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Description of Antho (Plocamia) bremecae sp. nov. and checklist of Microcionidae (Demospongiae: Poecilosclerida) from Burdwood Bank and neighboring areas, SW Atlantic Ocean
No full textBarbara, Calcinai (2017): Description of Antho (Plocamia) bremecae sp. nov. and checklist of Microcionidae (Demospongiae: Poecilosclerida) from Burdwood Bank and neighboring areas, SW Atlantic Ocean. Zootaxa 4312 (3): 580-594, DOI: https://doi.org/10.11646/zootaxa.4312.3.1
Antho (Plocamia) bremecae Barbara 2017, sp. nov.
No full textAntho (Plocamia) bremecae sp. nov. Figures 2 and 3 Material examined. Holotype and 2 paratypes. The holotype was deposited at the Museo di Storia Naturale di Genova (MSNG), Italy (MSNG n° 59505), while two paratypes were deposited at the Museo Argentino de Ciencias Naturales “ Bernardino Rivadavia ” (MACN), Buenos Aires, Argentina (MACN-In 41003). Samples were labeled together as NBP 05/08 TB 4 #30 during the cruise; this was the station 4 (54° 44.02’S and 62° 12.98’ W); 804 m. Collection date: April 2008. Collector: Laura Schejter Type locality. West slope of Burdwood Bank, SW Atlantic Ocean (54° 44.02’S and 62° 12.98’ W); 804 m (Figure 1). Diagnosis. Flabellate Antho (Plocamia) species characterized by long choanosomal styles, ectosomal subtylostyles and long toxas. The main skeleton is reticulated, made by dumbbell-shaped diactines and by choanosomal styles supporting the ascending tracts. Description. Flabellate, foliate sponge arising from a short peduncle and from an encrusting base (Figure 2 A); the holotype is 4.5 cm long in total; the peduncle is about 3 mm thick, and it was detached from the substrate. The two paratypes are flat and flabellate; one is about 4 cm long and the other is slightly broken, about 3 cm long. Both present small peduncles attached to dead scleractinian corals (Figure 2 A). The lamellae are about 3 mm thick. The preserved specimens are light brown colored and full of sediments. The consistency is hard. The sponge surface is microhispid due to the styles extending through it. Ectosome: Subtylostyles tangentially arranged and forming bundles protruding through the ectosome (Figure 2 B – D). Choanosome: Regular renieroid, isodictyal skeleton (Figure 2 E) of dumbbell-shaped diactines and of ascending, paucispicular tracts of choanosomal styles (two or three styles in the tracts), with little visible spongin. The meshes are made of one, two, up to four dumbbell-shaped diactines and are about 300 µm wide (Figure 2 F). Choanosomal styles pierce the ectosomal layer protruding through the surface (Figure 2 D). Spicules: slightly curved choanosomal styles with smooth or slightly microspined heads and hastate tips (Figure 3 A); thin ectosomal subtylostyles, straight or sometimes curved, or flexuous, with spined heads and hastate tips (Figure 3 B); dumbbell-shaped diactines, sometimes anisotylote (Figure 3 C); they are always with microspined, slightly enlarged heads, and scattered spines along the shaft. Smooth toxas in a large size range and variable in shape, U- and wing-shaped, with intermediate forms (Figure 3 D); palmate isochelae (Figure 3 E). Measurements are shown in Table 1. Distribution and habit. The species is currently known only from its type locality, in the slope of Burdwood Bank. The habit registered in the studied specimens is epibiotic, on dead corals. Etymology. The species is named in honor of Dr. Claudia Bremec, mentor of Dr. Laura Schejter. She also promoted the participation of Dr. Schejter onboard the R/V “Nathaniel B. Palmer” during the 2008 Expedition. Remarks. According to the World Porifera Database (WPD) (van Soest et al. 2016), species of the genus Antho are numerous (59). Recently, van Soest et al. (2013) resurrected the subgenus Plocamia Schmidt for Antho species having peculiar dumbbell spicules making the basal reticulation. Eleven species belong to this subgenus, but none of these are present in the Magellanic Province or in biogeographic regions nearby (Spalding et al. 2007). One species of subgenus Acarnia (previously considered a senior synonym of Plocamia) was described as A. (A.) inconspicua Desqueyroux for Central Chile. It differs from this new species in having an encrusting habit and different spicule features: it is characterized by large styles (403‒ 1020 x 21 µm), smooth tylostrongyles, and small styles (388 x 15 µm), and by palmate isochelae (22 µm) as microscleres. A species close to the new one here described is Antho (Plocamia) erecta (Ferrer Hernandez). This species is lamellate and has similar spicule features, with ectosomal subtylostyles, large styles, dumbbell-shaped spicules, toxas, and palmate isochelae; however, the shape of the spicules is different with the large styles being smooth, whereas toxas are oxhorn in form. Also, spicules are smaller than those of the new species. All the other species of subgenus Plocamia differ in shape and spicule features. Antho (P.) anisotyla (Lévi) described from Senegal, A. (P.) karykina (de Laubenfels) from Northern California, A. (P.) karyoka (Dickinson) from Mexican Tropical Pacific and A. (P.) manaarensis (Carter) from the Indian Ocean are characterized by shorter spicules: styles are 130–275 x 5–11 µm long and tylotes 125–185 x 7–8 µm long in A. (P.) anisotyla; choanosomal tylostyles are 165 x 20 µm, and toxas 45 µm in A. (P.) karykina; subtylostyles and strongyles are 340 x 18 and 175– 200 x 16–22 µm long respectively, tylostyles 160–200 x 3–12 µm, twisted palmate isochelae are 10–17 µm and toxas 18–80 µm long in A. (P.) karyoka; finally, styles are 600 x 21 µm, hair-like styles are 238 µm, tylotes 238 µm, toxas 50 µm and isochelae are 16.8 µm long in A. (P.) manaarensis. Antho (P.) arbuscula (Burton), from Yemen, has a small category of acanthostyles (50– 70 x 5–7 µm, and shorter spicules); A. (P.) gymnazusa (Schmidt) from Florida has larger spicules (smooth styles 2130–2480 x 44 µm, dumbbell-shaped spicules 470 x 63 µm, Ridley & Duncan 1881); A. (P.) hallezi (Topsent) from Western North Africa, has smaller spicules and contort isochelae. Antho (P.) lambei (Burton) was described for the North East Pacific Ocean, but unfortunately Burton gave only a short description of the species without spicules measurements. Given the unlikelihood of there being any shared species between the Magellanic and the Cold Temperate Northeast Pacific Provinces, Burton’s species is also deemed distinct from A. (P.) bremecae sp. nov.Published as part of Barbara, Calcinai, 2017, Description of Antho (Plocamia) bremecae sp. nov. and checklist of Microcionidae (Demospongiae: Poecilosclerida) from Burdwood Bank and neighboring areas, SW Atlantic Ocean, pp. 580-594 in Zootaxa 4312 (3) on pages 582-584, DOI: 10.11646/zootaxa.4312.3.11, http://zenodo.org/record/85564
Clathria (Microciona) antarctica
No full text<i>Clathria</i> (<i>Microciona</i>) <i>antarctica</i> (Topsent, 1917) <p>Figure 5</p> <p> <b>Material examined.</b> Two specimens (MSNG N° 59507, MACN IN-41005) were found at station 4, at 54° 44.02’S and 62° 12.98’ W; 804 m (labeled during the cruise as NBP 05/08 TB 4 #31). Collection date: April 2008. Collector: Laura Schejter.</p> <p> <b>Description.</b> Our specimens are massive, light brown to slightly grey, 64 x 23 x 24 mm (Figure 5 A). Spicules are 2 categories of styles (sometimes subtylostyles), occasionally basally-spined, 350–(415±45)–487 x 7.5 µm and 515–(603±50)–780 x 12.5–(17±3)–20 µm (Figure 5 B); acanthostyles (Figure 5 B, C), 105–(130±16)–146 x 5 – (8±2)–10 µm and short; thick and wing-shaped toxas, 45–(57±6)–71 µm (Figure 5 C–D). Few rare and big toxas (250–370 µm) were also found (Figure 5 D).</p> <p> <b>Distribution.</b> This species has a wide distribution in the SW Atlantic Ocean and southern Pacific, recorded from Antarctic waters, South Georgia Islands, Malvinas (Falklands) Islands, off Buenos Aires and Uruguay, Macquarie Island and New Zealand, (Hooper 2009; Schejter <i>et al</i>. 2011). This is the first record for Burdwood Bank.</p> <p> <b>Remarks.</b> The synonymy of this species comprises ten alternative names (Hooper 2009) which may reflect the intrinsic variability of the species. Koltun (1976) synonymized <i>Stylostichon tuberculata</i> Burton, <i>Clathria pauper</i> Brøndsted and <i>Microciona basispinosa</i> Burton together with <i>Pseudanchinoe toxifera</i> (Topsent). Later, Hooper (1996) demonstrated that “ <i>antarctica ”</i> should be used against “ <i>toxifera</i> ”, and confirmed the synonymy between “ <i>basispinosa</i> ” and “ <i>toxifera</i> ”, rejecting the inclusion of <i>C. pauper;</i> however, he did not confirm the inclusion of “ <i>tuberculata</i> ” because the types were not found. Also, the new combination proposed for this taxon was <i>Clathria</i> (<i>Microciona</i>) <i>antarctica</i> (Topsent). Goodwin <i>et al</i>. (2011) discussed the synonymy of this species, and considered <i>Clathria</i> (<i>Dendrocia</i>) <i>tuberculata</i> (Burton) as a possible valid species, and recorded it from Malvinas (Falklands) Islands. We assigned our specimens to <i>C.</i> (<i>M.</i>) <i>antarctica</i> (Topsent), considering the synonymy proposed, and also, because “ <i>tuberculata</i> ” was recorded in shallower waters. Other encrusting specimens recorded by us and published in Schejter <i>et al</i>. (2011) were assigned to <i>C.</i> (<i>M.</i>) <i>antarctica</i> in the shelf break area of the Argentine Sea (at 38° 20.02'S 55° 30.22' W 106 m depth), although the present specimen has larger spicules. The larger toxas found in specimens presently dealt with those figured by Burton (1934) in his specimen of “ <i>Pseudanchinoe toxifera ”</i>.</p> <p> <i>......continued on the next page......continued on the next page</i></p>Published as part of <i>Barbara, Calcinai, 2017, Description of Antho (Plocamia) bremecae sp. nov. and checklist of Microcionidae (Demospongiae: Poecilosclerida) from Burdwood Bank and neighboring areas, SW Atlantic Ocean, pp. 580-594 in Zootaxa 4312 (3)</i> on pages 587-589, DOI: 10.11646/zootaxa.4312.3.11, <a href="http://zenodo.org/record/855645">http://zenodo.org/record/855645</a>
Clathria (Axosuberites) nidificata
No full text<i>Clathria</i> (<i>Axosuberites</i>) <i>nidificata</i> (Kirkpatrick, 1907) <p>Figure 4</p> <p> <b>Material examined.</b> Two specimens (MSNG N° 59506, MACN IN- 41004) collected at station 1 (54°29.07’ S; 62°10.76’ W) at 306 meters depth (labeled during the cruise as NBP 05/08 TB 1 #7). Collection date: April 2008. Collector: Laura Schejter.</p> <p> <b>Description.</b> Specimens are more or less globular, with digitiform, cylindrical outgrowths and about 4 cm long (Figure 4 A). The base is constricted, probably to stay attached to the substrate. The living specimens were light brown, and got slightly red when dried. Spicules are two categories of styles and toxas. The styles I (Figure 4 B) are larger, straight, smooth and thick, 1175–(1273±88)– 1400 x 40–(45±7)–50 µm, while the other category, styles II (Figure 4 C), are straight, curved or sinuous, and thinner, 560–(679±120)– 1120 x 7.5–(19±10)–30 µm. Toxas are variable in length 130–(365±179)–670 x 10 µm, with prominent and narrow central curve; smaller toxas are entirely smooth (Figure 4 D), while larger ones have spinulated tips (Figure 4 E, F).</p> <p> <b>Distribution and habit.</b> This species has been recorded from Antarctic waters and South Georgia Islands (Kirkpatrick,1908; Koltun 1964; Ríos <i>et al</i>. 2004). Burton (1940) also identified this species for Argentine waters off Mar del Plata and Miramar, from samples collected in 1925 and 1928; however, he did not provide images or measurements of the identified specimens. Since no other records were found in Argentina until present, this would be the third record of the species in Argentina, and also the first record for the Burdwood Bank area.</p> <p> <b>Remarks.</b> Desqueyroux (1975), Koltun (1976) and Hooper (1996) considered this species to possess a high morphological variability, and synonymized <i>Clathria</i> (<i>Axosuberites</i>) <i>nidificata</i> (Kirkpatrick), <i>C.</i> (<i>A.</i>) <i>flabellata</i> (Topsent), and <i>C.</i> (<i>A.</i>) <i>ramea</i> (Koltun). Other authors (Ríos <i>et al</i>. 2004; Campos <i>et al</i>. 2007) considered that at least <i>C.</i> (<i>A</i>.) <i>flabellata</i> and <i>C.</i> (<i>A.</i>) <i>nidificata</i> were different taxa. Pansini <i>et al.</i> (1994) tested by means of a morphometric spicular analysis the “laminar” (flabellate) and the “ramose” (ramea) morphotypes, arriving at a significant difference, although they concluded that a genetic analysis was needed to confirm a specific separation of these morphs. Ríos (2007) again considered <i>C. (A) flabellata</i> and <i>C. (A.) nidificata</i> as different species based on their general morphology, spicule categories and sizes. Subsequently, Van Soest <i>et al</i>. (2016) listed the three taxa as separated (and valid) species. In this regard, considering the description provided, the re-analysis of the holotype made by Hooper (1996), in which the toxas with the spined tips were found (overlooked in the original description), and that the species was also recorded in Argentina, we assigned the specimens described here to <i>C.</i> (<i>A</i>.) <i>nidificata</i>. Compared to our specimens, the Antarctic ones described by Ríos (2007) are slightly different regarding the general morphology, despite the fact that our specimens are also smaller, and had smaller spicule sizes in general, with no spinulation in the toxas I. On the other hand, the Antarctic specimens described by Campos <i>et al</i>. (2007) as <i>C. (A) nidificata</i> presented a more similar morphology, having also spinulated toxas I and similar spicule sizes. In this case, however, styles of the Antarctic specimens reached bigger sizes than in Burdwood bank specimens. In this sense, <i>C. (A.) nidificata</i> apparently may show a wide variety of body morphologies and spicule sizes that could be related to different habitats found from its recorded distributional range.</p>Published as part of <i>Barbara, Calcinai, 2017, Description of Antho (Plocamia) bremecae sp. nov. and checklist of Microcionidae (Demospongiae: Poecilosclerida) from Burdwood Bank and neighboring areas, SW Atlantic Ocean, pp. 580-594 in Zootaxa 4312 (3)</i> on pages 586-587, DOI: 10.11646/zootaxa.4312.3.11, <a href="http://zenodo.org/record/855645">http://zenodo.org/record/855645</a>
FIGURE 6. Chondropsis subtilis n in Sponges associated with octocorals in the Indo-Pacific, with the description of four new species
No full textFIGURE 6. Chondropsis subtilis n. sp. A–B, Living sponge encrusting Carijoa riisei in situ. Note in B the pink massive sponge close to C. riisei might be the holotype of this species; C, Holotype encrusting several branches of C. riisei; D, Sand and spicules creating a fine and regular network on the sponge surface; E, Sponge surface showing a homogeneous layer of sand, foreign spicules and strongyles; F, Choanosomal skeleton of ascending tracts of spongin, embedded with sand grains, strongyles and foreign spicules; G, Straight and very thin strongyle; H, Very thin sigmas.Published as part of Calcinai, Barbara, Bavestrello, Giorgio, Bertolino, Marco, Pica, Daniela, Wagner, Daniel & Cerrano, Carlo, 2013, Sponges associated with octocorals in the Indo-Pacific, with the description of four new species, pp. 1-61 in Zootaxa 3617 (1) on page 13, DOI: 10.11646/zootaxa.3617.1.1, http://zenodo.org/record/24815
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Stability of the sponge assemblage of Mediterranean coralligenous concretions along a millennial time span
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