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Redescription of Admete sadko Gorbunov, 1946 (Gastropoda: Cancellariidae)
No full textNekhaev, Ivan O. (2018): Redescription of Admete sadko Gorbunov, 1946 (Gastropoda: Cancellariidae). Zootaxa 4508 (3): 427-430, DOI: 10.11646/zootaxa.4508.3.
A new species of Menestho Møller, 1842 from the Arctic with remarks on Menestho albula (Fabricius, 1780) (Gastropoda: Heterobranchia: Pyramidellidae)
No full textNekhaev, Ivan O. (2017): A new species of Menestho Møller, 1842 from the Arctic with remarks on Menestho albula (Fabricius, 1780) (Gastropoda: Heterobranchia: Pyramidellidae). Zootaxa 4347 (1), DOI: https://doi.org/10.11646/zootaxa.4347.1.1
Redescription of Leptogyra bujnitzkii (Gorbunov, 1946) comb. nov., the first representative of the gastropod subclass Neomphaliones from the high Arctic
No full textKrol, Ekaterina N., Nekhaev, Ivan O. (2020): Redescription of Leptogyra bujnitzkii (Gorbunov, 1946) comb. nov., the first representative of the gastropod subclass Neomphaliones from the high Arctic. Zootaxa 4759 (3): 446-450, DOI: 10.11646/zootaxa.4759.3.1
FIGURE 1 in Morphology and systematic position of Cingula tumidula G. O. Sars, 1878 (Gastropoda: Rissoidae)
No full textFIGURE 1. Shells of Pusillina tumidula. A. Barents Sea, Dalne-Zelenetskaya Bay, 59 m, 69°07.92'N, 36°05.45'E, MMBI, no number; B. Barents Sea, Malaya Sharkovka Bay, 27 m, 69°12.57'N, 34°54.31'E, MMBI, no number; C. Eastern Barents Sea (Pechora Sea), 17.5 m, 69°15.61'N, 57°22.76'E, MMBI, no number; D, E. Holotype of Cingula tumidula, ZMO D659; E. after Sars (1878); F. specimen from the type sample of Punctulum minutuim labeled as "paratype", ZIN 35667/2; G. Lectotype of Rissoa griegi, ZMB 20857; H. Holotype of Punctulum minutum, ZIN 35666/1. Scale = 1 mm.Published as part of Nekhaev, Ivan O., 2016, Morphology and systematic position of Cingula tumidula G. O. Sars, 1878 (Gastropoda: Rissoidae), pp. 395-400 in Zootaxa 4184 (2) on page 396, DOI: 10.11646/zootaxa.4184.2.13, http://zenodo.org/record/16480
Leptogyra Bush 1897
No full text<p> <b> Genus <i>Leptogyra</i> Bush, 1897</b> (<i>Leptogyra</i> Bush, 1897: 135–136)</p> <p> <b>Type species.</b> <i>Leptogyra verrilli</i> <b>Bush, 1897</b></p>Published as part of <i>Krol, Ekaterina N. & Nekhaev, Ivan O., 2020, Redescription of Leptogyra bujnitzkii (Gorbunov, 1946) comb. nov., the first representative of the gastropod subclass Neomphaliones from the high Arctic, pp. 446-450 in Zootaxa 4759 (3)</i> on page 446, DOI: 10.11646/zootaxa.4759.3.13, <a href="http://zenodo.org/record/3741156">http://zenodo.org/record/3741156</a>
Menestho schikovi Nekhaev 2017, sp. n.
No full textMenestho schikovi Nekhaev sp. n. Menestho truncatula: Kantor & Sysoev 2006: 243 fig. 122С (partly), non Odhner, 1915. Type material. holotype (empty shell) (Figs 1A, 2 A, I), 3.12.2015, van Veen grab, ZIN 62135 /1, 6 paratypes (empty shells) from the same sample ZIN 62136 /2 and 2 paratypes (empty shells) from the same sample LMBI IN- 3. Type locality. Svalbard, Spitsbergen Island, Billefjorden, R / V Dalnie Zelentsy, sta. 44, 78°39.6'N, 16°40.4'E, 188 m. Other examined material: 3 spms, 2 shells, Kara Sea, 76°41'N, 88°14'E, 45 m, R/V G. Sedov, leg. Vagin, 0 6.09.1934, ZIN 22732 (studied with SEM); 4 spms, Kara Sea, 75°40'N, 80°26'E, 42 m, R/V G. Sedov, leg. Vagin, 0 9.09.1934, ZIN 35691; 3 spms, Kara Sea, 76°17'N, 75°08'E, 75 m, R/V G. Sedov, leg. Vagin, 21.09.1934, ZIN 35693; 1 spm, Severnaya Zemlya, 80°30'N, 90°03’E, 174 m, R/V Fyodor Litke, 29.09.1948, ZIN 35701; 1 spm,Laptev Sea, 77°25'N, 115°48'E, 62 m, R/V Sadko, leg. G.P. Gorbunov, 16.08.1937, ZIN 35696; 2 spms, Laptev Sea, 76°36'N, 118°30'E, 51 m, R/V Sadko, leg. G.P. Gorbunov, 0 2.10.1937, ZIN 35697; 1 spm, 71°24'78''N, 174°22'03''E, 585 m, R/V Professor Chromov, 22.08.2004, ZIN 60879. Diagnosis: Menestho with conical shell, convex, evenly rounded whorls, open umbilicus and straight growth-lines. Description: Shell small, conical, white or yellowish with convex, evenly rounded whorls divided by deep suture (Figs. 1 A, C, E, 2A). Shell surface with fine, frequent (8–11 on body whorl), spiral ribs, almost semicircular in section, divided by very narrow interspaces (Fig. 2I). Axial sculpture, except for straight growth-lines (Fig. 2A, I) absent. Embryonic shell intorted, of type B, partially eroded on studied specimens, smooth or with very low pattern of spiral sculpture (Fig. 2G). Aperture oval with acute angle in upper part, no teeth or folds on columella. Umbilicus clearly visible, narrow. Operculum transparent, without peg (Fig. 2E). Measurements of holotype: shell height = 3.6 mm, aperture height = 1.2 mm, last whorl height = 2.3 mm, shell width = 2.0 mm, aperture width = 1.0 mm. Variability. Studied shells differ in width/height proportions (Fig 1 A, C, E), no other significant variability had been found. Distribution. Known from the Svalbard, the Kara and the Laptev seas. Single young specimen (ZIN 60879) with shell height = 2.5 mm corresponded to Menestho schikovi was found from the Chukchi Sea. Depth range 42– 585 m. Probably, the species lives in all seas of the Eurasian Arctic. Habitat. The species had been collected from silt substrates. The observed near-bottom temperature and salinity at the type locality were -1.4°C and 34.8 psu respectively. Menestho schikovi probably have a parasitic mode of life, like other pyramidellid species. However its host is unknown. Derivation of name. The species is named after Dr. Evgenij Schikov, enthusiastic malacologist and ecologist. Remarks. Shell of Menestho truncatula (Figs. 1D, 2B) (see also Odhner (1915) for the figures of syntypes) is wider than M. schikovi, upper part of its last whorl with flattened shoulder, not rounded. The aperture height in M. truncatula is about a half of shell height. In addition, M. truncatula have a reticulate pattern on the protoconch (Fig. 2F). Menestho albula differs from M. schikovi by prosocline growth-lines and absence of an umbilicus. Usually Menestho albula have coarser spiral sculpture and more flattened whorls. Menestho schikovi very resembles Menestho albula, which was described from West Greenland. However, type material of Turbo albulus had not been found neither during previous studies nor during my own examination of the collections of the Natural History Museum of Denmark, where the collections by Otto Fabricius are stored (Nekhaev et al. 2015). Hence, current knowledge on taxonomic status of Menestho albula is mainly based on topotypic samples collected by H.P.C. Møller (Warén 1991). A single shell from ZIN corresponds with the original description of Turbo albulus in shell shape, size and sculpture as well as with specimens from Iceland studied by Warén (1991) and specimens from the Murman Coast studied in this work. All mollusks have small (3.5 mm in height and lesser) conical, white, shell with flattened whorls (Fig. 1B, 2C–D). The reported size of 9 mm for Menestho albula (e.g. Rosenberg 2009) seems to be a result of confusion with another species. Spiral ribs of Menestho albula are usually of the same width with interspaces (Fig. 2 J–K). Some of the studied specimens from the Murman Coast have a «bend» on the suture (Fig. 2J) whereas others have not. The bend also has not been found in the topotypic specimen (Fig. 2K) and on a shell from Iceland depicted by Warén (1991: Fig. 27F), and hence, with limited knowledge available to date, I suggest that it is an intraspecific variation. All specimens had clearly prosocline growth-lines (Fig. 2 C–D, J–K). The umbilicus of Menestho albula is closed, its embryonic shell is smooth (Fig. 2H). Menestho albula have an Atlantic distribution: the species is known in the waters around Greenland, North of Iceland, Svalbard and SW Barents Sea (Warén 1991; Nekhaev 2014). Examination of the museum collection revealed that Menestho schikovi had been usually confused with Menestho truncatula. A specimen of the former species was also mistakenly depicted by Kantor & Sysoev (2006) as Menestho truncatula. Examination of museum collections showed that both species occur sympatrically in the Arctic. However, Menestho schikovi had not been found in the Barents and White seas yet. Menestho truncatula seems to be the most common representative of the family in the Arctic and has been found with certainty from Svalbard, all parts of the Barents Sea, the Kara, White, Laptev and East-Siberian Seas (Golikov 1987; Golikov et al. 2001; Nekhaev 2014; Nekhaev & Krol 2017).Published as part of Nekhaev, Ivan O., 2017, A new species of Menestho Møller, 1842 from the Arctic with remarks on Menestho albula (Fabricius, 1780) (Gastropoda: Heterobranchia: Pyramidellidae) in Zootaxa 4347 (1), DOI: 10.11646/zootaxa.4347.1.13, http://zenodo.org/record/104482
Admete sadko Gorbunov 1946
No full text<i>Admete sadko</i> Gorbunov, 1946 <p> <i>Admete sadko</i> Gorbunov 1946b: 310, 319, Plate I, fig 5.</p> <p> <b>Type material:</b> 1 syntype (empty shell), Laptev Sea, 76°12.9’N, 133°50’E, 47 m, R/ V Sadko, 21.08.1937, sta. 21, gray silt with sand (Fig. 1), ZIN 1 /61903. Gorbunov (1946b) also reported one more sample with two syntypes. The sample, however, has not been found during careful examination of ZIN collection and is apparently lost.</p> <p> <b>Type locality:</b> Laptev Sea, 76°12.9’N, 33°50’E, 47 m and 75°22’N, 135°00’E, 40 m.</p> <p> <b>Other material:</b> 1 living specimen and 1 empty shell, Kara Sea, 75°45’N, 86°05’E, 29 m, R/V Sadko, 20.08.1936, sta. 3, silt, ZIN 3/ 53455; 1 living specimen, Laptev Sea, 76°09’N, 120°00’E, 64 m, R/ V Sadko, 7.10.1937, sta. 77, ZIN 2 / 62429.</p> <p> <b>Redescription.</b> Shell of medium size for genus (Table 1), fusiform, fragile (Fig. 1, 2 A–B). Periostracum not marked. Whorls shouldered divided by deep suture. Spiral sculpture consists of prominent cords separarted by spaces of relatively equal size. Body whorl has up to 10 cords: 2—on shoulder of whorl 3–4 on periphery and 2–4 lesser developed cords on base of shell. Surface of cords often covered with secondary spiral riblets. Usually shoulder cords have weak wavy protrusions. Axial sculpture consists only of approximately straight growthlines. Early whorls eroded on all specimens, protoconch unknown. Aperture broad oval, large, its height is about 0.5 of total shell height. Siphonal canal short, slightly bended to the left. Outer lip rounded, corrugated reflecting spiral sculpture. Usually 2 weak collumelar folds present. Umbilicus closed. Operculum absent.</p> <p>AH—aperture height, AW—aperture width, LWH—last whorl height,</p> <p>PWH—penultimate whorl height, PWW—penultimate whorl width, SH—shell height, SW—shell width.</p> <p> Soft parts unknown (studied material contains only subadult living specimens). According to Gorbunov (1946b), radula in <i>Admete sadko</i> is absent.</p> <p> <b>Distribution.</b> <i>Admete sadko</i> is known from the Laptev and the Kara seas. Reports of the species from the Northern Atlantic (Petit & Harasewych 2005; Hemmen 2007) are erroneous.</p> <p> <b>Habitat.</b> Found on silty substrates, 29- 64 m.</p> <p> <b>Etymology.</b> The species is named after R/V Sadko, the ship from which the type samples were collected. Sadko (masculine, singular) is a hero of a Russian folktale. The word “ <i>sadko</i> ” was used as a noun in apposition.</p> <p> <b>Remarks.</b> Despite the very characteristic shell of <i>Admete sadko</i>, the species had not been recognized since its first description. This is likely due to the unclear first diagnosis and original figures that inaccurately reflect the proportions of shells and sculpture of molluscs described by Gorbunov (1946b). The species is also not very common.</p> <p> Gorbunov (1946b) gives two accounts of <i>Admete sadko</i>: a description in Russian on page 310 and its English translation on p. 319. Both agree with each other, but the Russian description contained some details that were missing in the English diagnosis. The name <i>Admete sadko</i> is also mentioned in a checklist by Gorbunov 1946a, another paper from the same volume with an original description of the species (Gorbunov 1946b). This publication contains biogeographical and ecological summary of benthos from the Laptev and East Siberian seas, without any comments on species taxonomy and diagnostics, which does not constitute a species description according to article 13.1 of the International Code of the Zoological Nomenclature.</p> <p> <i>Admete sadko</i> can be recognized from all species of Cancellariidae living in the Arctic by its sculpture of heavy spiral cords (Fig. 2). The species has a broader shell than <i>A. viridula, A. clivicola</i> (Fig. 2G), <i>Admete contabulata</i> (Fig. 2E) and <i>Iphinopsis solida</i> (Fig. 2F). These three latter species are also considerably smaller than <i>Admete sadko</i>. <i>Admete sadko</i> also differs from <i>Iphinopsis inflata</i> by the absence of an umbilicus. <i>Admete solida</i> have a similar shell proportions but can be recognized by its low spiral sculpture and rounded whorls (Sysoev & Kantor, 2002; Kantor & Harasewych, 2003).</p>Published as part of <i>Nekhaev, Ivan O., 2018, Redescription of Admete sadko Gorbunov, 1946 (Gastropoda: Cancellariidae), pp. 427-430 in Zootaxa 4508 (3)</i> on pages 427-429, DOI: 10.11646/zootaxa.4508.3.5, <a href="http://zenodo.org/record/2607280">http://zenodo.org/record/2607280</a>
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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