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FIGURE 8 in Description of two new deepwater species of the genus Brookula Iredale, 1912 (Mollusca, Gastropoda, Trochoidea), with a revision of the genus for the Subantarctic and Arctic Sector of the Atlantic Ocean *
No full textFIGURE 8: The geographic distribution of Brookula bohni sp. nov. with a 2500 m depth contour in light grey.Published as part of Schwabe, Enrico & Engl, Winfried, 2008, Description of two new deepwater species of the genus Brookula Iredale, 1912 (Mollusca, Gastropoda, Trochoidea), with a revision of the genus for the Subantarctic and Arctic Sector of the Atlantic Ocean *, pp. 187-204 in Zootaxa 1866 on page 198, DOI: 10.5281/zenodo.18370
Brookula argentina Zelaya, Absalao & Pimenta 2006
No full text<i>Brookula argentina</i> (Zelaya, Absalão & Pimenta, 2006) <p>(Figs 1–2)</p> <p> <i>Benthobrookula argentina</i> Zelaya, Absalão & Pimenta, 2006: 79 –80, fig. 4.</p> <p> <b>Holotype</b> (MLP: 11977), not examined, SEM images available in Zelaya <i>et al.</i> (2006). <i>Type locality</i>: Atlantic Ocean, South Georgia (54°18’S 35°30’W), 94 m (OD).</p> <p> <i>Material examined:</i> Five specimens (ZSM Mol 20070902) from Antarctica, Bransfield Strait, St. PS 56/ 174–01 (63°01.10’S 61°09.10’W to 63°01.30’S 61°08.60’W), 311–365 m, collected during the ANT XVII/3 (EASIZ III) expedition. One specimen (ZSM Mol 20020184) from Antarctica, Bransfield Strait, St. PS 56/ 149–01 (62°30.00’S 56°55.80’W to 62°30.10’S 56°56.10’W), 909–911 m, collected during the ANT XVII/3 (EASIZ III) expedition, leg. Michael Schrödl.</p> <p> <i>Remarks</i>: The new material considerably extends the geographic and bathymetric range of this species that formerly was known from its type locality only (Fig. 2).</p>Published as part of <i>Schwabe, Enrico & Engl, Winfried, 2008, Description of two new deepwater species of the genus Brookula Iredale, 1912 (Mollusca, Gastropoda, Trochoidea), with a revision of the genus for the Subantarctic and Arctic Sector of the Atlantic Ocean *, pp. 187-204 in Zootaxa 1866</i> on pages 190-191, DOI: <a href="http://zenodo.org/record/183706">10.5281/zenodo.183706</a>
Brookula Iredale 1912
No full text<i>Brookula</i> Iredale, 1912 <p> <i>Type species</i>: <i>Brookula stibarochila</i> Iredale, 1912, OD.</p> <p> <i>Distribution</i>: Mainly in the oceans of the southern hemisphere, northern hemisphere records from the Indian and Pacific Oceans only. Shallow water to abyssal depth (Gage & Taylor 1991). Miocene to Recent (Finlay 1924).</p> <p> <i>Diagnosis</i>: Shell 1.2–2.5 mm, trochoid globose, thin, orthostrophic, paucispiral, dextral, with up to 4 rounded whorls. Periostracum absent. Umbilicus ranges from closed to widely open. Protoconch with smooth or anastomosing ribbed sculpture, up to 400 µm in diameter. Shell sculpture consists of axial ribs; spiral sculpture well defined, but weaker, sometimes overriding and forming beads at intersections with axial ribs; fine growth lines present. Suture deeply constricted. Aperture rounded, with a slightly thickened lip and complete peritreme, nacreous layer absent. Operculum circular, multispiral, with central nucleus.</p> <p>Radula rhipidoglossate, formula 5­2­1­2­5; rhachidian stout, higher than wide, with cusped edge well serrated. Outer lateral and marginal teeth similar, except for smaller cusps in the latter.</p> <p>Cephalic tentacles with a dense fringe of sensory papillae at the distal end; foot anterior with two wide, posterior with two shorter lappets, laterally with short, elongate epipodial tentacles without epipodial sensory organs but a fringe of slender hair­like cilia.</p>Published as part of <i>Schwabe, Enrico & Engl, Winfried, 2008, Description of two new deepwater species of the genus Brookula Iredale, 1912 (Mollusca, Gastropoda, Trochoidea), with a revision of the genus for the Subantarctic and Arctic Sector of the Atlantic Ocean *, pp. 187-204 in Zootaxa 1866</i> on pages 189-190, DOI: <a href="http://zenodo.org/record/183706">10.5281/zenodo.183706</a>
Brookula bohni Schwabe & Engl, 2008, sp. nov.
No full textBrookula bohni sp. nov. (Figs 7–8) Type material Holotype (ZSM Mol 20070895), leg. Katrin Linse, February 4 2002, ANT XIX/ 3 (ANDEEP I). Paratypes, one from type locality (ZSM Mol 20021185). Two paratypes (ZSM Mol 20021177) Antarctica, Drake Passage, St. PS 61 / 042–02 (59 ° 40.29 ’S 57 ° 35.43 ’W to 59 ° 40.42 ’S 57 ° 35.27 ’W), 3680–3683 m, Katrin Linse, January 27 2002, ANT XIX/ 3 (ANDEEP I). Besides the SEMmounted holotype, all other specimens are fixed and preserved in 96 % ethanol. Type locality: Antarctica, South Shetlands, St. PS 61 /043–08 (60 ° 27.12 ’S 56 °05.10’W to 60 ° 27.18 ’S 56 °04.80’W), 3959–3961 m (Fig. 8). Etymology: The species is named after our friend Jens Michael Bohn (ZSM), a holothurian specialist and participant of the relevant expeditions. We selected his surname because his nickname is “ Bohni ”. Description: Shell minute, up to 1.30 mm long, 1.28 mm wide (Fig. 7 A), globosely turbinate, fragile, translucent white in color, with inflated whorls slightly depressed at the shoulder, slightly expanded laterally, low spired, spire angle ranging from 80 ° (smallest paratype) to 85 ° (holotype). Protoconch (Fig. 7 D) of 1.25 whorls, 280 µm in diameter, 100 µm high, globose, sculptured with fine anastomosing threads, forming microscopic pits of irregular arrangment. Teleoconch (Figs 7 A, C) of up to 2.75 whorls with convex profile. Suture incised. Last adult whorl globose, slightly depressed at shoulder. Aperture oval, peritreme holostomate, although very weak at periphery of preceeding whorl; with thick inner, thin outer lip. Shell base roundly inflated. Umbilicus (Fig. 7 B) tightly open, circular, deep. Axial sculpture of narrow ribs, ranging from 29 (largest paratype) to 31 on last whorl in holotype, 25 on penultimate whorl. Ribs regularly spaced, rounded, low, interspaces about three times rib width. Spiral sculpture of numerous flat threads, seven on first teleoconch whorl, about 12 on last adult whorl, narrower than axial ribs, crowded in upper and lower half of whorl, centrally absent (in the two small paratypes) or interrupted by distinctly separated slightly higher spirals, not overlaying the axial ribs distally. Nine flat spirals, two spiral cords (with inner being largest), which surround umbilicus, at shell base. Operculum circular, multispiral, with centric nucleus. Comparisons: Brookula spinulata Absalão, Miyaji & Pimenta, 2001 differs in 1) its coarse sculpture with spinulate projections at the axial ribs, 2) the presence of fine axial lines between the spiral threads, 3) the lower number (6 vs 12) of spirals on the last body whorl, despite the general larger size, 4) the lower number (20 vs 29–31) of axial ribs. Brookula calypso (Melvill & Standen, 1912) differs in 1) having cancellate sculpture, built up by regularly arranged axial ribs and spiral threads, 2) the presence of small axial threads between the axial ribs, 3) having a slightly larger protoconch (295 vs 280 µm) although it has only one whorl, 4) having a larger spire angle (90 vs 85 °), 5) having a shallow suture. Brookula powelli Clarke, 1961 differs in 1) shell proportions (0.81–0.93 vs 0.91–1.11, SL/SW ratio), 2) the lesser acute spire angle (min. 93.5 vs max. 85 °), 3) the wider umbilicus (440 vs 135 µm), 4) the larger protoconch (one whorl of c. 350 µm vs 1.25 whorl of 280 µm), 5) the higher number of axial ribs at last whorl (37 vs 29–31), 6) the round vs oval aperture. The oval aperture and the characteristic sculpture make the species easily separable from the remaining Antarctic congeners.Published as part of Schwabe, Enrico & Engl, Winfried, 2008, Description of two new deepwater species of the genus Brookula Iredale, 1912 (Mollusca, Gastropoda, Trochoidea), with a revision of the genus for the Subantarctic and Arctic Sector of the Atlantic Ocean *, pp. 187-204 in Zootaxa 1866 on pages 196-198, DOI: 10.5281/zenodo.18370
Brookula exquisita Clarke 1961
No full textBrookula exquisita Clarke, 1961 (Figs 3 –4) Brookula (Benthobrookula) exquisita Clarke 1961: 356 –357, pl. 3, fig. 8, pl. 4, fig. 2. Holotype (MCZ: 225964), not examined, SEM images available in Absalão et al. (2001) and Zelaya et al. (2006). Type locality: Antarctica, South Georgia (55 ° 29 ’S 37 ° 57 ’W), 3758 m. OD. Material examined: Four specimens (ZSM Mol 2007089220070894), Antarctica, South Sandwich Islands, St. PS 61 / 140 –08 (58 ° 15.98 ’S 24 ° 53.72 ’W to 58 ° 16.13 ’S 24 ° 53.87 ’W), 2947–2970 m, leg. Michael Schrödl, March 22 2002, ANT XIX/ 4 (ANDEEP II) expedition. One specimen fixed and preserved in 75 % ethanol (ZSM Mol 20070892); remainder dry shells only including SEMmounted specimen (ZSM Mol 20070894). One specimen (ZSM Mol 20021582), Antarctica, South Sandwich Islands, St. PS 61 / 140 –07 (58 °16.00’S 24 ° 53.78 ’W to 58 ° 16.39 ’S 24 ° 54.85 ’W), 2941–2945 m, leg. Michael Schrödl, March 21 2002, ANT XIX/ 4 (ANDEEP II) expedition, fixed and preserved in 96 % ethanol. One dry specimen (ZSM Mol 20070901), Antarctica, Northwest Weddell Sea, St. PS 61 / 131 –03 (65 ° 19.19 ’S 51 ° 32.54 ’W to 65 ° 19.99 ’S 51 ° 31.23 ’W), 3050–3055 m, leg. Michael Schrödl, March 5 2002, ANT XIX/ 4 (ANDEEP II) expedition. Five specimens (ZSM Mol 20021216; 20021170), Antarctica, Drake Passage, St. PS 61 / 041–03 (59 ° 22.24 ’S 60 °04.06’W to 59 ° 22.55 ’S 60 °04.01’W), 2359–2375 m, leg. Katrin Linse, January 26–27 2002, ANT XIX/ 3 (ANDEEP I) expedition, fixed and preserved in 96 % ethanol. Description of a specimen examined by SEM (ZSM Mol 20070894) Shell minute, 1.11 mm long, 1.67 mm wide (Fig. 3 A), SL/SW ratio 0.66, depressed, fragile, white in color, with roundly inflated whorls, clearly expanded laterally, low spired, spire angle 126 °. Protoconch (Fig. 3 D) of one whorl, 320 µm in diameter, 116 µm long, globose, sculptured with fine anastomosing threads, forming reticulate pattern. Teleoconch (Figs 3 A, C) of up to 1.75 whorls with convex profile. Whorls connected only for a short distance, more or less at periphery of preceding one. Suture consequently deep and channeled. Last whorl clearly increasing in diameter and laterally expanded. Aperture circular, 0.68 mm high (SL/AL ratio 1.63), peritreme holostomate, with thin lip. Shell base roundly inflated. Umbilicus (Fig. 3 B) phaneromphalous, circular, wide, surrounded by four slightly elevated spiral cords, two of them entering umbilicus. Shell surface cancellate. Axial sculpture of narrow ribs, 29 on last whorl in the holotype, deeply entering the umbilicus. Ribs regularly spaced, rounded, interspaces about four times rib width. Spiral sculpture of numerous flat threads, five on first teleoconch whorl, about 14 on the last adult whorl, distinctly narrower than axial ribs, partly overlaying axil ribs. Operculum circular, multispiral, with centric nucleus. Remarks: This is the first record of this species from outside the type locality and the new material considerably extends the geographic and bathymetric range of this species (Fig. 4). There are minor differences to the description of the holotype presented by Zelaya et al. (2006). Although somewhat smaller (1.11 mm vs 1.5 mm) our specimen has a slightly larger protoconch (320 µm vs 300 µm). The spire angle in our specimen is greater (126 ° vs 105 °) and although the teleoconch whorl number is smaller (1.75 vs 2.25), the number of axial ribs on the last body whorl is similar (29 vs 28). However, too little is known about the intraspecific variation of this species to warrant the description of a new species on these differences alone. Figure 4: The geographic distribution of Brookula exquisita Clarke, 1961. The circle marks the literature data (type locality only), while the triangles show the new records. A 2500 m depth contour in light grey.Published as part of Schwabe, Enrico & Engl, Winfried, 2008, Description of two new deepwater species of the genus Brookula Iredale, 1912 (Mollusca, Gastropoda, Trochoidea), with a revision of the genus for the Subantarctic and Arctic Sector of the Atlantic Ocean *, pp. 187-204 in Zootaxa 1866 on pages 191-193, DOI: 10.5281/zenodo.18370
Brookula charleenae Schwabe & Engl, 2008, sp. nov.
No full text<i>Brookula charleenae</i> sp. nov. <p>(Figs 5–6)</p> <p> <i>Type material</i></p> <p> <b>Holotype</b> (ZSM Mol 20070879), leg. Michael Schrödl, March 22 2002, during the ANT XIX/4 (ANDEEP II) expedition.</p> <p> Two <b>paratypes</b> (ZSM Mol 20070880) from type locality, all specimens were fixed and preserved in 75% ethanol except for the SEM­mounted holotype.</p> <p> <i>Type locality</i>: Antarctica, South Sandwich Islands, St. PS 61/140–08 (58°15.98’S 24°53.72’W to 58°16.13’S 24°53.87’W), 2947–2970 m (Fig. 6).</p> <p> <i>Etymology</i>: The species is named after the first author’s daughter Charleen Schwabe.</p> <p> <i>Description:</i> Shell minute, reaching 1.42 mm long and 1.25 mm wide (Fig. 5A), globosely turbinate, fragile, white in color, with roundly inflated whorls, slightly expanded laterally, low spired, spire angle ranges from 70° (holotype) to 81° (larger paratype). Protoconch (Figs 5C, D) of 1.5 whorls, 278 µm in diameter, 220 µm high, globose, sculptured with fine anastomosing threads, forming reticulate pattern. Teleoconch (Fig. 5A) of up to 2.75 whorls with convex profile. Suture deeply constricted. Last adult whorl globose, slightly expanded laterally. Aperture circular, peritreme holostomate, with thin lip. Shell base roundly inflated. Umbilicus (Fig. 5B) narrow, circular, deep. Axial sculpture of narrow ribs, 28 on last whorl in the holotype, 27 on the penultimate whorl, deeply entering the umbilicus. Ribs regularly spaced, rounded, nearly lamellous, interspaces between them about three times rib width. Spiral sculpture of numerous flat threads, twelve on first teleoconch whorl, about 42 on last adult whorl, narrower than axial ribs, partly double­spaced, not overlaying axil ribs distally. Operculum circular, multispiral, with centric nucleus.</p> <p> <i>Comparisons</i>: <i>Brookula pfefferi</i> Powell, 1951: despite nearly the same shell proportions, the new species can be easily separated from <i>B. pfefferi</i> by 1) the absence of spiral cords on the shell base, 2) the higher number of spiral threads on the last adult whorl (42 vs 20–26), 3) the smaller protoconch (278 vs 330–400 µm). <i>Brookula strebeli</i> Powell, 1951: this species has nearly the same size but has 1) a higher SL/SW ratio (1.20 vs 1.14), 2) a larger protoconch (300 vs 278 µm), 3) by nearly the same teleoconch whorl number (2 vs 2.75) a lower number of axial ribs (20 vs 28), 4) a much lower number of spiral threads (14 vs 42), 5) a nearly­closed umbilicus, 6) three to four spiral cords on the shell base.</p> <p> <i>Brookula calypso</i> (Melvill & Standen, 1912): in contrast to the new species this species has 1) a higher spire angle (90 vs 81°), 2) a larger sized protoconch (295 vs 275 µm) with only one whorl vs 1.5 whorls, 3) only 14–17 vs 28 spiral ribs on the last whorl, 4) two vs no spiral cords around the umbilicus.</p> <p> <i>Brookula conica</i> (Watson, 1886): the only other South Atlantic deep water species that does not have spiral cords around the umbilicus differs in 1) its larger size (up to 1.8 vs 1.42 mm), 2) the wider umbilicus (130 vs 105 µm [data from Absalão <i>et al.</i> 2001, fig. 2 b]), 3) the lower number of the wider spaced axial ribs (19 vs 28), 4) having very fine axial lines between the spiral threads, 5) its much smaller protoconch (145 vs 278 µm [data from Absalão <i>et al.</i> 2001, figs 2 f, d]).</p> <p>Scale bars: A 500 µm, B, C 100 µm, D 10 µm.</p> <p> <i>Brookula paranaensis</i> (Zelaya, Absalão & Pimenta, 2006): this species differs from the new species in having 1) different shell proportions (compare table in original description), 2) a similar sized protoconch (270 vs 278 µm) with only one whorl, 3) a larger spire angle, 4) a higher number (42 vs 28) of closer set axial ribs, 5) a smaller number of spiral threads on last adult whorl (20–21 vs 42), 6) three to four vs no spiral cords around the umbilicus.</p> <p> <i>Brookula kerguelensis</i> Thiele, 1925 is the most similar species. It differs, however, in 1) its larger size (1.6 x 1.35 mm with the same whorl number), 2) the lower spire angle (c. 68°, taken from the illustration), 3) the smaller number of less closely set and flatter axial ribs on the penultimate whorl (c. 20 vs 27) on last whorl, 4) having an oval aperture. This species is known from a single slightly worn specimen (holotype, ZMB/Moll­ 64050) from the Kerguelen Islands (49°S 70°44’E) only.</p> <p>None of the comparable congeners was ever reported from such depths.</p>Published as part of <i>Schwabe, Enrico & Engl, Winfried, 2008, Description of two new deepwater species of the genus Brookula Iredale, 1912 (Mollusca, Gastropoda, Trochoidea), with a revision of the genus for the Subantarctic and Arctic Sector of the Atlantic Ocean *, pp. 187-204 in Zootaxa 1866</i> on pages 194-195, DOI: <a href="http://zenodo.org/record/183706">10.5281/zenodo.183706</a>
Brookula pfefferi Powell 1951
No full textBrookula pfefferi Powell, 1951 (Fig. 9) ? Cyclostrema decussatum Pelseneer, 1903: 19, pl. 5, fig. 48. Brookula pfefferi Powell, 1951: 104, pl. 5, fig. 8. Brookula rossiana Dell, 1990: 102, fig. 169. Brookula sinusbreidensis Numanami & Okutani, 1991: 38, figs 2–6. Brookula delli Numanami, 1996: 55, figs 30 A–E. Holotype of B. pfefferi (NHM 1961.368). Type locality: Atlantic Ocean, South Georgia, off mouth of Stromness Harbour (54 °04’S 36 ° 27 ’W – 53 ° 58 ’S 36 ° 26 ’W), 155– 178 m. OD. Material examined: 40 specimens (ZSM Mol 20021687), Weddell Sea sector of the Antarctic Peninsula (63 °01.10’S 61 °09.10’W), 311–365 m, ANT XVII/ 3 (EASIZ 3). Remarks: This is the only species for which numerous specimens were available. The shell morphology of B. pfefferi is sufficiently described in Absalão et al. (2001) and Zelaya et al. (2006) but at least a first preliminary (excluding the ctenidia) overview of the external bauplan of the species may be given here (Fig. 9). Radula data were provided by Zelaya et al. (2006). A detailed histological examination is being undertaken by Thomas Kunze (LudwigMaximilians University, Munich, Germany). The cylindrical head has a cloven, obtusely pointed snout. There is a pair of long, thick cephalic tentacles that show in their anterior half laterally dense fringes of sensory papillae. It is likely that the short rudiment on the base of the cephalic tentacle (Fig. 9 C) belongs to the eye stalk (eyes are not visble in the examined specimen), but this has to be confirmed by the histological data. The foot is fleshy and elongate, anteriorly with two wide, conical foot lappets and posteriorly, under the horny, circular, multispiral operculum (Fig. 9 D) with two shorter ones. Laterally between the anterior and posterior foot lappets a fringe of about 12 short, smooth, elongate epipodial tentacles is situated; at least on the dried animal, the tentacles do not show epipodial sense organs. There is a dense fringe of slender, hairlike cilia on the lateral foot margins. Immediately behind the right cephalic tentacle (Figs 9 A, C, E; marked with “*”) we detected a structure, which could be a penis, but also requires confirmation by histology. Examination of the shell by SEM showed that the the inner shell layer of the aperture does not consist of a prismatic nacreous layer as typical for iridescence (see Fuchigami & Sasaki 2005). Absalão et al. (2001) failed in locate the holotype of Cyclostrema decussatum Pelseneer, 1903, and Zelaya et al. (2006) did not take that species into account. The holotype of this species should be together with the other Pelseneer types in the Institut Royal des Sciences Naturelles de Belgique, Bruxelles, Belgium, but according to Yves Terryn (Scientific Associate), who searched the collection for it on the authors request, the type is not to be found. Based on the species’ original descriptions and figures we can not see differences between Brookula decussata (Pelseneer, 1903) and B. pfefferi Powell, 1951, and consider the latter merely a junior synonym of the former. It is important to point out that Brookula decussata (Pelseneer, 1903) does not “clearly differ from Benthobrookula pfefferi in having a smaller shell, with fewer, more separated, spiral threads” (Zelaya et al. 2006, p. 80) but is instead really similar (see also Powell 1951, p. 104). A direct comparision of Pelseneer’s illustration (1903, pl. 5, fig. 48) with the photo of the holotype of Brookula pfefferi Powell, 1951, available from Zelaya et al. (2006, fig. 5 A), does not only show the close similarity but also give the impression that the spiral threads are not “more separated”. In addition, while Zelaya et al. (2006) gave a maximum size of 1.83 mm for Brookula pfefferi Powell, 1951 (2 mm in the original description!), the maximum shell size for B. decussata (Pelseneer, 1903) is originally given as 2.5 mm and can thus under no circumstances be defined as “smaller”.Published as part of Schwabe, Enrico & Engl, Winfried, 2008, Description of two new deepwater species of the genus Brookula Iredale, 1912 (Mollusca, Gastropoda, Trochoidea), with a revision of the genus for the Subantarctic and Arctic Sector of the Atlantic Ocean *, pp. 187-204 in Zootaxa 1866 on page 199, DOI: 10.5281/zenodo.18370
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
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