared as adults within three weeks of filling in late January, 2007. These ponds are c. 20–50 m in diameter, saucer-shaped and up to 2 m deep. They were once Melaleuca swamps, but many are now usually farmed for cereals. They fill partially, or deeply as in 2007, in wet summers, generally about once every 5–10 years (A. Longbottom, pers. comm.). Their water is humic (40–150 NTU), fresh (conductivity 260–440 µS/cm), warm (21–28°C), and acid to slightly alkaline (pH 5.8–7.4). By early March 2007, all of the ponds sampled had declining senescent populations, or none at all. Etymology. The species name derives from the paradox presented upon first examination: it has a carapace resembling L. birchii and a body-form superficially resembling L. tatei, but it differs from these two species on detailed examination. Male. Carapace (Fig. 13A) 14.6 mm long by 9.9 mm deep, L:D ratio c. 1.5. Dorsal margin doubly curved so lowest point at anterior umbo area and highest point about two-thirds of way along the hinge line. Hinge line uneven with growth lines protruding as small carinae, these generally more prominent posteriorly. Umbo humped dorsoanteriorly. Growth lines 12, expressed, crowded anteriorly, but more spaced spaced posteriorly. Carapace coloured dark humic brown. Head (Fig. 13B) with a pear-shaped pyriform frontal organ posteriorly, preceded by rounded prominence containing eye, then by large rostrum at right angles to head. Length of rostrum similar to length of anterior surface of head and about twice its own basal width. Rostrum curved downwards apically and containing triangular naupliar eye dipping at angle to rostrum axis and occupying much of its basal area. First antenna with 11 subequal lobes, slightly longer than peduncle of second antenna. Two flagella each bearing 15–18 beaded flagellomeres, each of latter with up to 6–7 spines evenly spaced along dorsal surface. Trunk segments 26. Dorsally, posteriormost segment with spineless protuberance, preceding 7–8 segments each with 3–5 spines on protuberance, then further anteriorly another 7 segments with 5–9 long setae each. Hand of claspers with blunt narrow outgrowth near inner basal corner. Third thoracopod (Fig. 4D) similar in structure to that of L. birchii. Proportions of endites, endopod, exopod and epipodite slightly different, and significantly palp of fifth endite slightly shorter than fifth endite and epipodite proportionally smaller. Other thoracopods of same basic structure, but without palp and with larger epipodite. Telson (Fig. 13C) with two rows of 13 to 14 strong, subequal spines, although the first spine slightly larger than next few spines and curving slightly posteriorly, middle spines slightly smaller and posterior spines more widely spaced, and sharper last spine near apex of claw. Two telsonic setae inserted on protuberance about one quarter of way along dorsal side of telson. Caudal claws well developed, at least twice as large as telsonic claws, curved concavely dorsally, with basal two-thirds bearing about 20 setae mesodorsally and terminating in a spine. Apical third of claw with many fine denticles dorsally. Female. Carapace (Fig. 13E) 13.5 mm by 9.7 mm. Similar to that of male, but anterior concavity less pronounced and highest point of carapace at about midlength. Carinae of growthlines prominent, but blunt compared with those of male. Head (Fig. 13F) similar to that of male, but rostrum short, about as long as deep, and blunt. Naupliar eye of about same size and position as in male, thus occupying much of rostrum. First antenna shorter than in male, with about 8 lobes. Second antenna as in male. Number of body segments, and details of telson (Fig. 13G) similar to those in male. Eggs (Figs. 4L,M) top-shaped, with prominences dorsal and ventral and about 5 prominences around equator. Typically about 16 grooves between equator and dorsal and ventral prominences, and about 3–4 grooves between each equatorial prominence. Ridges between grooves may be straightish or Y-shaped, the latter generally in the fields between equatorial and dorsal or ventral grooves. Sometimes only 4 equatorial prominences present and grooves somewhat randomly distributed. Maximum dimensions about 250 µm (range 241–254 µm, n = 20). Variability. The carapace size varies from c. 13 to16 mm, growth lines from 10 to 14, first antennal lobes 9 to 11, telsonic spines 15 to 18, and caudal claw setae from 16 to 21. There is no significant variation in the characteristic carapace shape, and all specimens have just one spine on the caudal claws. Comments. Limnadopsis paradoxa resembles small specimens of L. birchii, on account of its size, general shape, development of the carinae, and perhaps colouration. However, the body inside bears absolutely no resemblance to that of L. birchii. For instance there are 26 body segments, not 32, and there are only c. 14 telsonic spines on a almost straight edge compared to c. 50 spines on a doubly curved edge. The new species is most like L. tatei but has more growth lines, more lobes on the first antenna, more telsonic spines and more setae on the caudal claws. Perhaps it could be regarded as a bigger form of L. tatei, but the shape of the carapace is distinctive, particularly the concave dorsal surface and the lateral development of the umbo. The smaller first:second telsonic spine size ratio in L. paradoxa, and more numerous caudal claw setae are also distinctive. Limnadopsis pilbarensis n.sp. (see below) differs by having a convex edge in the umbo area, much less pronounced development of the dorsal outgrowths of the growth lines, and fewer telsonic denticles and setae on the caudal claws. The eggs of L. paradoxa and the three other abovementioned species are distinctive among themselves. At 40× magnification, eggs of L. birchii and L. tatei are smoothly round with groups of parallel grooves, more of the latter in L. birchii than in L. tatei. Eggs of L. paradoxa and L. pilbarensis both have rough surfaces, but those of L. pilbarensis have many (> 20) spines and those of L. paradoxa have just a few (<8) rounded prominences. These distinctions are even more pronounced as observed by SEM (Fig. 4).Published as part of Timms, Brian V., 2009, A Revision of the Australian Endemic Clam Shrimp Genus Limnadopsis Spencer & Hall (Crustacea: Branchiopoda: Spinicaudata: Limnadiidae), pp. 49-72 in Records of the Australian Museum 61 (1) on pages 65-66, DOI: 10.3853/j.0067-1975.61.2009.1498, http://zenodo.org/record/524026
Branchinella anatinorhyncha Timms, 2012, sp. nov.
No full textBranchinella anatinorhyncha sp. nov. Figs. 1 C, 2, 3 Etymology. The name is an amalgam based on latin ‘anatin’ meaning ‘duck’ and greek ‘rhynchus’ meaning ‘nose’ and refers to the frontal appendage having the form of a duck bill. Should this shrimp ever become known enough to have a common name, it would be the duckbilled fairy shrimp and hence analogous in the broadest sense to the duck-billed platypus, Ornithorhyncus anatinus. Type locality. Australia, Queensland, Sumana Station 74 km N of Aramac, an unnamed claypan 2 km E of homestead, 22 o 18 ’ 38 ”S, 145 o 23 ’ 08”E, 2 April 2009, collector M. Schwentner & BVT Holotype. Male deposited in Australian Museum (Sydney). Total length 11.9 mm. Accession number AM P 88368. Allotype. Female deposited in Australian Museum (Sydney). Total length 14 mm. Accession number, AM P 88369. Paratypes. Males and females deposited in Australian Museum (Sydney). Accession number, AM P 88370. Other material. 3 males, Australia, Queensland, Sumana Station 74 km N of Aramac, unnamed claypan 5 km NW of homestead, 22 o 16 ’ 40 ”S, 145 o 20 ’ 15 ”E, 28 February 2008, deposited in the collection BVT and in Australian Museum (Sydney); accession number AM P 88371. Diagnosis. Male with unbranched paddle like frontal appendage. Only frontal appendage adornment a minutely frilled edge on basal third of the wider portion. Second antenna with proximal antennomere’s distomedial corner with a small lobe bearing a few short setae. Description. Male. Eyes almost sphaerical, freely projecting on peduncles about the same diameter as the eye. First antennae filiform, about a third longer than second antenna proximal antennomere, terminating in 3–5 long sensory setae. Second antennae. Proximal and distal antennomeres subequal in length. Proximal antennomere cylindrical and with a small tumidity mediodistally bearing many small setae. Proximal antennomeres fused medially. Distal antennomeres evenly curved, narrowing distally and forming the claspers; apical half of claspers with distinct transverse ridges medially. Frontal appendage unbranched with a thick roundish pseudosegmented trunk supporting a long paddle-like blade, twice length of the trunk. Two vesicles lying adjacent in the trunk but divergent in the blade. Basal third of blade with a minutely frilled edge, otherwise edge and both surfaces of blade smooth. Blade apex squarish. Blade generally carried coiled in life, particularly lengthwise, but also across its width. Fifth thoracopod with endite 1 + 2 and 3 evenly curved, the former about three times the size of the later. Anterior setae of endite 1 smooth, a little more than half the length of adjacent posterior setae. Anterior setae of endite 2 half the length of endite 1, bearing a one-sided pecten of spines and attended at its base by a small smooth spine. Endite 3 with an anterior setae bearing one-sided pecten of spines and three times longer than anterior setae of endite 2. Endites 4–6 asymmetrical and covered with small spines. Endites 4 and 5 with two anterior setae and endite 6 with one anterior seta, each about twice the length of the anterior setae of endite 2. These setae of two types. Each endite with a seta of two equal length parts, a wide base with a few long strong spines on each side on proximal half of base and a thin apical part with thinner shorter spines on each side. The second type, on endites 4 and 5 only, of uniform tapering with a bare basal half and a distal half similar to distal half of the first setal type. Posterior setae of all endites long and numbering about 60 on endites 1 +2, 18 on endite 3, then 3, 2, 2 respectively on endites 4–6. Endopod broadly rounded and bearing about 32 spaced posterior feathered setae, those on the medial margin shorter (about same length as anterior setae of endites 4–6) than those on the remainder of the endopod. Exopod oval bearing about 40 posterior setae closely spaced and long and generally bent apically like those on the most of the endopod. Epipodite lanceolate and unadorned. Praeepipodite large and broad, about one and a half the size of endite 1 + 2, and with a smooth unadorned margin. Genital segments similar, gonopods short, about two-fifths the length of first abdominal segment and with a small lateral tumidity. Everted gonopod with a short row of about four triangular spines medially and a narrow field of longer thin spines on opposite side. Cercopods typical for the genus. Female. Eye plus peduncle elongated to be about two thirds second antenna length. First antenna filiform and subequal to second antenna length. Second antenna broad terminating to a symmetrical apex and a little longer than labrum. Fifth thoracopod and cercopods as in male. Genital segments larger than abdominal segments and with brood pouch bulbous anteriorly but tubular posteriorly and terminating between second and third abdominal segments. Egg diameter 169.5 µm and with about 50 irregularly shaped distinct depressions. Walls of depressions wide and rounded and floors flat and moderately dimpled (Timms and Lindsay, 2011). Size. Males range in size from 11.9–14.1 mm (n= 5) and females from 14.0– 14.1 mm (n= 2) so males and females about the same size. Variability. In the five males examined, the frilled edge on the base of the distal portion of the frontal appendage varied by about 10 % in the extent and size, with the holotype about average. The two proximal antennomeres sometimes appear fused at about 60 o instead of the more usual 80–90 o. Differential diagnosis. Branchinella anatinorhyncha sp. nov. differs from other species of Branchinella in its 16 SmtDNA by 4.6 % (Pinceel et al. 2012). Morphologically it is unlike any other species of Branchinella with its frontal appendage unbranched and paddle like. Moreover it has almost no adornments in the form of papillae or setae on its frontal appendage, thus further distinguishing from many species including B. macraeae Timms, B. affinis and those with ramified frontal appendages such as B. frondosa Henry and B. arborea Geddes. It is not unusual for species of Branchinella to have some kind of sensory apparatus on or near the mediodistal corner of the proximal segment of the first antenna (e.g. B. affinis, B, arborea, B. kadjikadji Timms, B. insularis Timms, B. macraeae, B. pinderi Timms), but the lobes bearing setae of B. anatinorhyncha sp. nov. are unique. Perhaps B. anatinorhyncha sp. nov. can be thought as related to B. affinis and associated species in which the frontal appendage instead of branching apically is undivided. Like many species of Branchinella, females lack unique characteristics. Distribution. So far this species is known only from claypans on Sumana Station, but it could well occur in claypans over a wider area north of Aramac/Muttaburra to south of Prairie in inland north Queensland. Resting eggs similar to those known to be B. anatinorhyncha sp. nov. have been found in claypans at Kooroorinya on the Muttaburra to Prairie Road (21 o 20 ’S, 144 o 40 ’E).Published as part of Timms, Brian V, 2012, Further studies on the fairy shrimp genus Branchinella (Crustacea: Anostraca: Thamnocephalidae) in Australia, with descriptions of five new species, pp. 35-60 in Zootaxa 3595 on pages 38-41, DOI: 10.5281/zenodo.25459
Parartemia bicorna Timms, 2010, sp. nov.
No full textParartemia bicorna sp. nov. (Figs. 4,7,8) Parartemia sp x, Timms et al., 2006, p 181, Table 5; Timms and Hudson, 2009, p 58. Etymology. The specific epithet, bicorna, celebrates the prominent twin anterior processes of the male, vaguely akin to the head spine of the fabled unicorn, but with two instead of one horn. These process are somewhat larger than in other known species of Parartemia; some like P. contracta may have longer processes, but these are generally narrow and bent, while those in P. b i c o r n a sp. nov. are straight and robust, and hence instantly noticeable. Holotype. Male, Lake Carey, 27.5 km south of Laverton, Wallaby Mine discharge, (28 o 52 ’ 03”S, 122 o 19 ’ 25 ”E), 11 March 2004, B. Timms, WAM 45214. Allotype. Female (ovigerous) same collecting data as holotype, WAM 45215, Paratypes. Two males and two females, same collecting data as holotype, WAM 45216; two males and two females, same collecting data as holotype, AM P 82973. Other material. Seven males, six females, Lake Carey, ‘Salinaland’ (ie.northeast corner), (28 o 49 ’ 58 ”S, 122 o 16 ’ 16 ”E), 11 March 2004, B.V. Timms, WAM 45217; ten males, ten females, Lake Carey, Causeway area, (29 o 18 ” 53 ”S, 122 o 34 ’ 05”E), 17 February 2006, B. Datson, WAM 45218; seven males, eight females, Lake Carey, inlet into ‘Salinaland’, (28 o 48 ’ 42 ”S, 122 o 15 ’ 6 ”E), B. Datson, WAM 45219; nine males, 2 females, Lake Carey, ‘Salinaland’ (ie.northeast corner), (28 o 49 ’ 58 ”S, 122 o 16 ’ 16 ”E), 6 December 2008, B. Datson, WAM 45220. Description. Male. Length 19.8 mm (head + thorax + genital segments 8.3 mm and abdomen 11.5 mm). First antenna (Fig 8 A) filiform, about twice as long as eye plus peduncle. Second antenna. Basal antennomere of second antenna (Fig 8 A) fused proximally at about right angles to body axis and protruding a similar width to first antenna. Ventral margin of second antenna with paired linear ventral processes (Fig 8 A) bearing numerous closely spaced minute denticles apically. Overall dimensions of these processes about 2.5 times longer than average width, with lateral edge about half length of medial edge. Lateral edge broadly rounded but medial edge folded anteriorly to about one fifth of ventral process length; fold widest at about two-thirds length of the ventral process. Medial edge of ventral process bulges into the medial space between the processes, maximally at about half its height. Posterior base of lateral edge of ventral process with an indistinct conical mound with a few small denticles. Medial process digitiform, length slightly less than half the height of the ventral process medial edge. Anterior surface of proximal antennomeres with a prominent conical anterior process (Fig 8 A) on each half, with a large free apical half about the length of the ventral process. Distal antennomeres (Fig. 8 A) of second antenna about twice length of basal antennomere, curved, with a mesial tumidity and tapering to a sharp apex. Labrum lacking a spine. Thoracic segments (Fig 8 B) with lateral lobes progressively increasing in size T 1 to T 11 and then with smaller lobes on the two genital segments. Eleven pairs of thoracopods, variable in size, with first two noticeably reduced in size and last few a little smaller. Fifth thoracopod similar to that of Parartemia longicaudata. Endite 1 + 2 with 1 + 2 anterior setae and ca. 25 posterior setae, endite 3 with 2 and ca 16 setae respectively, endite 4 with 2 and 3, endite 5 with 2 and 2 and endite 6 with 1 and 2 setae respectively. These setae of similar relative lengths to those of P. acidiphila (Timms and Hudson, 2009, Fig 2). Endopodite squarish with broadly rounded corners and bearing ca, 6 one-sided pectinate posterior setae medially and ca. 24 feathered posterior setae terminally and laterally. Exopodite elongate oval and bearing ca. 36 posterior setae, similar to most on the endopodite. All these posterior setae with a basal coronet of ca. 8 small spines. Epipodite oval shaped and praeepipodite elongated oval shaped, both unadorned. Gonopods (Fig 8 C) paired, basal parts fused together and about twice the diameter of apical free portions. Free apical part basally with a triangular process with an asymmetrical apex and a subapical digitiform process, about a third the length of the basal process. No type specimens with the gonopod everted. Abdominal segment s increasing in length and narrowing posteriorly from 1 to 6, particularly 5 and 6, so that last segment about twice the length of the first. Cercopods fringed with long setae on lateral and medial edges; length subequal to 6 th abdominal segment. Female. Length 14 mm (head + thorax+ genital segments 7.2 mm, abdomen 6.8 mm). Head (Fig 8 D) with first antenna filiform and length subequal to eye plus peduncle. Second antenna subcylindrical but with a markedly narrower recurred apex; antenna a little longer than eye plus peduncle. Naupliar eye distinct and midway between compound eyes. Labrum with a prominent recurved spine. Thorax (Fig 8 E) without dorsal or lateral tumidities, but thoracic segment 9 with a prominent lateral lamellar lobe extending posteriolaterally to segments 10 and 11. Segments anterior to ninth with small lateral lobes, biggest on segment 8. Lateral and posterior edges of the segment 9 lamellar lateral lobe sclerotized; dorsum of segment 11 also sclerotized and with a minor round protuberance laterally. Brood pouch lying laterally to the genital segments, each with anterior edge sclerotized, rounded and adpressed against the posterior edge of the lateral lamellar lobe of segment 9. Each brood pouch half pyriform and joined ventrally to a gonopore on a short tubular process. Eggs round and smooth-surfaced at low magnifications. Ten thoracopod pairs, with first half the size of the others and the last three a little shorter. Eleventh thoracic segment without appendages. Thoracopods 2–7 similar to those of male though proportions slightly different, most noticeably the broader than long endopodite. First thoracopod (Fig 7 C) of very different proportions than in standard Parartemia thoracopod. Endopodite almost round, exopodite small and oval shaped, epipodite oval shaped and praeepipodite sausage shaped. Endopodite and exopodite with fewer posterior setae than usual, namely about 14 and 20 respectively. Endites 1 + 2 and 3 of normal relative size and setation, but endites 4 to 6 very different; all three lack posterior setae and 4 and 5 bear elongated bent anterior setae with apical twofifths with a double pectin. Thoracopod 10 (Fig 7 D) is different again, lacking the epipodite and praeepipodite and with a reduced rounded endopodite (posterior setae reduced to 2 on medial surface and ca. 12 on terminal and lateral edges), but exopodite more typical (and with ca 24 posterior setae). Endites 1 + 2 and 3 bear typical anterior setae, but few posterior setae (ca. 12 and 3 respectively). Endites 4 to 6 without posterior setae and anterior setae reduced to one each with those of endite 4 and 5 longer than usual. Abdominal segments papillate, otherwise proportions as in males. Variability. Body lengths in the study material vary up to 20.4 mm in males and 14.2 mm in females. Fusion of the basal antennomeres is sometimes not at right angles to body axis, but as low as 75 o. The distinctive frontal processes are only fully developed in mature males. The fold on the medial edge of the ventral processes sometimes has a distinct point mid length and reaching almost to the ventral edge of the process. The ventral conical mound at the base of the lateral edge of the ventral processes is indistinct in many specimens. The main variability on females concerns the area between the lateral edge of segment 9 and the forward extension of the brood pouch: in some specimens there is a hook-like structure pointing forward or at least a small outgrowth laterally. In a few specimens the dorsal integument of segment 11 is only weakly sclerotized. The second antennae do not always terminate in a thin curved point, but may be more mamilliform. Differential diagnosis. Male P. bicorna sp. nov. is most similar to males of P. serventyi and to a lesser extent to males of P. informis. Distal antennomeres in both P. b i c o r n a sp. nov. and P. serventyi are identical, both with a characteristic mesial tumidity. Anterior, ventral and medial processes are almost identical in the two species, but there are three minor differences: (a) the anterior processes in mature P. b i c o r n a sp. nov. are more robust, being 1.25: 1 longer than wide, whereas in P. serventyi the ratio is closer to 1.5: 1, (b) the fold on the medial edge of the ventral processes is more pronounced in P. bicorna sp. nov., and (c) the ventral conical mounds on the base of the lateral margin of the ventral processes, if present, are small compared with those in P. serventyi which are larger and separate from the ventral processes. There is a more obvious difference between the two species in the lateral lobes of the thorax and genital segments―those of P. b i c o r n a sp. nov. show a gentle gradient in size with lobes of the 11 th thoracic segment just the greatest, whereas in P. serventyi, the lobe on the 11 th thoracic segment is at least twice the size of that of the 10 th segment or first genital segment. The difference between P. b i c o r n a sp. nov. and P. informis is more pronounced. The anterior processes are much shorter in P. informis than in P. bicorna sp. nov., and the ventral processes lack a medial fold in P. informis compared to a fold being present in P. b i c o r n a sp. nov. Two minor differences are in the lateral corner of the frontal processes which is rounded in P. b i c o r n a sp. nov. but square in P. informis and in the number of spines in the basal coronet of the endopodal setae: 20 in P. informis. Also there are more anterior setae on the endites 1 to 3, the endopod and the exopod in P. informis, but this could be because P. informis is generally larger (often> 30 mm) than P. b i c o r n a sp. nov. (usually <20mm). Males of P. bicorna sp. nov. also resemble the males of P. contracta to some degree in that the anterior and ventral processes are broadly similar. However the anterior processes are usually thin and bent in P. contracta compared to being stout and triangular in P. bicorna sp. nov. and the ventral processes lack a medial fold in P. contracta. Another difference is the lack of a mesial tumidity in the distal antennomeres of P. contracta. Among females there can be no confusion between P. b i c o r n a sp. nov. and P. serventyi. The later has a marked medial bulge on the dorsal surface of the 8 th thoracic segment and no lateral plate on segment 9, whereas P. b i c o r n a sp. nov. has no bulges on segment 8 and has a lateral plate on segment 9. Likewise P. contracta is different in that the lateral lobe of segment 9 terminates in a point posteriolaterally and does not envelop segments 10 and 11, whereas in P. b i c o r n a sp. nov. the lateral lobe of segment 9 envelops segments 10 and 11 and terminates in a rounded posterior edge. Female P. bicorna sp. nov. are most similar to female P. informis. Both have a lateral lamellar lobe on segment 9 enveloping segments 10 and 11 and both have laterally bulging brood chambers. There are two lateral papillae on the dorsum in the enclosure, but on thoracomere 10 in P. informis and thoracomere 11 in P. bicorna sp. nov. The lateral extension of thoracomere 9 is wider than long in P. b i c o r n a sp. nov. and narrower than wide in P. informis. Should the specimens be appropriately preserved there is a moderate budge medially on segment 9 in P. informis, but not in P. bicorna sp. nov. Distribution and ecology. To date, P. bicorna sp. nov. has been found only in Lake Carey, near Laverton in the northern goldfields of Western Australia (Timms, et al., 2006, 2009) (Fig. 4). It occurs only in the main lake and sometimes shares this with Parartemia laticaudata sp. nov., an inhabitant of salinas around the lake and pools in inflowing creeks and elsewhere in northern Western Australia (Timms et al., 2006, 2009), and also with Branchinella simplex (Timms et al., 2006). Field salinity range is 22–105 g /L and it occurs in any season after rain fills part or all of the lake (Timms et al., 2006; B. Datson, pers. comm.). Given it is restricted to just Lake Carey, Timms et al. (2009) suggest it should be given Priority One status under the Western Australian Department of Conservation’s priority species listing process.Published as part of Timms, Brian V, 2010, Six new species of the brine shrimp Parartemia Sayce 1903 (Crustacea: Anostraca: Artemiina) in Western Australia, pp. 1-35 in Zootaxa 2715 on pages 14-17, DOI: 10.5281/zenodo.19970
Branchinella herrodi Timms, 2012, sp. nov.
No full textBranchinella herrodi sp. nov. Figs. 1 G, 8, 9A. Etymology. This species is named for the Herrod family longtime proprietors of Yarromere Station, via Pentland, North Queensland, in particular patriarch Kevin Herrod for his assistance and concern for my well being as I collected shrimp in remote parts of the property. Type locality. Queensland, Lake Buchanan northwest beaches, pool 1.3 km sw of Lake Constant southern shore, 21 o 34 ’ 31 ”S, 145 o 47 ’ 32 ”E, 24 February, 2008, BVT Holotype Male deposited in Australian Museum. Total length 9.5 mm. Accession number: AM P 88354. Allotype Female deposited in Australian Museum. Total length 11.2 mm. Accession number: AM P 88353. Paratypes. Queensland, Lake Buchanan northwest beaches, pool 1.3 km NE of Lake Constant northern shore, 21 o 32 ’ 38 ”S, 145 o 48 ’ 29 ”E, 26 February, 2008, BVT, AM P88355, 4 males, 3 females. Other Material. Queensland, Lake Buchanan northwest beaches, pool 1.3 km w of Lake Buchanan northwest shore, 21 o 32 ’ 00”S, 145 o 48 ’ 13 ”E, 26 February, 2008, BVT, AM P88356, 5 males, 3 females. Diagnosis. Frontal appendage branched, each branch with ca 10 lateral subbranches and 5 lateral medial branches plus a larger one basomedially. Branches terminate in a mixture of small spines and epidermal outgrowths. Male fifth thoracopods distinct with various anterior setae and endopod lack basal knob-like extensions (as in B. wellardi) but with 6–8 spinules on their base. Females unremarkable. Description. Male. Eyes freely projecting on peduncles about the same length as eye diameter. First antennae filiform, slightly longer than second antenna proximal antennomere, and terminating in 3–5 long sensory setae. Second antennae with proximal antennomere subequal in length to distal antennomere. Proximal antennomeres well separated on each side, being fused basally at 90 o and medially with a long shallow swelling covered in very small denticles. Distal antennomeres of uniform diameter and with transverse ridges medially. Frontal appendage larger than the second antennae, consisting of short trunk and two ramified branches almost three times trunk length. Each branch with 9–10 subbranches laterally and 4–5 medially, but with one larger branch of different structure basomedially. These subbranches about the same size medially and laterally and decreasing in length towards the branch apex. Each branch terminating in a short spine apically attended by 2–4 smaller spines subapically. Narrow conical outgrowths randomly distributed ventrally along each branch, mainly posteriorly to the larger medial subbranch. Similar outgrowths but smaller along the subbranch generally in pairs. Largest medial branches smooth, each consisting of a short thick trunk and an oval plate at about 60 o to the trunk, so overall the axis of the plate and branch trunk similar. Fifth thoracopod with endite 1 + 2 and 3 evenly curved, the former about three times the size of the later. Anterior setae of endite 1 smooth, and about half the length of adjacent posterior setae. Anterior setae of endite 2 about half the length of anterior seta and bearing a strong pecten of spines and attended at its base by a small smooth spine. Endite 3 with an anterior setae similar on length to the first anterior seta, and bearing a strong pecten of spines and attended at its base by a short smooth spine. Endites 4–6 asymmetrical and covered with small spines. Endites 4 and 5 with two anterior setae and endite 6 with one anterior seta, representing two types. The first on all three endites with a fine pecten most of their length and a few spines basally; the seta on endites 6 a little longer than the other two. The second seta type on endites 4 and 5 only, comparatively short (half length of adjacent anterior seta) and naked. Posterior setae of all endites long and numbering about 60 on endites 1 + 2, near 18 endite 3, then 3,2, 2 respectively on endites 4–6. Endopod squarish with a shallow wide notch apically. It bears 10 spaced feathered setae medially to the notch and 18 closer together apically and laterally. Setae larger on the apex than proximal sides. The ca 40 feathered setae on the exopod each about 50 % longer than endopod setae. Basal attachment of endopod setae with 6–8 spinules compared with 3–4 on the exopod setae base. Epipod broadly oval and naked. Praeepipodite large (about equivalent to exopod + endopod) and with smooth edges. Genital segments about same width as nearby thoracic and abdominal segments. Bases of gonopods about half the length of the first abdominal segment. No specimens with gonopod everted. Cercopods typical for Branchinella. Female. Eye plus peduncle on each side about head width. First antenna filiform, almost as eye plus peduncle. Second antenna with a wide base and narrowing to an asymmetrical sharp apex and longer than the labrum. Genital segments subequal to posterior thoracic and adjacent abdominal segments. No tumidities. Brood pouch expanded ventrally and tubular posteriorly and terminating at about the second abdominal segment. Fifth thoracopod and cercopods as in male. Egg diameter 175 µm. Depressions average number 35 and irregularly polygonal to constricted and linear, inter-depression walls wide and ridge crests rounded and with minute pores (Timms and Lindsay, 2011). Variability. There is some variability in the number of subbranches of the frontal appendage, but only one either way from the number in the holotype. The larger basomedial branch can be of various sizes, perhaps associated with the developmental stage of the specimen. As indicated for this holotype the placement of the narrow epidermal outgrowths is quite variable in other frontal appendages examined, but always they are ventral and lateral and most common in the apical half of each subbranch. Differential diagnosis. Branchinella herrodi sp. nov. is most similar to B. multidigitata Timms 2008, B. campbelli Timms 2001 and B. wellardi. Branchinella multidigitata has frontal appendage branches with subbranches reminiscent of those in B. herrodi sp. nov., but with 6 laterals, 3 terminals, 3–5 very small medials and no larger basomedial in B. multidigitata compared to 9–10 laterals, 0 terminals, 4–5 fully developed medials and a large basomedial subbranch in B. herrodi sp.nov. The basomedial subbranch in B. herrodi sp.nov. is similar to that in B. campbelli, but that is the only feature of resemblance. Given that there is <4 % variation in 16 SmtDNA (Pinceel et al., 2012) between B. herrodi sp.nov. and B. wellardi, this is the species it is most likely similar too, or indeed conspecific. While their frontal appendages are superficially similar, there are many morphological differences between the two: (a) B. wellardi has a bilobed lamellar outgrowth between the two branches, B. herrodi sp.nov. does not (Figs. 8 A, 12 A); (b) B. wellardi has 9–10 pairs of lateral and medial subbranches to the branches, whereas B. herrodi sp.nov. has 9–10 laterals and 4–5 medials (Figs. 8 B, 12 B); (c) the branches of B. wellardi are usually pseudosegmented but not in B. herrodi sp.nov. (Figs. 8 B, 12 B); (d) the subbranches have paired thickenings each terminating in a chitinous epidermal outgrowth in B. wellardi, while in B. herrodi sp.nov. the branches are of more uniform thickness, terminate in a spine attended subapically by 2–4 smaller spines and the epidermal outgrowths are scattered (Figs. 8 B, 12 B); and (e) only B. herrodi sp.nov. has a larger basomedial branch (Fig. 8 B). The second antennae of both species are very similar, though that in B. herrodi sp.nov. has a shallow tumidity covered in minute denticles medioapically, whereas the medial surface in B. wellardi lacks denticles and spinules (Figs. 8 A, 12 A). The thoracopods are also very similar, as they are in many of the smaller species of Branchinella, but four medial endopod setae are inserted on knob-like protrusions in B. wellardi compared to 6–7 medial setae inserted normally in B. herrodi sp.nov. Their bases have 6–8 spinules whereas those in B. wellardi are smooth (Figs. 9 A, B). Resting eggs of B. herrodi sp.nov. are like the undistinctive eggs of B. affinis, B. anatinorhyncha sp. nov., etc, whereas eggs of B. wellardi have markedly concave and regular polygonal depressions (Figs. 1 G, J). Thus the conclusion is inescapable that despite the being similar molecularly (in the 16 Smt segment), B. herrodi sp.nov. is distinct from B. wellardi. Distribution and Ecology. B. herrodi sp.nov. is common in many of the clear freshwater pools in old swales between the fossil high beaches of Lake Buchanan. They have not been found in hyposaline/mesosaline pools associated with Lake Buchanan and its inflowing streams, nor in the saline lake itself (the domain of Parartemia minuta Geddes 1973 and Branchinella buchananensis Geddes 1981) (Timms, 1987), nor in claypans in the greater region. Most of the pools only contain water after heavy summer rains.Published as part of Timms, Brian V, 2012, Further studies on the fairy shrimp genus Branchinella (Crustacea: Anostraca: Thamnocephalidae) in Australia, with descriptions of five new species, pp. 35-60 in Zootaxa 3595 on pages 49-52, DOI: 10.5281/zenodo.25459
Parartemia purpurea Timms, 2010, sp. nov.
No full textParartemia purpurea sp. nov. (Figs 4,7,11) Parartemia n sp a Timms and Savage, 2004, p 22, 28; Timms 2009. Etymology. This species is named for the distinct purple colouration of mature females, the name being derived from the Latin purpurea meaning purple. Holotype. One male, 44 km NNE of Esperance, unnamed lake on Dempster Rd, (33 o 28 ’ 58 ”S, 122 o 00’ 38 ”E), 8 October 2008; BVT, WAM 45235. Allotype. One female, same collecting data as holotype, WAM 45236. Paratypes. Two males, two females, some collecting data as holotype, WAM 45237; two males, two females, same collecting data as holotype, AM 82976. Other material. 10 males, 10 females, 23.5 km E of Scaddan, unnamed lake on East Lignite Rd, (33 o 19 ’ 28 ”S, 121 o 58 ’ 17 ”E), 2 August 2005, BVT, WAM 45238; 10 females, 38 km N of Esperance, unnamed lake on south side of Speddingup Rd, (33 o 31 ’ 01”S, 121 o 52 ’ 21 ”E), 8 October 2008, BVT, WAM 45239; 10 males, 10 females, all immature, 64.5 km NE of Esperance near Kau Rock, unnamed pond, (33 o 24 ’ 32 ”S, 122 o 20 ’ 00”E), 9 October 2008, BVT, WAM 45240; 10 males, 10 females, 80 km NE of Esperance in Beaumont Nature Reserve, unnamed lake, (33 o 27 ’ 37 ”S, 122 o 36 ’ 43 ”E), 5 September 2004, BVT, WAM 45241. Description. Male. Length 21.5 mm (head plus thorax 7 mm, abdomen 14.5 mm) First antenna (Fig. 11 A) filiform, a little longer than eye plus peduncle. Second antenna. Basal antennomeres (Fig. 11 A) fused at about 75 o to body axis. Ventral margin with paired ventral processes (Fig. 11 A) about 3 times longer than deep, with distoventral corner rounded but not protruding and medioventral corner sharp, almost a right angle. Ventral process margin with well spaced minute spines, also a few such spines on dorsal surface of the processes. Medial margin of ventral processes about 1.2 times longer than lateral margin. Medial space between ventral processes narrow with parallel margins and terminating basally in a short notch. Ventrolaterally just lateral to basodistal margin of the ventral process a raised circular area, the conical mound, with numerous minute spines. Anterior processes (Fig. 11 A) small, blunt triangular, about one quarter depth of ventral processes. Distal antennomere (Fig. 11 A) almost twice as long as basal antennomere, curved medially, cylindrical and tapering to a sharp apex. Labrum lacking a spine. Thoracomeres (Fig 10 B) enveloped laterally in small fused lobes to form a narrow lateral flange along whole length of thorax. Thorax widest at thoracomeres 10 to 11, with lobe on first genital as wide as lobe on T 11 anteriorly, but markedly narrowing posteriorly. No lobe on second genital segment. Eleven pairs of thoracopods, with first two reduced in size and last without an epipodite. Fifth thoracopod typical for the genus. Gonopods (Fig. 11 C) fused basally. Each apical free portion with a short hooked digitiform process inserted ventrolaterally at about three quarters the length of the free portion. No basal spine. A paratype with gonopod everted (Fig. 11 D)— everted part a little longer than free basal portion, consisting of a basal wide cylindrical component and a tubular distal part of two diameters, a middle section narrower than basal tube and an apical, very narrow apical section. Whole expanded section naked except for a two recurved spines on a single base posteriolaterally on the wide cylindrical component. Abdomen long, 2.1 times head plus thorax. Segments increasing in length and but hardy decreasing in diameter sequentially 1 to 6, with sixth 2.2 times the length and but only marginally narrower than first segment. Telson inflated and not clearly demarked from sixth abdominal segment and cercopods about length of fourth abdominal segment and clothed with setae medially and laterally. Female. 11 mm (head plus thorax 6.7 mm, abdomen 4.3 mm). In life, mature females coloured a deep purple, with the brood chambers a lesser intense colour. Head (Fig. 11 E) with first antenna filiform and slightly shorter than length of eye plus peduncle. Second antenna a little longer than twice eye plus peduncle length, somewhat flattened, and narrowing evenly to a sharp apex. Labrum with a prominent recurved spine. Thoracomeres (Fig. 11 F,G) 1 – 6 and 8 normal, thoracomere 7 with a lateral tumidity, thoracomeres 9 and 10 each with a dorsolateral lamella, with a sclerotized and denticulate margin. Dorsolateral lamella of thoracomere 9 asymmetrical, narrow dorsally and widest ventrolaterally and with subsidiary ventrolateral lamella, while lamella of segment 10 more symmetrical and more ventrolateral. Thoracomere 11 somewhat reduced. Eleven pairs of thoracopods, 2 nd and 10 th pairs a little shorter than most, 1 st about half size and 11 th reduced to just a pair of stubs bearing a few spines. First thoracopod (Fig. 7 J) with all normal components, but endopod and particularly exopod reduced, so that both have fewer posterior seate than normal and exopod just protruding beyond endopod. Normal anterior setae, and with basal anterior setae of endite 4 enlarged, longer than adjacent posterior setae. Fifth thoracopod of normal construction for Parartemia and similar to that in males. Tenth thoracopod (Fig. 7 K) with most structures reduced, particularly endites 1 + 2 and 3, endopod and praeepipodite, and with epipodite lacking. Exopodite of normal relative size and projecting well beyond the endopodite. Anterior setae of endites all present, but reduced in size. Eleventh thoracopod (Fig. 7 L) a stub with terminally what appears to be a very reduced endopod with five setae, and medially two protuberances, the distal one with two setae and a basal greater naked protuberance. These protuberances could be endites. Brood pouch (Fig. 11 F,G) lateral lobes oval structures in dorsal view but more quadrahedral laterally, and connected ventrally, with a posteriorly directed gonopore, borne on a tubular projection. Abdomen segments typical for Parartemia, i.e. segments increase in length and decrease in diameter sequentially from segments 1 to 6. Surface denticulate. Variability. Mature males vary in length from 16 to 23 mm. The basal antennomeres are fused at various angles, probably influenced by preservation, of 60–80 o to body axis and while the frontal processes seem always to be small, blunt and triangular, the ventral processes vary so that the distoventral corner may protrude a little and the medial space varies from being almost closed to being open by a distance up to about one third the depth of the ventral processes. The medial margins of the ventral processes may not always be parallel, but occasionally are V-shaped or uneven. However, the angle of near 90 o on the medioventral corner of the ventral processes varies little. The raised spinose area ventrolaterally to the basodistal margin of the ventral processes may be expressed as a conical mound or may be hardly present. The flange on the thoracic margins is generally present, but its widest part may be at thoracomere 10 or occasionally 11, i.e. more posterior than at thoracomere 8–9. Abdomen length varies from 1.25 to 2.33 times head plus thorax length (average of 1.78 in 10 specimens). This length is due in part to the relatively long 6 th segment which on average is 2.1 times length of 1 st segment. The first ratio is greater than for P. longicaudata and the second only a little less than in P. longicaudata, the species supposedly with an extraordinary long abdomen (see earlier). Mature females range in length from 9.6 to 11.2 mm, and while opaque white in preservation, in life are almost always a deep purple. The lateral tumidities on thoracomere 7 while usually prominent, are sometimes deflated and not noticeable. The lateral lamellae of thoracomere 9 and 10 vary in development, but the lamella of thoracomere 9 is always larger than that of thoracomere 10 and more dorsal in position. Differential diagnosis. P. purpurea sp. nov. males are most similar to P. zietziana due to their broadly similar ventral processes and the shape of the medial area between these processes. However P. zietziana has digitiform anterior processes compared to short conical processes in P. purpurea sp. nov. The lateral and medial margins of the ventral processes are of similar length in P. zietziana, but the medial margin is about 1.2 times longer than lateral margin in P. purpurea sp. nov. The ventrolateral area at the basodistal margin of the ventral processes is different in the two species: in P. purpurea sp. nov. it is raised and very spinous, but in P. zietziana it hardly present, if at all. Finally the abdomen is relatively longer in most specimens of P. p u r p u re a sp. nov. (1.78 times) than in P. zietziana (1.30 in 10 specimens). The two species have different distributions separated by the Nullarbor Plain – P. zietziana occurs in central lowland Tasmania, southern Victoria, and southern South Australia to as far west as the eastern Eyre Peninsula, while P.purpurea sp. nov. occurs in the Esperance hinterland area of Western Australia (Timms et al., 2009). Females are distinct from all other species due to the lack of dorsal swellings and horizontal lateral lobes on various thoracic segments, and the presence of lateral swellings on thoracomere 7 and vertical lateral flaps on thoracomere 9 and 10. Furthermore it is unusual in Parartemia females to have a vestige of thoracopod 11 as P. p u r p u re a sp. nov. does; closest species in this character is P. acidiphila with 3 terminal setae, P. laticaudata sp. nov. with two terminal spines and P. longicaudata with a subterminal spine. Distribution and ecology. P. purpurea sp. nov. occurs in alkaline saline lakes in the Esperance hinterland, from about Grass Patch-Scadden eastwards for about 90 km to Beaumont Nature Reserve (Timms et al., 2009)(Fig. 4). It occurs over a salinity range of 20 to 235 g /L and in lakes with pH varying from 6.9 to 10.4 (Timms, 2009 b; Timms et al., 2009). Generally it occurs in late winter- spring as lakes fill with winterspring rains, reproduces in September and October with purple coloured females actively swimming in the shallows and depositing eggs. Occasionally summer rains fill the lakes, in which case P. purpurea sp. nov. responds as it does to a winter filling (Timms, 2009 b). Females are easily predated upon by waders (mainly Stilts, Avocets) as they swim conspicuously in shallow waters, so that sex ratios can become very biased towards males which tend to stay in deeper waters (author, unpublished observations). Presently it is common throughout this area as few lakes are salinised.Published as part of Timms, Brian V, 2010, Six new species of the brine shrimp Parartemia Sayce 1903 (Crustacea: Anostraca: Artemiina) in Western Australia, pp. 1-35 in Zootaxa 2715 on pages 24-27, DOI: 10.5281/zenodo.19970
Parartemia boomeranga Timms, 2010, sp.nov.
No full textParartemia boomeranga sp.nov. (Figs. 4,6,7) Parartemia n sp c Timms & Savage, 2004, p 22, 26, 35. Etymology. The specific name is suggested by the boomerang-shaped thick area (short arms at an angle and thickened mid region) on the medial surface of the ventral processes. These fit snugly against the female 11 th thoracopod semispherical bases in amplexus. Holotype. One male, unnamed lake on Gunyidi - Wubin Road, 15.5 km E of Gunyidi, (30 o 07’ 08”S, 116 o 14 ’ 36 ”E), 14 September 2003, BVT, WAM 45211. Allotype. One female, same collecting data as holotype, WAM 45212. Paratypes. Two males, two females, some collecting data as holotype, WAM 45213; two males, two females, same collecting data as holotype, AM P 82972. Description. Male. Length 22.2 mm (head plus thorax 9.1 mm, abdomen 13.1 mm). First antenna (Fig 6 A) filiform, about 1.5 times length of eye plus peduncle. Second antenna. Basal antennomeres (Fig 6 A) fused at an angle of about 45 o from body axis. Ventral margin with paired ventral processes (Fig 6 A) about 2.5 times longer than deep. Distoventral corner of ventral processes broadly rounded and slightly protruding, ventral margin weakly concave and medial margin curved asymmetrically with maximum protrusion about two thirds distance from ventral margin and inner margin well indented into the ventral process, so that whole medial portion of the ventral process unsupported from the ventral margin of the basal antennomere. However this portion with a boomerang-shaped thickened area. Lateral and ventral margins of ventral process clothed with well spaced small spines. Medial area between ventral processes concave. Anterior processes (Fig 6 A) digitiform, small and length about equal to depth of ventral processes. Distal antennomere (Fig 6 A) about twice length of basal antennomere, generally curved medially and tapering to a sharp apex, but apical portion convexly curved and with a tumidity mesially. Thoracic segments with small lateral lobes, increasing in size posteriorly and reaching a maximum on segment 11. Lateral bulge on first genital segment even greater than 11 th lobe, so that maximum body width in genital segments. Eleven pairs of thoracopods, with first two reduced in size and last without an epipodite. Gonopods (Fig 6 B) fused basally. Each free apical portion with a basal sharp spine and a ventrolateral short digitiform process at about two-thirds the length of the appendage. Abdomen with segments increasing in length and decreasing in diameter sequentially 1 to 6, with sixth 1.75 times length and half the diameter of first segment. Female. Length 15.3 mm (head plus thorax 9 mm, abdomen 6.3 mm). Head (Fig 6 C) with first antenna filiform, a little shorter than eye plus peduncle. Second antenna somewhat longer than length of eye plus peduncle, flattened, with parallel sides and a round symmetrical apex bearing a short narrow and pointed appendix. Distinct naupliar eye midway between bases of first antenna. Labrum with a recurved spine. Thoracic segments (Figs. 6 D,E) 1–7 normal, segment 8 with a trapezoid dorsum and small lateral lobes, segment 9 with a prominent dorsal swelling and larger lateral lobes, segment 10 reduced with a narrow dorsum and apparently no lateral lobes and segment 11 with a less reduced dorsum and large lobes extended posteriolaterally into a triangular extension and ventrally into a rounded swelling. Dorsal surfaces of segments 10 and 11 sclerotized. Most thoracopods as in male. First thoracopod (Fig 7 A) reduced in size but hardly in relative size of component parts. Both basal anterior basal setae of endites 4 and 5 elongated. Tenth thoracopod (Fig 7 B) also reduced in size and in relative size of components. Endites 1 + 2 and 3 small and with few posterior setae, exopodite semi-oval, basal anterior seta of endite 4 long, but other anterior setae of normal relative lengths. No 11 th thoracopod, but distinct base in the form of a semispherical mound. Anterior edge of first genital segment (Figs. 6 D,E) a collar with a lateral protrusion reaching anteriorly over lobe of 11 th thoracic segment. Brood pouch (Figs. 6 D,E) wider than long, so that whole structure approaches three times width: length. Anteriolateral and posteriolateral corners prominent and a shallow groove between them. Lobes joined ventrally into a short tubular structure, directected posteriorly bearing the gonopore. FIGURE 7. Female thoracopods. A, P. boomeranga sp. nov. 1 st thoracopod; B, P. boomeranga sp. nov. 10 th thoracopod; C, P. b i c o r n a sp. nov. 1 st thoracopod, length; D, P. b i c o r n a n. sp 10 th thoracopod; E, P. laticaudata sp. nov. 1 st thoracopod; F, P. laticaudata sp. nov. 10 th thoracopod; G, P. laticaudata sp. nov. 11 th thoracopod; H, P. mouritzi sp. nov. 1 st thoracopod; I, P. mouritzi sp. nov. 10 th thoracopod; J, P. purpurea sp. nov. 1 st thoracopod; K, P. purpurea sp. nov. 10 th thoracopod; L. P. purpurea sp. nov. 11 th thoracopod; M, P. ve ro n ic a e sp. nov. 1 st thoracopod; N, P. veronicae sp. nov., 10 th thoracopod. For further explanation on the thoracopods see legend of Fig. 3. Differential diagnosis. This species is most similar to P. longicaudata, and indeed in an early key (Timms, 2004), males of the two species were inseparable. However, there are a number of minor differences: (a) the ventral processes are proportionally longer in P. boomeranga sp. nov., (b) the medial edge of the ventral processes is much more convex (boomerang shaped) in P. boomeranga sp. nov. than in P. longicaudata, (c) the medial thickened area in the ventral processes in P. longicaudata is almost straight, while in P. boomeranga sp. nov. it is boomerang shaped, (d) the distal antennomere is evenly concavely curved in P. longicaudata, but in P. boomeranga sp. nov. it is unevenly curved because it is thickened midlength and has outwardly curved apices, (e) the sixth abdominal segment is> twice the length of the first in P. longicaudata, but <twice in P. boomeranga sp. nov., (f) the basal spine of the gonopod is curved in P. longicaudata but straight in P. boomeranga sp. nov. and (g) the distal spine is sited about half way along the gonopod in B. longicaudata but two-thirds the distance in P. boomeranga sp. nov. While females of the two species (P. longicaudata, P. boomeranga sp. nov.) share some important characteristics, e.g. the segment 9 large dorsal tumidity and its large lateral lobes, segments 10 and 11 are dorsally sclerotized in both, and there are large ventrolateral tumidities on segment 11 in both. However there are many differences: (a) the first antenna are longer than the eye plus peduncle, and the narrow apical portion of the second antenna is longer than antenna width in P. longicaudata, as opposed to the first antenna being shorter than the eye plus peduncle, and narrow apical portion of second antenna being shorter than its width in P. boomeranga sp. nov., (b) thoracic segment 8 lacks a lateral lobe in P. longicaudata, but has one in P. boomeranga sp. nov., (c) segment 10 is larger than segment 11 in P. longicaudata, but relative size is reversed on P. boomeranga sp. nov., (d) in P. boomeranga sp. nov. segment 11 has large lateral lobes extended posteriorly in triangular projections, and (e) the brood pouch is generally trapezoid in P. longicaudata, but rectangular in P. boomeranga sp. nov. Distribution and ecology. P. boomeranga sp. nov. is known from only a few lakes in a narrow band northeast of Perth from near Gunyidi to Wubin to Kalannie to Cunderin (Timms et al., 2009)(Fig. 4). Most of its known sites are salinised and extant populations have not been located 2006–2008, leading Timms et al. 2009) to suggest this species be listed as Vulnerable under ICUN criteria. Little is known of its ecological requirements, other than a maximum salinity record of 120 g /L (Timms et al. 2009).Published as part of Timms, Brian V, 2010, Six new species of the brine shrimp Parartemia Sayce 1903 (Crustacea: Anostraca: Artemiina) in Western Australia, pp. 1-35 in Zootaxa 2715 on pages 11-14, DOI: 10.5281/zenodo.19970
Branchinella hearnii Timms, 2012, sp. nov.
No full textBranchinella hearnii sp. nov. Figs. 1 F, 5 B, 7. Etymology. This species is named for Roger Hearn of Manjimup, who first collected this species from Little Unicup Lake, near Lake Muir in southwest Western Australia in 2005 and then displayed beautiful live specimens to the staff and myself as a visiting scientist at the Department of Environment and Conservation’s aquatic laboratory at Wanneroo. Type locality. Western Australia, ca. 12 km N of Lake Muir, Little Unicup Lake, 34 o 19 ’ 46.9 ”S, 116 o 42 ’ 51.8 ”E, 19 August 2009, BVT Holotype. Male deposited in the Western Australian Museum. Total length: 28 mm Accession number: WAM C 49896. Allotype. Female. Total length: 28 mm. Accession number: WAM C 49897. Paratypes. 1 male, 5 females same data, WAM C 49898; 2 male, 7 females, Western Australia, ca. 10 km N of Lake Muir and 1 km S of Unicup Lake, ‘Branchinella’ Lake, 34 o 21 ’ 41 ”S, 116 o 43 ’ 22 ”E, 6 October 2008, BVT, WAM C 49899. Other Material. Numerous juveniles, Western Australia, ca. 12 km N of Lake Muir, Little Unicup Lake, 34 o 19 ’ 46.9 ”S, 116 o 42 ’ 51.8 ”E, 5 September 2007, R. Hearn, WAM C 49900; 1 male 9 females, Western Australia, ca. 14 km N of Lake Muir, Tolkerup West Lake, 34 o 19 ’ 59.4 ”S, 116 o 43 ’ 21.1 ”E, 6 September 2007, R. Hearn, WAM C 49901; 1 male, 1 female, Western Australia, ca. 10 km N of Lake Muir and 1 km S of Unicup Lake, ‘Branchinella’ Lake, 34 o 21 ’ 41 ”S, 116 o 43 ’ 22 ”E, 2 November 2007, R. Hearn, WAM C 49902; 12 juveniles, Western Australia, ca 18 km N of Lake Muir, ‘Cricket Ground Lake,’ 34 o 16 ’ 17.5 ”S, 116 o 42 ’ 03.8”E, 4 September 2008, R. Hearn, WAM C 49903; 2 males, 4 females, Western Australia, ca. 14 km N of Lake Muir, Tolkerup West Lake, 34 o 19 ’ 59.4 ”S, 116 o 43 ’ 21.1 ”E, 6 October 1908, BVT, WAM C 49904; many juveniles, 2.4 km SW of Watheroo, ‘Bentonite Lake,’ 30 o 18 ’ 46 ” S, 116 o 02’ 33 ”E, 5 September 2009, BVT, WAM C 49905; 6 males, 2 females, 4.7 km W of Coomberdale, 30 o 28 ’ 02”S, 115 o 59 ’ 18 ”E, 6 September, 2009, BVT, WAM C 49906. Diagnosis. Frontal appendage short and forked and not reaching beyond the bases of the second antennae. Second antenna medial surface of proximal antennomere with large plate like tumidity on each side. Each gonopod flanked by a lateral swelling with a central hollow. Females with a lateral tumidity on each genital segment and paired dorsal tumidities on the first genital segment. Anterior setae of fifth thoracopod with endites 4 and 5 anterior setae naked and more than twice as long as second anterior setae on endites 4–6 which carry a pecten of fine spines. Description. Male. Eyes freely projecting on peduncles about the same length as eye diameter. First antennae filiform, a little longer than second antenna proximal antennomere, and terminating in 3–5 long sensory setae. Second antennae. Proximal antennomere slightly shorter than distal antennomere. Proximal antennomeres usually well separated from each other and fused basally at about 45 o. Each proximal antennomere with a large lamellar projection aligned ventrally. This projection, lacking sensory denticles or spinules, supported posteriorly by a ventrally narrowing ridge. Distal antennomeres of uniform diameter, gently arcing medially, and with weakly developed transverse medial ridges. Frontal appendage small, bifurcated, not protruding beyond the fused basal antennomeres. Fifth thoracopod with endite 1 + 2 and 3 evenly curved, the former about three times the size of the later. Anterior setae of endite 1 naked, of similar length to adjacent posterior setae. Anterior setae of endite 2 a little shorter than first anterior setae, bearing a pecten of spines and attended at its base by a small smooth spine. Endite 3 with an anterior setae longest of the three anterior setae on endites 1 to 3, about 7 / 8 th the length of the adjacent posterior setae, and bearing a pecten of spines. This anterior setae also attended by a small spine at its base. Endites 4–6 asymmetrical and covered with small spines. Endites 4 and 5 with two anterior setae and endite 6 with one anterior seta, representing two types. The first of all three endites, about 1 / 3 rd the length of the adjacent anterior setae and with a fine pecten most of their length. The second type on endites 4 and 5 only, 3 / 4 the length of adjacent posterior setae and naked. Posterior setae of all endites long and numbering about 27 on endites 1 + 2, about 9 on endite 3, then 4, 3, 4 respectively on endites 4–6. Those on endites 1 + 2 increasing in length basally to apex. Endopod broadly triangular shaped but with two closely spaced apices; straightest medial surface bearing about 12 spaced setae and curved lateral surface bearing numerous (ca 70) closely spaced setae. Exopod unevenly oval (medial edge more rounded than lateral edge) bearing about 90 closely spaced posterior setae. Setal bases with 3–6 minute spines. Epipodite elongate oval and unadorned. Praeepipodite large and broad, larger than endopod and exopod combined, and with a finely serrated margin. Genital segments about same width as adjacent thoracic and abdominal segments. Bases of gonopods a little longer than one abdominal segment each flanked by a lateral swelling with a central hollow. Everted gonopod with a long row of about 15 triangular spines medially and a wide field of longer thin spines on opposite side. Cercopods typical for Branchinella. Female. Eye plus peduncle about half the width of the head. First antenna filiform, a little longer than eye plus peduncle. Second antenna lamellar, about three times the head width on each side and narrowing to a sharp symmetrical apex. Second antennae fused together medially. Genital segments larger than adjacent thoracic and abdominal segments and with distinctive swellings and projections First genital segment with a large bulbous lateral tumidity each side and two adjacent asymmetrical pyramid shaped projections dorsally. Apices of these projections produced posteriorly and laterally. Second genital segment with another lateral tumidity on each side but it is sac-like and directed dorsally. Brood pouch bulbous anteriorly with a marked ventral swelling, but tubular posteriorly and terminating at about the third abdominal segment. Fifth thoracopod and cercopods as in male. Egg diameter 485 µm, with about 13 polygonal depressions, each shallow with sharp ridges and concave floor with dimples (Timms and Lindsay, 2011). Variability. Some variability in features was noticed in the material available. Fusion of the second antennal proximal antennomeres ranges from almost 90 o to about 50 o. In males the two ventral tumidities may be up to 25 % smaller than in the holotype and the triangular spines on the gonopod may number up to 24 (see Figs 2 A, B, Timms, 2008). In females the lateral tumidities on the genital segments may be smaller than in the allotype and the apices of the second antennae asymmetrical (see Figs 2 C, D, Timms, 2008), and there may be two weak ventral hooks pointing posteriorly on the brood chamber. The paired dorsal pyramid-shaped projections are invariable. Size. Mature B. hearnii sp.nov. are relatively large. There are 10 males in collections from the Lake Muir area ranging in size from 24 to 30 mm and averaging 26.7 mm, and 13 females in the same collections ranging in size from 19 to 38 mm and averaging 34.6 mm. Generally it is the smaller (immature?) males and females with the smaller tumidities. Differential diagnosis. Branchinella hearnii sp. nov. is almost identical with B. compacta Linder, with which it was initially confused (Timms, 2008), but its 16 SmtDNA differs by 12.8 % (Pinceel et al., 2012). It is separable from this species by many morphological features, including: (a) in males, the ventral lamellar projection on the second antennal proximal antennomere is much larger in B. hearnii sp.nov. than in B. compacta where it is hardly present at all (Fig 4 A, B); (b) most B. compacta males have small sensory spines lining much of the medial surface of the proximal antennomere, whereas this surface is smooth in B. hearnii sp.nov.; (c) in female, B. compacta lateral tumidities on its genital segments are significantly smaller than the large ones in B. hearnii sp.nov. (Fig. 4 C, D, 7 F, G); (d) The anterior setae on endites 4–6 are different in the two species, in B. compacta there are three longer setae each with pectens of spines and two very short naked setae, whereas in B. hearnii sp.nov. there are two longer naked setae and three shorter setae with pectens (Fig. 5 A, B); (e) in B. compacta the medial endopodal setae are feathered and have 10–14 small spines basally whereas in B. hearnii sp.nov. the medial endopodial setae are short, naked and basally spineless (Fig. 5 A, B); and (f ) B. compacta occurs in southeastern Australia, mainly in western Victoria (Geddes, 1981) but including some lakes on the Monaro, NSW (see above), while B. hearnii n.sp, inhabits sites in southwestern Western Australia, both north and south of Perth. Resting eggs of these two species are easily differentiated: those of B.hearnii sp.nov. have fewer depressions than eggs of B. compacta ( 25) and their walls are sharp compared to rounded in B. compacta (Fig. 1 D, F) (Timms and Lindsay, 2011). Given the genital segment tumidities and projections in females and the ventral lamellar projection in the clasper apparatus of males (reminiscent of males of Parartemia — Timms, 2012), it most likely exhibits lock and key amplexus (sensu Rogers, 2002). The male claspers would appress the genital segments perhaps either anterior or posterior to the dorsal pyramid shaped projections, to form a tight union. While all species of the Australian brine shrimp (Parartemia) use lock and key amplexus (Rogers, 2002; Timms, 2011), B. hearnii sp.nov. is the only second known species in Branchinella to possibly use it, its close relative B. compacta being the other candidate. The advantage to it is not clear in the Unicup area as no other species of Branchinella is known from this area, but in the Coomberdale — Watheroo area, B. hearnii sp.nov. shares its known sites with B. erosa sp. nov. Distribution and Ecology. B. hearnii sp.nov. occurs in a few hyposaline lakes to 8 g /L to the north of Lake Muir in southwestern Western Australia as well as in a few lakes, also hyposaline to 12 g /L, in the Coomberdale — Watheroo area north of Moora, Western Australia. In both areas the lakes in which it is found contain clear waters, turbidities 200 NTU.Published as part of Timms, Brian V, 2012, Further studies on the fairy shrimp genus Branchinella (Crustacea: Anostraca: Thamnocephalidae) in Australia, with descriptions of five new species, pp. 35-60 in Zootaxa 3595 on pages 46-49, DOI: 10.5281/zenodo.25459
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