2,507 research outputs found
Coil-to-globule collapse of active polymers: a Rouse perspective
No full textWe derive an effective Rouse model for tangentially active polymers, characterised by a constant active force tangent to their backbone. In particular, we show that, once extended to account for finite bending rigidity, such active Rouse model captures the reduction in the gyration radius, or coil-to-globule-like transition, that has been observed numerically in the literature for such active filaments. Interestingly, our analysis identifies the proper definition of the Peclet number, that allows to collapse all numerical data onto a master curve
Coil-to-globule collapse of active polymers: a Rouse perspective
No full textWe derive an effective Rouse model for tangentially active polymers, characterized by a constant active force tangent to their backbone. In particular, we show that, once extended to account for finite bending rigidity, such active Rouse model captures the reduction in the gyration radius, or coil-to-globule-like transition, that has been observed numerically in the literature for such active filaments. Interestingly, our analysis identifies the proper definition of the Peclet number, that allows to collapse all numerical data onto a master curve
Semivermilia lylevaili Kupriyanova, Sun, Hove, Wong & Rouse, 2015, n. sp.
No full textSemivermilia lylevaili n. sp. (Figs 20, 21) Material examined. Holotype: specimen in tube fragment (Fig. 20 A) AM W. 47579, stn.G 237, Patch Reef near Palfrey Island, coll. G. Rouse & E. Kupriyanova, 30 Oct 2005. Paratypes: AM W. 47458 (2 without tubes), stn.G 241, off Osprey Island, coll. G. Rouse & E. Kupriyanova, 31 Oct 2005; AM W. 47582 (1 used for SEM), stn.G 244, off South Island, coll. G. Rouse & E. Kupriyanova, 2 Nov 2005; SAM E 3629, stn.G 237, Ser 59, Patch Reef near Palfrey Island, coll. G. Rouse & E. Kupriyanova, 30 Oct 2005. Additional material: AM W. 45076, MI QLD 2417 (5); AM W. 45077, MI QLD 2417 (2); AM 47631, MI QLD 2386; AM W. 47632, MI QLD 2352; AM W. 47633, MI QLD 2406. Description. TUBE: white, about 0.4 mm wide, with lumen of 0.3 mm. Circular in cross section, with two not very distinct longitudinal ridges (Fig. 20 A), without flaring peristomes; granular overlay absent. BRANCHIAE: with 5–6 pairs of radioles, arranged short pectinately, not connected by inter-radiolar membrane. Branchial eyes absent (Fig. 20 B, C). PEDUNCLE: smooth, circular in cross section, inserted just below first and second normal radiole; without wings, clearly separated from opercular ampulla by a constriction (Fig. 20 B, C). OPERCULUM: slightly asymmetrical, with simple convex thin brownish endplate, terminal spine absent (Figs 20 A–C, 21 A). Pseudoperculum absent. COLLAR AND THORACIC MEMBRANES: collar relatively high, trilobed, continuous with thoracic membranes ending at 2 nd thoracic chaetiger (Fig. 21 A). THORAX: with collar chaetiger and 6 uncinigerous chaetigers. Tori positioned along mid-line, triangular depression absent. Collar chaetae limbate of two sizes (Fig. 21 B). Subsequent chaetae limbate, of two sizes, with Apomatus chaetae starting at chaetiger 3 (Fig. 21 C). Uncini saw-to-rasp shaped, with up to 15 teeth in profile view and up to 4 teeth in the row above the wide gouged peg (dental formula depending place in row from P: 4: 4: 2: 1: 2: 2: 1: 1: 1, 9 in profile view, to P: 4: 3: 2: 2: 2: 1: 1: 1: 1: 1: 1: 1: 1: 1, 14 in side view) (Fig. 21 D). ABDOMEN: abdominal chaetigers up to 30. Uncini rasp-shaped, with 8–10 rows of 7 – 3 teeth each above wide, slightly crenulated peg (Fig. 21 F). Chaetae narrow flat geniculate with rounded teeth (Fig. 21 E). Achaetous anterior abdominal zone short. Posterior glandular pad absent. Long posterior capillary chaetae absent (Fig. 21 A). SIZE: length up to 1.6 mm, width of thorax 0.2 mm. Branchiae and operculum accounting for 1 / 3 of entire length. COLOUR: orange to yellow (Fig. 20). Etymology. The species is named after Dr Lyle Vail, director of LIRS. Remarks. By its simple operculum, this new species resembles S. annehoggettae n. sp., but lacks distinct elongated ovicells typical for the latter species. Reproduction. Lecithotrophic larvae brooded inside the tube. Type locality. Lizard Island, Qld, Australia. Distribution. Qld, Australia.Published as part of Kupriyanova, Elena K., Sun, Yanan, Ten Hove, Harry A., Wong, Eunice & Rouse, Greg W., 2015, Serpulidae (Annelida) of Lizard Island, Great Barrier Reef, Australia, pp. 275-353 in Zootaxa 4019 (1) on page 315, DOI: 10.11646/zootaxa.4019.1.13, http://zenodo.org/record/28949
Osedax talkovici Rouse & Goffredi & Johnson & Vrijenhoek 2018, n. sp.
No full textOsedax talkovici n. sp. Figure 3 ‘yellow patch’ (Rouse et al. 2011; Rouse et al. 2015; Vrijenhoek et al. 2009) Material examined. Holotype: SIO-BIC A 7821 female (GenBank COI sequence MG262313), fixed in glutaraldehyde-preserved in ethanol, collected from turkey (Meleagris gallopavo) bone deployed at 1018 meters depth in Monterey Submarine Canyon, California (36°46.308’N; 122° 4.981’W) ROV Doc Ricketts dive number 233, June 2, 2011. Paratypes: Females, all fixed in formalin-preserved in ethanol, SIO-BIC A1649 (GenBank COI sequence FJ347621), SIO-BIC A7822, A7823, A7824, A7825, A7826 (GenBank COI sequences FJ347620, 431196, 431197, 431201, 431205), whale (Eschrichtius robustus) deployed at 633 meters depth in Monterey Submarine Canyon, California (36°48.178’N; 121°59.677’W) ROV Tiburon dive number 1160, Dec. 18, 2007; Female SIO-BIC A7829 (GenBank COI sequence MG262311) and dwarf males (allotypes) SIO-BIC A7830 whale fall at 633 meters depth in Monterey Submarine Canyon, California (36°48.178’N; 121°59.677’W) ROV Doc Ricketts dive number 205, October 26, 2010; Female SIO-BIC A7827 (GenBank COI sequence MG262310) and dwarf males (allotypes) SIO-BIC A7828, whale (Eschrichtius robustus) deployed at 633 meters depth in Monterey Submarine Canyon, California (36°48.178’N; 121°59.677’W) ROV Doc Ricketts dive number 233, June 2, 2011; Female SIO-BIC A7831 (GenBank COI sequence MG262312) on green turtle bone (Chelonia mydas), deployed at same locality and date as holotype. Diagnosis and description. Holotype female (Figs 3B, C); in life trunk 1.8 mm long, 0.3 mm wide; crown of palps contracted, 1.5 mm long. Tube gelatinous. Oviduct 0.75 mm (Figs 3C, D). In life, palps reddish with blood (Figs 3A–E). Pinnules of all four palps oriented dorsally (Figs 3A, D, E). Trunk with bright yellow patch on midventral anterior edge (Figs 3A, B, D). Clear demarcation into upper and lower trunk (Fig. 3D). Ovisac spheroidal in holotype (Figs 3B, C), extending laterally, or as simple lobes in other specimens. Roots of holotype longer that the remaining body, extending posteriorly as a single lobate mass (Figs 3B, C). In other specimens (Figs 3A, D, E), roots as simple lobes or extending laterally in two lobes. Males dwarfs, resembling trochophore larvae, with spermatids and sperm (Figs 3F, G). Distribution. Known from Monterey Bay, California from 633 to 1018 meters depth (Table 2). It has been found in whale, elephant seal, cow, turkey, turtle and teleost bones. Etymology. This species is named (noun in the genitive case) for Mark Talkovic, Senior ROV pilot for MBARI, who collected many bones containing Osedax over the years. Remarks. Osedax talkovici n. sp. is part of Osedax Clade I and forms a well-supported clade with the undescribed species O. ‘mediterranea’ and a clade comprised of Osedax sigridae n. sp. and the undescribed species O. Sagami-5 (Fig. 1). It has a minimum uncorrected distance, for COI, of at least 16% from each of these (Table 4). The 15 available COI sequences for Osedax talkovici n. sp. (Table 3) show less that 1% sequence divergence. The most distinguishing feature of Osedax talkovici n. sp. is the bright yellow patch ventrally on the anterior trunk (Fig. 3).Published as part of Rouse, Greg W., Goffredi, Shana K., Johnson, Shannon B. & Vrijenhoek, Robert C., 2018, An inordinate fondness for Osedax (Siboglinidae: Annelida): Fourteen new species of bone worms from California, pp. 451-489 in Zootaxa 4377 (4) on pages 460-462, DOI: 10.11646/zootaxa.4377.4.1, http://zenodo.org/record/116587
Osedax knutei Rouse & Goffredi & Johnson & Vrijenhoek 2018, n. sp.
No full textOsedax knutei n. sp. Figure 6 ‘nude-palp-E’ (Rouse et al. 2011; Rouse et al. 2015; Vrijenhoek et al. 2009; Worsaae et al. 2016) Material examined. Holotype: SIO-BIC A 7812, Female (GenBank COI sequence FJ347635), fixed in formalin preserved in ethanol, collected from whale fall (Balaenoptera musculus) deployed at 1018 meters depth in Monterey Submarine Canyon, California (36°46.308’N; 122° 4.981’W), ROV Tiburon dive number 1049, Oct. 25, 2006; Allotype, dwarf male from tube of holotype SIO-BIC A7813. Paratypes: All females, fixed in formalin preserved in ethanol; SIO-BIC A1646 (GenBank COI sequence FJ347634), SIO-BIC A7814, (GenBank COI sequence FJ347632), same locality and date as holotype; SIO-BIC A7815, (GenBank COI sequence JF509952), collected from fish bones deployed at 1018 meters depth in Monterey Submarine Canyon, California (36°46.308’N; 122° 4.981’W), ROV Doc Ricketts dive number 209, Oct. 29, 2010; SIO-BIC A7816, (GenBank COI sequences MG262306), collected from turkey (Meleagris gallopavo) bone deployed at 1018 meters depth in Monterey Submarine Canyon, California (36°46.308’N; 122° 4.981’W), ROV Doc Ricketts dive number 233, June 2, 2011. Diagnosis and description. Holotype female preserved partially dissected from whale bone (Fig. 6A); trunk contracted 1.6 mm long, 0.3 mm wide; crown of apinnulate palps contracted, 2.3 mm long. Tube not kept for holotype, but forms a tight sheath in other specimens, from which palps emerge. Oviduct not visible in holotype (Fig. 6A), but is slightly shorter (1.5 mm) than contracted palps in paratype SIO-BIC A7816, and much shorter than extended palps in live specimen spawning eggs (Fig. 6D). In life, palps reddish with two blood vessels each (Fig. 6E). Trunk with no obvious pigmentation or demarcation into upper and lower trunk (Figs 6A, D). Ovisac represented as lobes on either side of trunk in holotype, extending laterally, or as long lobes in other specimens. Roots of holotype longer that the remaining body, extending in several directions (Fig. 6A). In other specimens, roots also extend in various directions (Fig. 6D). Males dwarfs, 450 µm long by 100 µm wide, with anterior prototroch and sperm, two posterior expanded segments bearing hooked chaetae (Figs 6B, C). Distribution. Known from Monterey Bay, California from 1018 to 2898 meters depth (Table 2). It has been found in whale, cow, turkey and teleost bones. Etymology. This species is named (noun in the genitive case) for Knute Brekke, Chief ROV pilot for MBARI, who expertly collected many bones and Osedax over the years. Remarks. Osedax knutei n. sp. is part of Osedax Clade II and closest relative to Osedax westernflyer n. sp, (Fig. 1) with a minimum uncorrected distance for COI of 16% (Table 4). Twelve COI sequences for Osedax knutei n. sp. (Table 3) generally showed less that 1.2% sequence divergence from each other. An exceptional sequence (JF509952) from paratype SIO-BIC A7815 dissected from fishbone (Rouse et al. 2011), diverged by 3.2% to 4.5% from the other Osedax knutei n. sp. specimens (see example distance in Table 4). The tentative assignment of paratype SIO-BIC A7815 to Osedax knutei n. sp. requires further investigation. Two new COI sequences for Osedax knutei n. sp. were also deposited on GenBank for which no voucher specimens were retained; MG262305 was recovered from a fishbone deployed at 2898 meters and MG262307 was from a turkey deployed at 1018 metersPublished as part of Rouse, Greg W., Goffredi, Shana K., Johnson, Shannon B. & Vrijenhoek, Robert C., 2018, An inordinate fondness for Osedax (Siboglinidae: Annelida): Fourteen new species of bone worms from California, pp. 451-489 in Zootaxa 4377 (4) on pages 465-468, DOI: 10.11646/zootaxa.4377.4.1, http://zenodo.org/record/116587
Semivermilia annehoggettae Kupriyanova, Sun, Hove, Wong & Rouse, 2015, n. sp.
No full textSemivermilia annehoggettae n. sp. (Figs 18, 19) Semivermilia spec. —ten Hove & Kupriyanova 2009: 21 fig. 7 D [Lizard Island, Qld; SEM of double hollow chambers]. Type material. Holotype: AM W. 47575, stn.G 236, east lagoon near Bird Islet, 9 m, coll. G. Rouse & E. Kupriyanova, 29 Oct 2005, specimen in tube with partly damaged ovicells. Paratypes: AM W. 47576, stn.G 240, Osprey Island, intertidal rubble zone, coll. G. Rouse & E. Kupriyanova, 31 Oct 2005 (3 plus 3 used for SEM). Other material examined. AM W. 28200 (7 plus tubes on granite rock), stn. 19, Turtle Beach, intertidal, boulders and cobbles in coarse sand, coll. H. ten Hove, 5 Mar 1986; AM W. 28325 (2, tube fragments only), between Lizard Head and Coconut Beach, undersides of boulders on rock, little sand, low tide, coll. H. ten Hove, 23 Jun 1983; AM W. 28418 (as Pseudovermilia), lagoon, coll. J. Anderson, 22 Jun 1983; AM W. 45411, MI QLD 2386; AM W. 47577 (tube with ovicells), stn.G 232, between First Beach and Osprey Island, coral rubble, snorkeling, 1 m, coll. G. Rouse & E. Kupriyanova, 26 Oct 2005; AM W. 47578 (3), stn.G 241, off Osprey Island, coll. G. Rouse & E. Kupriyanova, 31 Oct 2005; SAM E 3628, Ser 54, stn.G 240, Osprey Island, intertidal rubble zone, coll. G. Rouse & E. Kupriyanova, 31 Oct 2005; ZMA V.Pol. 4796 (4 + 4?), between First Beach & Osprey Island, reef flat, dead corals & rubble in sand, 3–4 m, coll. H. ten Hove, 17 Jun 1983; ZMA V.Pol. 5533 (2), stn. 16, North Point, sloping reef, mainly dead, slightly silted corals, 3–17 m, coll. H. ten Hove, P. Hutchings & M. Reid, 1 Mar 1986; ZMA V.Pol. 5534 (13, as Semivermilia spec.), North Reef, 14 ° 40 'S, 145 ° 27 'E, underside of boulders on rock, low tide, little sand, coll. H. ten Hove, 22 Jun 1983; ZMA V.Pol. 5535, stn. 18, lagoon near east entrance, sheltered side of reef, near sandy bottom, 2–20 m, coll. H. ten Hove, 3 Mar 1986 (separated from ZMA V.Pol. 4776, Pseudovermilia or Semivermilia spec.); ZMA V.Pol. 4800 (10), Granite Head, 14 ° 39 'S, 145 ° 27 'E, from underside of boulders on rock, little sand, subtidally, coll. H. ten Hove, 18 Jun 1983; ZMA V.Pol. 4806 (12), Mermaid Cove, underside boulders in surf, subtidal & low intertidal, coll. H. ten Hove, 20 Jun 1983. Description. TUBE: white, about 0.4 mm wide, with lumen of 0.3 mm; anteriorly with double hollow chambers on top (Fig. 18 A–D). If broken, these chambers may appear as three separate thin sharp longitudinal keels. BRANCHIAE: with 5–6 pairs of radioles, arranged pectinately, not connected by inter-radiolar membrane. Branchial eyes absent. PEDUNCLE: smooth, circular in cross section, inserted as second radiole; without distal wings, clearly separated from opercular ampulla by constriction (Fig. 18 C). OPERCULUM: simple semi-transparent inverted cone, sometimes inner vesicle visible inside, with flat, also (semi-)transparent endplate or just flat surface (Figs 18 B, C; 19 A). Pseudoperculum absent. COLLAR AND THORACIC MEMBRANES: collar trilobed, continuous with short thoracic membranes ending at 2 nd thoracic chaetiger. THORAX: with collar chaetiger and 6 uncinigerous chaetigers (Fig. 19 A). Tori positioned along mid-line, triangular depression absent. Collar chaetae limbate, of two sizes (Fig. 19 B). Subsequent chaetae limbate, of two sizes, Apomatus chaetae starting at chaetiger 3 (Fig. 19 C). Uncini saw-to-rasp shaped, with up to 15 teeth in profile view and up to 4 teeth in the row above the wide gouged peg (dental formula P: 5: 4: 3: 3: 2: 1: 1: 2: 2: 1: 1: 1: 1: 1) (Fig. 19 D). ABDOMEN: abdominal chaetigers up to 30. Uncini rasp-shaped, with up to 12 teeth in profile view and up to 6 rows of teeth above wide gouged (Fig. 19 E). Anterior chaetae and posterior capillary chaetae not observed (see Remarks). Posterior glandular pad absent. SIZE: length up to 2 mm, width of thorax up to 0.2 mm. Branchiae and operculum accounting for 1 / 3 of entire length. COLOUR: white to yellowish (Fig. 18 B, C). Etymology. The species is named after Dr. Anne Hoggett, the director of LIRS. Remarks. This small species occurs cryptically, it is reminiscent of S. pomatostegoides, but with very different operculum, simple transparent inverted cone lacking any chitinous enforcement. The most distinct character of this species is the tube with one or several consecutive pairs of hollow "pipes" anteriorly. These hollow chambers on top break easily and only rarely remain intact, but the remaining tube, with its flattened chambered sides, is typical enough. The function of these pipes is unclear, they clearly resemble brood chambers found in other small serpulids, but we actually observed lecithotrophic larvae of various stages (Fig. 19 G) being brooded inside the tubes proper, not in the chambers. The thoracic uncini are saw-to-rasp shaped, which is typical for Semivermilia. Abdominal chaetae were looked for under SEM in three specimens, but not observed, so assumed absent. Reproduction. Lecithotrophic larvae brooded inside the tube, no larvae were found inside paired ovicells. Type locality. Lizard Island, Qld, Australia. Distribution. Qld, Australia.Published as part of Kupriyanova, Elena K., Sun, Yanan, Ten Hove, Harry A., Wong, Eunice & Rouse, Greg W., 2015, Serpulidae (Annelida) of Lizard Island, Great Barrier Reef, Australia, pp. 275-353 in Zootaxa 4019 (1) on pages 312-315, DOI: 10.11646/zootaxa.4019.1.13, http://zenodo.org/record/28949
Phyllochaetopterus lauensis Rouse, 2007, new species
No full textPhyllochaetopterus lauensis new species (Figs. 1–4) Material Examined.— Holotype (SAMA E 3672), complete, with a tube twice the length of the body and 2 paratypes (SAMA E 3673, OMNH-Iv 5025) complete, with fragments of tube, 5 paratypes (CBM-ZW- 1006, SAM E 3674, SIO-BIC-A 976 and A 977, USNM 1106928) incomplete, with a fragment of tube, 1 paratype (USNM 1106929) incomplete, without tube. Holotype and 8 paratypes were collected during dive 145 of the Deep-Sea Research Vehicle (DSV) Jason II at the hydrothermal vent locality known as Hine Hina, Southern Valu Fa Ridge, Lau back-arc basin 22 ° 31.9393S; 176 ° 43.1038W near Tonga on 22 May, 2005, a cluster of chaetopterid tubes was collected by manipulator at 1818 m depth in the vicinity of hydrothermal vents. Additional material examined: For comparison the following Phyllochaetopterus specimens from the Pacific area were also studied: Phyllochaetopterus cf. verrilli Treadwell, 1943: CMNH-ZW-(uncatalogued), Sesoko Island, Okinawa Island, sandy mud flat, 1–2 m deep, February 1987, by E. Nishi. Phyllochaetopterus claparedii McIntosh, 1885: CMNH-ZW-(uncatalogued), Tateyama, Boso Peninsula, 5 to 6m m deep, sandy bottom, by E. Nishi, 15 October 1998. Phyllochaetopterus. sp.: CMNH-ZW (uncatalogued), Port Jackson, Bottle and Glass Rocks, Sydney Harbour, Australia, 33 ° 58 S, 151 0 0 E, 4 m. depth, 4 April 1999 by G. W. Rouse. Diagnosis.— Phyllochaetopterus of small size, eyes absent; A 1 dorsally with short ‘cirri’ with slightly protruding internal chaetae; A 4 with 1–2 stout brown cutting chaetae, pear-shaped in frontal view, head of chaeta slightly inflated, with row of small teeth on both lateral edges. Region B with two chaetigers; B notopodia foliaceous, bilobed; B neuropodia each with single band of uncini; C notopodia digitiform, with single protruding chaeta; C neuropodia bilobed, with two bands of uncini anteriorly, with single band posteriorly. Body formula of species: 9–10 A+ 2 B+ at least ca. 40 C = ca. 52 or more chaetigers; Region A 5 –A 9 of plastron (glandular ventral shield) with distinctive light brown (A 5), whitish (A 6 –A 7), and light brown (A 8 and A 9) transverse bands observed in alcohol-preserved specimens. Tube transparent or translucent, partly amber to white in color, weakly annulated, without septa or partitions. Description (based on holotype). — Holotype complete (some paratypes lacking posterior part of region C), 26 mm long excluding palps; palps, paired 6mm long (about 5 to 8 mm long in paratypes), grooved, arising from near posterolateral border of prostomium (Fig. 3 A). Body 1.0–1.4 mm wide at ventral shield. Body creamy white except for ventral shield in alcohol preserved specimens. Region A narrow, 1.0-1.2mm width, 5.0 mm long for 9 chaetigers (10 chaetigers in some paratypes and 4.0 to 5.0 mm length). Prostomium a distinct lobe, peristomium broad and plate-like, appearing slightly cleft when viewed from ventral side (Fig. 3 A, B, C). Eyespots absent. Cirri of 1 st chaetiger small and short (Fig. 3 A, E), with slightly protruding internal chaetae. Dorsal groove ciliated, extending from base of palps along body regions A, B and C (Fig. 3 E). Ventrum of region A with a long slender plastron (ventral glandular shields), separated into 4 sections based on color (Fig. 3 A, B, C), color of each section varying among type specimens. In holotype, Section I, longer than others, from peristomium to chaetiger A 4 or anterior A 5, white in holotype (Fig. 3 B). In some paratypes (Fig. 3 A and C), pale, very light brown. Section II, chaetiger A 5 only or A 5 to A 6 (Figs. 3 A,C), dark brown in holotype, light or dark brown in paratypes. Section III comprises chaetigers A 6 to A 7 or A 7 only, pale white in holotype and paratypes (Fig. 3 A, B, C). Section IV comprises A 8 and A 9 (plus A 10 in some paratypes) (A 8- 10 in Fig. 3 A; A 7–9 in Fig. 3 B; A 9 in Fig. 3 C), light brown anteriorly and progressively lighter in color in posteriorly in holotype and some paratypes (Fig. 3 A, B), no color in others (Fig. 3 C). In holotype and paratype (SAMA E 3673) Section II darker than anterior Section IV. Chaetigers A 1 to A 3 short, parapodia with a single row of 10 to 20 lanceolate chaetae; A 4 elongate, with one large (cutting) chaeta in each notopodium (one undeveloped chaeta in paratypes CBM-ZW 1006), and more than 10 lanceolate chaetae; A 5 to A 9 (or A 10 in some paratypes) slightly longer and wider than anterior three chaetigers, with single row of 20 to 30 lanceolate chaetae. Cutting chaetae of A 4 with obliquely ellipsoidal distal end; head slightly inflated, slightly wider than shaft, pear-shaped in frontal view, tip slightly pointed (Fig. 4 F, G, H); shaft nearly semi-circular in horizontal section, lateral or ventral grooves absent. Total length of cutting chaetae 300-400 m; head ca. 80 m in width, 90 m in length (Figs. 2 A, B, C, 4 F, G, H). Middle region (region B) comprises 2 chaetigers only, each slightly longer than anterior chaetigers; notopodia bilobed, dorsal lobe branched into a Y-shape (= dichotomously branched) (Fig. 3 A, B, C, D). Paddle and cupule absent. B 1 and B 2 nearly same length. Beneath last A chaetiger and first B notopodia, a pair of liquidfilled swellings present (Fig. 3 D). B-region neuropodia unilobed with one row of minute uncini: uncini nearly triangular, with ca. 25 teeth (Fig. 4 J). Posterior region (region C) with 25 chaetigers in holotype (up to 40 chaetigers in three paratypes, though incomplete). Anterior C-region chaetigers elongate, extended and longer than regions A and B chaetigers (Figs. 3 A, 4 A). Notopodia unilobed, knob-like tip each with a single chaeta (Fig. 4 A, B, C). Neuropodia bilobed in anterior 10 to 12 chaetigers (Fig. 4 A, B) and unilobed in posterior chaetigers (Fig. 4 C). Uncini similar to those of region-B, but smaller. Tube fragile, 1.5 to 2.0 mm in diameter, slender, nearly straight, weakly annulated and pleated in parts. Tube wall thin, transparent, partly light amber to light brown. Septa or partitions absent. Etymology.—The species epithet lauensis is derived from the name of the type locality, the Lau back-arc basin. Remarks. —Among the Phyllochaetopterus, P. lauensis n. sp. is easily distinguishable from other members of the genus by its alternating white/brown patterning on the plastron. Similar patterning is found in Spiochaetopterus spp. (e.g., Bhaud, 1998; Nishi et al., 2004), and the feature is used for distinguishing among the species of this genus. In Phyllochaetopterus, however, the ventral shield (glandular area) is usually a single color or separated into only two colored portions, anterior and posterior. For Phyllochaetopterus in general, the A 4 chaetal numbers and color, the number of region-B chaetigers and tube characters are used for distinguishing species. Based on those characters, we provide here a summary table (Table 1). *H.-S. = Hartmann-Schröder Among the 19 previously described species of Phyllochaetopterus, twelve species have 1–2 cutting chaetae on notopodia of A 4, while others have a row of 3–8 cutting chaetae (Table 1, Bhaud 1977, Kudenov 1975). These taxa can also be distinguished further by the number of region-B chaetigers and separated into four groups (Table 1): A—having 1–2 cutting chaetae in A 4 notopodia, with two region-B chaetigers; B—having 1–2 cutting chaetae in A 4, with three or more region-B chaetigers; C—having a row of more than 6 cutting chaetae in A 4, with two region-B chaetigers; D—having more than 6 cutting chaetae in A 4, with three or more region-B chaetigers. Phyllochaetopterus lauensis n. sp. belongs in group A, which now contains 4 described species; P. gracilis Grube, 1863, P. claparedii McIntosh, 1885, P. limicolus Hartman, 1960 and P. monroi Hartman, 1967. Apart from all other Phyllochaetopterus lacking the marked patterning described here for P. lauensis n. sp., Phyllochaetopterus gracilis has 10–11 region-A chaetigers whereas P. lauensis n. sp. has only 9–10. Phyllochaetopterus limicolus lacks the inflated head in A 4 modified chaetae (Bhaud 1977) seen in P. lauensis n. sp. (Fig. 2 B, C). Phyllochaetopterus claparedii is morphologically most similar to P. lauensis n. sp., but the former has long, clavate cirri on A 1 and region-B chaetigers are elongate and longer than those of region A (McIntosh 1885). Phyllochaetopterus lauensis n. sp. on the other hand has short cirri on A 1, and region-B chaetigers are not especially elongate (Fig. 3 A, E). Additionally, P. lauensis n. sp. is also distinguishable from P. claparedii by the number of chaetae in the C notopodia; P. claparedii and P. aciculigerus have 3–4 chaetae in posterior C notopodia and all other species of the genus have only a single chaeta. P. monroi Hartman has minute papillae at the base of C notopodia, whereas P. lauensis n. sp has no such papillae. We also compared the new species to specimens of P. claparedii collected at Tateyama, Boso Peninsula, Chiba Prefecture, particularly with regards to the A 4 chaetal structure using scanning electron microscopy. Phyllochaetopterus lauensis n. sp. and P. claparedii both have 9–10 A+ 2 B, and 1–2 A 4 cutting chaetae with a slightly inflated head with a slanting edge in lateral view (Fig. 2 A, F). However, in frontal view the A 4 cutting chaetae of P. lauensis are pear-shaped (Fig. 2 A–C) and those of P. claparedii are asymmetrically cordate - a skewed heart shape (Fig. 2 E, F).Published as part of Rouse, Eijiroh Nishi Greg W., 2007, A new species of Phyllochaetopterus (Chaetopteridae: Annelida) from near hydrothermal vents in the Lau Basin, western Pacific Ocean, pp. 55-64 in Zootaxa 1621 on pages 56-62, DOI: 10.5281/zenodo.17920
A Preliminary Structural and Micropalaeobotanical Investigation of some Uppermost Cretaceous Coals from Western Canada
No full textTitle: A Preliminary Structural and Micropalaeobotanical Investigation of some Uppermost Cretaceous Coals from Western Canada, Author: Glenn E. Rouse, Location: ThodeA preliminary examination of the structural features and plant microfossils which characterize coals from thin seams in the Uppermost Cretaceous formation of western Alberta. Descriptions of the structural units and microfossils are complemented by quantitative appraisals of plant microfossil associations. Suggestions of probable floral components which existed during Uppermost Cretaceous imps and possibilities of seam correlation and separation are forwarded. Illustrated by five photographic plates.ThesisCandidate in Philosoph
Osedax packardorum Rouse & Goffredi & Johnson & Vrijenhoek 2018, n. sp.
No full textOsedax packardorum n. sp. Figure 16 ‘orange collar’ (Braby et al. 2007; Rouse et al. 2009; Rouse et al. 2015; Tresguerres et al. 2013; Vrijenhoek et al. 2009) ‘sp.4 SBJ-2006’ (GenBank COI sequence DQ996639, DQ996641-2) Material examined. Holotype: Female, fixed in formalin preserved in ethanol, SIO-BIC A 1641 (GenBank COI sequence EU223341), collected from whale carcass (Balaenoptera musculus) deployed at 1018 meters depth in Monterey Submarine Canyon, California (36°46.308’N; 122° 4.981’W), ROV Tiburon dive number 1049, Oct. 25, 2006. Paratypes: Female and dwarf males (allotypes), fixed in formalin preserved in ethanol SIO-BIC A7840, A7842 (female GenBank COI sequences EU223339, EU223343), same locality and date as holotype; Female, fixed in formalin preserved in ethanol, SIO-BIC A7841(GenBank COI sequence EU223340), same locality and date as holotype; Female, sectioned for histology, same locality and date as holotype, SIO-BIC A7843 (GenBank COI sequence EU223342); Female, fixed in formalin preserved in ethanol, SIO-BIC A7844 (GenBank COI sequence FJ431200), collected from whale fall (Eschrichtius robustus) at 663 meters depth in Monterey Submarine Canyon, California (36°48.178’N; 121°59.677’W) ROV Tiburon dive number 1160, Dec. 18, 2007. Diagnosis and description. Holotype female, in life trunk 11 mm long, 0.6 mm wide; crown of palps contracted, curled, 2 mm long (image not shown as the trunk is damaged). Palps up to 12 mm long when extended in other specimens (Figs 16A, B). Pinnules of all palps oriented dorsally and the oviduct lying between the dorsalmost pair of palps (Figs 16B, D, E). Oviduct extends from trunk into crown for 3 mm (Fig. 16B). In life, palps reddish with two major blood vessels in each (Figs 16A, B). Tube a gelatinous loose mass around trunk (Figs 16A, B). Trunk with pale to dark orange ring around anterior margin; ring broken mid-dorsally by oviduct and midventrally by and oval unpigmented patch (Figs 16A, B, E). Internally trunk shows extensive musculature and glands with prominent dorsal and ventral blood vessels (Fig. 16G). Ovisac in holotype an ellipsoidal mass (not shown); extending laterally as lobes in other specimens (Fig. 16C). Roots of holotype extend from ovisac on one side as one mass; in other specimens, roots as long branching masses. Males dwarfs, with spermatids and sperm (Figs 16F, G), chaetal-bearing segments not inflated (Fig. 16H); found in tube lumen of females. Distribution. Known from Monterey Bay, California at 349, 633, and 1018 meters depths (Table 2). Found in whale and cow bones. Etymology. This species is named (noun in the genitive case) in honor of the Packard family whose foundation supports MBARI and enabled the discovery of all of the Osedax species in California. Remarks. Osedax packardorum n. sp. is part of Osedax Clade IV and closest relative to Osedax lehmani n. sp., (Fig. 1), from which it has a minimum uncorrected distance for COI of 8-9% (Table 4). As pointed out above, this is one of the smaller interspecific distances among Osedax species and the two species are morphologically very similar. All 27 available COI sequences for Osedax packardorum n. sp. (Table 3) comprise less than 1% sequence divergence. The most distinguishing feature of Osedax packardorum n. sp. is the orange ring around the anterior part of the trunk. (Fig. 16 A-C, E).Published as part of Rouse, Greg W., Goffredi, Shana K., Johnson, Shannon B. & Vrijenhoek, Robert C., 2018, An inordinate fondness for Osedax (Siboglinidae: Annelida): Fourteen new species of bone worms from California, pp. 451-489 in Zootaxa 4377 (4) on pages 479-481, DOI: 10.11646/zootaxa.4377.4.1, http://zenodo.org/record/116587
Synthesis and characterisation of lanthanide and other inorganic framework materials
No full textFive new cerium (IV) fluoride and fluoride–arsenate framework structures have been synthesised through hydrothermal techniques using CeF4 as a fluoride source. Cs[CeIV2F8[F.H2O]] (I) consists of layers, formed from linked Ce(F,O)n polyhedra cross-linked by hydrogen bonding that defines channels containing the caesium ions. [(NH4)5(H2O)2][CeIV4(AsO4)6(H2O)F3] (II), has an open framework structure with large channels filled with NH4+ cations and H2O molecules. CeIV[AsO4]F (III) and CeIV[AsO4]F[H2O] (IV) exhibit two types of bridging (Ce–O–Ce and Ce–F–Ce) bonds between Ce(O,F)n polyhedra, and (NH4)[CeIVF2(AsO4)] (V), is isostructural with the previously reported fluoride-phosphate (NH4)[CeIVF2(PO4)].The use of metal tetra-fluorides (MF4; M = Zr, Hf) in hydrothermal reactions, has led to the production of new structures that incorporate either phosphate or arsenate oxotetrahedra linking metal oxo-fluoro polyhedra. This new synthetic pathway has provided a safer route to formation that does not require the addition of the dangerous HF reagent. Seven new zirconium and four hafnium arsenate or phosphate materials have been identified including ZrIV(HAsO4)(AsO4)(NH4) (VI) a three-dimensional framework with NH4+ within the channels, ZrIV(AsO4)F(H2O) (VII) exhibits Zr-F-Zr linkages, ZrIV(HAsO4)2 a novel three-dimensional framework (VIII) and ZrIV2(AsO4)3(NH4)(H2O) (IX) analogous to the mineral Langbeinite. Organic amines included in the reaction mixture can template the frameworks and form cavities, as observed within the channels of HfIV2F(HAsO4)(AsO4)2[Temp-Hn]1/n(H2O)1.5 (XIII) (Temp = ethylenediamine/diethylenetriamine). The substitution of fluoride ions for oxygen in the metal polyhedral unit has produced variations in the dimensionality of the materials formed as fluoride is more frequently incorporated as terminating species, reducing framework dimensionality. The controlled addition of these fluoride species, has provided a route to the rational design of one, two and three-dimensional framework structures.Hexagonal lanthanide phosphates (LnIIIPO4.nH2O) with the mineral Rhabdophane structure type were synthesised through hydrothermal techniques and analysed upon heating where a distinct increase in the a-axis lattice length was observed upon dehydration of the structure. Variable-temperature X-ray diffraction, EDX, TGA and fluorescence studies were undertaken to illustrate the interaction between the lanthanide cations and the water molecules that reside within the channels of the framework
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