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| Format: | Recurso digital |
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Zenodo
2022
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| Accès en ligne: | https://doi.org/10.5281/zenodo.7814340 |
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Table des matières:
- <p>VELUTININAE GRAY, 1840</p><p>(FIGS 2, 3, 4C–F, 6C, D, 9B, 10B, C, 11B, C, N, O)</p><p>Velutininae Gray, 1840: 90;</p><p>type genus <i>Velutina</i> J. Fleming, 1820.</p><p>Marseninidae Odhner, 1913: 9 [as Marsenininae];</p><p>type genus <i>Marsenina</i> Gray, 1850.</p><p>Sacculidae Thiele, 1929: 266;</p><p>type genus <i>Sacculus</i> Hirase, 1927 [permanently invalid, being the type genus a junior homonym of <i>Sacculus</i> Grosse, 1851 (Rotifera)].</p><p>Pseudosacculidae Kuroda, 1933: 186 [replacement name for Sacculidae Thiele];</p><p>type genus <i>Pseudosacculus</i> Hirase, 1928.</p><p>Capulacmaeidae Golikov & Gulbin, 1990: 108 [as Capulacmaeinae];</p><p>type genus <i>Capulacmaea</i> M. Sars, 1859.</p><p><i>Included genera:</i> <i>Cartilagovelutina</i> Golikov & Gulbin, 1990, <i>Ciliatovelutina</i> Golikov & Gulbin, 1990, <i>Cilifera</i> Golikov & Gulbin, 1990, <i>Limneria</i> H.Adams & A. Adams, 1851, <i>Marsenina</i> Gray, 1850, <i>Onchidiopsis</i> Bergh, 1853, <i>Piliscus</i> Lovén, 1859, <i>Pseudosacculus</i> Hirase, 1928, <i>Pseudotorellia</i> Warén, 1989, <i>Torellivelutina</i> J. H. McLean, 2000, <i>Velutina</i> J. Fleming, 1820.</p><p><i>Description:</i> Body of small to medium size for the family, 0.5–11.0 cm total length. Shell moderately thin to thick, weakly to strongly calcified; ear, shield or cap shaped, low to high spire, with expanded aperture; smooth or weakly sculptured by axial growth lines; exposed or completely enclosed by the mantle. Periostracum moderately or well developed, occasionally hairy.</p><p>Protoconch of 1.1–2.0 whorls; protoconch I of 0.50– 0.64 whorls, nucleus diameter 125–186 μm, smooth or with microgranules; protoconch–teleoconch boundary not always visible.</p><p>Mantle flat or dome shaped, outline rounded; thick or thin, with or without dorsal tubercles; with or without anterior and right lateral siphonal folds; texture smooth, wrinkled or jelly-like; colour highly variable, almost transparent to white, grey, beige, yellow, orange, brown, often patterned.</p><p>Penis to the right of the right cephalic tentacle, with tip of the seminal duct protruding from the penis tip. Vas deferens without a free loop in haemocoel.</p><p>Radula taenioglossate, formula 2:1:1:1:2, rachidian tooth squared, with broad base, rachidian cusp with or without one to six pronounced external denticles; lateral teeth squared or elongated, with a pointed triangular internal or external cusp, with or without one to six denticles on both sides; marginals narrow, with or without one small denticle on the internal side.</p><p>Jaws short to elongated, composed of scale-like elements, with denticles on the masticatory margin.</p><p><i>Distribution:</i> Arctic and temperate regions worldwide, 0–1200 m deep.</p><p><i>Remarks:</i> Velutinines can be diagnosed by their squared rachidian tooth with a broad base, and the jaws composed of scale-like elements, with denticles. Their shells can range from strongly calcified and completely exposed (e.g. <i>Velutina</i>) to almost without calcification and completely enveloped by the mantle (e.g. <i>Onchidiopsis</i>). Some genera (e.g. <i>Velutina</i> and <i>Limneria</i>) also have a hairy periostracum. In addition to the anterior inhalant siphon, an exhalant siphon is made by a right lateral mantle fold in some genera (e.g. <i>Marsenina</i> and <i>Onchidiopsis</i>). Before the present study, six genera (two of them with subgenera; see Gulbin & Golikov, 1997) were classified in this subfamily. However, the present molecular phylogeny suggests that <i>Limneria</i> and <i>Velutina</i> might be synonyms. In addition, pending molecular analysis of the type material, we propose to place <i>Pseudosacculus</i> in this subfamily, based on the description of the only included species, <i>Pseudosacculus okai</i> (Hirase, 1927). The radular formula (2:1:1:1:2) and morphology (Hirase, 1927: 125, fig. 8) and the presence of a small dorsal aperture in the mantle are congruent with this placement. It should be noted that Pelseneer (1935) suggested that <i>Pseudosacculus okai</i> might be classifiable in <i>Marsenina</i>, which would make <i>Pseudosacculus</i> a junior synonym.</p>