Thyone liaoi Yamana, Ogawa & Ohtsuka, 2021
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publication ID |
https://doi.org/ 10.11646/zootaxa.5023.1.1 |
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publication LSID |
lsid:zoobank.org:pub:E759FD85-1904-45A7-9A4D-56815FB9649B |
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persistent identifier |
https://treatment.plazi.org/id/312032A1-D924-4510-90DD-81749B7B1DE6 |
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taxon LSID |
lsid:zoobank.org:act:312032A1-D924-4510-90DD-81749B7B1DE6 |
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treatment provided by |
Plazi |
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scientific name |
Thyone liaoi Yamana, Ogawa & Ohtsuka |
| status |
sp. nov. |
Thyone liaoi Yamana, Ogawa & Ohtsuka View in CoL sp. nov.
[Japanese name: Kehada-namako ( Yamana 2016)]
( Figs 2B View FIGURE 2 , 3B View FIGURE 3 , 5A–H View FIGURE 5 )
Thyone pedata: Liao & Clark 1995: 505–506 View in CoL , Fig. 307 a, b; Yamana 2016: 7, Fig. a.
non: Thyone pedata Semper, 1867 View in CoL –8: p 67. (see Remarks)
Material examined. Holotype, WMNH-INV-2014-182 (ST- 7 in 2014, 6 November 2014, anesthetized length 36 mm, width 10 mm, INSD accession number LC547978 View Materials , 622 bps, Fig. 2 View FIGURE 2 B-e) . Paratypes: WMNH-INV-2014-183 (ST- 7 in 2014, 6 November 2014, length 39 mm, width 9 mm, eviscerated, Fig. 2 View FIGURE 2 B-f); WMNH-INV-2014-184 (ST- 7 in 2014, 6 November 2014, length 34 mm, width 9 mm, Fig. 2 View FIGURE 2 B-g); WMNH-INV-2014-188 (ST- 4 in 2014, 5 November 2014, anterior half only, length 13 mm, width 5 mm, Fig. 2 View FIGURE 2 B-h).
Diagnosis. Bodywall table ossicles with distorted oval or rhomboidal disc and delicate spire, mostly with one pillar formed by fusion of two pillars and spire with 4–6 minute apical spines. Pedicel supporting table ossicles with narrow curved disc with 2–4 large central perforations and 2–8 small distal perforations; spire high, with two (occasionally three) pillars united distally, ending in 2–4 minute processes.
Description. Body medium, up to 39 mm long, fusiform, curved, with both ends tapered and turned slightly upwards ( Fig. 2B View FIGURE 2 ); bodywall thin, soft. Color fading upon preservation. Living body color whitish orange. Tentacles 10, arranged in a single circle, two medioventral tentacles smaller than the other eight. Tentacles and introvert transparent in most parts in living animals, and with some dark brown pigmentation. Several rows of villi surrounding oral opening. Oral disk and pharynx of the preserved specimens dark grayish brown and dark purplish brown, respectively. Pedicels long, non-retractile, covering entire body at constant density, lacking in introvert region. Color of pedicels same and slightly deeper than adjacent body. Pedicels becoming gradually smaller toward anterior and posterior from middle portion of body. Ten anal papillae and five anal teeth in radii. After preservation, color denoted above turned more yellowish and whitish than that of living color.
Calcareous ring long, cracking of mosaic patterns mostly caused by the damage of material; main radial plates and interradial plates not fragmented in original condition in the several well preserved specimens ( Fig 3B View FIGURE 3 ). Radial elements elongated, with paired, posterior, weakly fragmented prolongations; each with an anterior projection and notch. Interradial elements also long but without posterior prolongations with slight anterior projections; shortest in dorso-lateral elements. Radial plates and interradial plates loosely adherent. One (or rarely two) Polian vesicles in medioventral, single stone canal in mediodorsal position. Well-matured gonad situated in mid-body, in two clumps, one on each side of dorsal mesentery, most tubules not branched. Gonad lacking ossicles.
Bodywall ossicles comprising abundant tables ( Fig. 5F, G View FIGURE 5 , Table 4), with distorted, oval or rhomboidal disc and delicate spire, mostly with two pillars fusing into one distally, ending in 4–6 minute apical spines. Table disc with 8–16 perforations, most frequently 8–10; central two perforations large, peripheral perforations small.
Tentacle ossicles comprising mostly plates of varying size and shape in trunk and branches, also table ossicles in basal parts ( Fig. 5A View FIGURE 5 , Table 4). Table ossicles with distorted oval or rhomboidal disc, and high spires with twopillars with mostly 2–3 crossbeams, and 4–8 apical spines. Some table ossicles have oval discs, possessing two larges central perforations and small distal perforations. Plates elongated, with two, large, central perforations and small distal perforations, occasionally developing a rudimentary spire and/or extra layer in central part. Peri-oral skin ossicles comprising mostly rosettes, with tables in part adjoining tentacle bases ( Fig.5B View FIGURE 5 , Table 4). Rosettes have granulated, mulberry-like, densely branched in more than one plane branches. Tables with distorted oval or rhomboidal discs, high spires with two-pillars, mostly with 1–3 crossbeams and 4–6 apical spines. Occasionally plates also exist, some with rudimentary spires and/or extra layer in central part. Pharyngeal villi have rosettes with granulated, mulberry-like ( Fig. 5C View FIGURE 5 , Table 4). Introvert with tables and mulberry-like rosettes ( Fig. 5D View FIGURE 5 , Table 4). Table ossicles with distorted, oval or rhomboidal disc, and low spires of two-pillars, with mostly 1–2 crossbeams, and 4–8 minute apical spines, occasionally with an extra layer in central part. Rosettes with granulated, mulberrylike.
Most pedicels with endplate and supporting tables ( Fig. 5E View FIGURE 5 , Table 4). Supporting tables with narrow, curved disc, with 2–4 large, central perforations and 2–8 small, distal perforations; spire high, with two (occasionally three) pillars united distally, ending in 2–4 minute processes ( Fig. 5E View FIGURE 5 , Table 4). Endplates with holes arranged in three concentric areas, viz., commarginally-elongated holes near rim, radially-elongated holes in mid-region, and almost circular holes in central area. Anal papillae with small, irregular supporting plates and tables ( Fig. 5H View FIGURE 5 , Table 4). Skin around anus with relatively small and simple tables.
Remarks. Thyone liaoi sp. nov. was previously reported as a regional form of “ Thyone pedata Semper, 1867 ,” from the Chinese and Japanese waters (e.g., Liao & Clark 1995, Yamana 2016), because the bodywall ossicle morphologies (reported in Clark & Rowe 1971; Liao & Clark 1995; and the present study) of these species resemble each other. However, Semper (1867 –8) plainly stated that the gonadal tubules of this species have needle-shaped ossicles and that the bodywall possesses quite large ossicles. (These ossicle morphologies were not mentioned in Semper 1867 –8, p 67). The presence of such ossicles were not observed in the present new species. From seas worldwide, there are more than 60 nominal species and subspecies in the genus Thyone (65 or 68 species/subspecies nominated in WoRMS 2021b), in which 14 species are presently classified into the Group III (comprising species with both rosettes and tables in the introvert) congeners which had been implied by Deichmann (1930), Panning (1949) and Pawson & Millar (1981). The present new species also should be involved into this group as 15th species (Table 8). Among the 15 species of Group III, this species have the four identical characters: 1) granulated, mulberry-like small rosettes ( Fig. 5B–D View FIGURE 5 ) are detected from the peri-oral, pharynx, and introvert skin; 2) length (approx. 70–160 µm) of the bodywall table disc ( Fig. 5F, G View FIGURE 5 ) is exceedingly larger than that of the other 14 species (Table 8-2); 3) length (approx. 30–430 µm) of the tentacle ossicles ( Fig. 5A View FIGURE 5 ) is exceedingly larger than that of the other 14 species (Table 8-2); 4) the two-pillared spire of the bodywall table is united one-pillar with 4–6 minute apical spines ( Fig. 5F, G View FIGURE 5 ), but not forming a crown. From these features, this new species is easily distinguished from the 14 species of the Group III and other 24 species of undetectable group of Thyone (Table 8).
Distribution. Known from the Gulf of Tonkin, China, depth 55 m ( Liao & Clark 1995), and several localities in the Seto Inland Sea, Japan: middle and eastern parts of the Seto Inland Sea, sand bottom, depth 26 m (ST- 4 in 2014); mud bottom, depth 25–27 m (ST- 7 in 2014), and northen part of the Kii Strait, sand bottom, shallow water ( Yamana 2016).
Etymology. The species named in honor of the famous researcher Dr. Yulin Liao of the Institute of Oceanology, Academia Sinica (IOAS) Qingdao, China, who first reported this species as Thyone pedata .
Molecular data comparison. In BLAST searches, the obtained partial COI gene sequence is deeply divergent from all other sequences. A sequence identified as Paelopatides sp. (INSD accession number KX874356 View Materials , 80.6% similarity with 100% coverage) was closest (meaningless at generic/family level).
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
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Thyone liaoi Yamana, Ogawa & Ohtsuka
| Yamana, Yusuke, Nakaguchi, Kazumitsu, Yamaguchi, Shuhei, Katoh, Mikio, Ogawa, Akito & Ohtsuka, Susumu 2021 |
Thyone pedata:
| Yamana, Y. 2016: 7 |
| Liao, Y. & Clark, A. M. 1995: 506 |