Leptoplax doederleini ( Thiele, 1909 )

Sirenko, Boris I. & Zhang, Junlong, 2019, Chitons (Mollusca: Polyplacophora) of Hainan Island and vicinity, South China Sea, Zootaxa 4564 (1), pp. 1-40 : 27-28

Leptoplax doederleini ( Thiele, 1909)

( Figs 19–21 )

Notoplax döderleini Thiele 1909: 39 , pl. 5, figs 32–38; Kaas & Van Belle 1980: 40; 1998: 64; Xu 2008: 458.

Notoplax (Notoplax) doederleini ; Van Belle 1982: 478, fig. 4.

“ Notoplax ” doederleini ; Saito 1998: 160, fig. 2N; 2000a: 102.

Leptoplax doederleini ; Saito 2000: 21, pl. 10, fig. 6; 2001: 200, fig. 14; 2006: 217; 2017: 54, 737, pl. 10, fig.8; Sirenko & Saito 2017: 460, figs 9–12, 43D. Type material. Holotype ZMB Moll. 102017.

Type locality. Kajiyama (=? Katsuyama, Tokyo Bay), Japan .

Material examined. South China Sea, Hainan, Xincun, corals and Zostera sp., 0.5 m, 1 spm, BL 10.5 mm, 21.04.1958.

Distribution. From Pacific coast of central Japan to Okinawa, Hong Kong, Hainan and northern Vietnam, 0– 20 m.

Remarks. Van Belle (1982) reported this species from Hong Kong for the first time. Specimens from Hainan ( Fig. 20D , this study) and from Vietnam ( Fig. 11 , Sirenko & Saito 2017) differ from specimen from specimens from Hong Kong ( Fig. 4 , Van Belle 1982) by the shape of the central tooth of the radula. The studied specimen (BL 10.5 mm) has a radula that is 3.5 mm long with 37 transverse rows of mature teeth and 11gills extended from valve V to valve VII. Slit formula of this specimen is 5/1/8.

Figures

FIGURE 4. Complete specimens of species of genera Plaxiphora, Placiphorella, Acanthochitona, and Cryptoplax: A. Plaxiphora bucklandnicksi, Hainan Island, Sanya, stn 13, BL 5.0 mm; B. Placiphorella stimpsoni, Hainan Island, Sanya, BL 23.0 mm; C. Acanthochitona britayevi, Hainan Island, Xincun, BL 8.0 mm; D. Acanthochitona intermedia, Xisha Islands, MBM 100328 BL 11.0 mm; E. Acanthochitona lanae, Hainan Island, stn 1 BL 5.0 mm; F. Cryptoplax larvaeformis, Xisha Islands, 57-419, BL 35.0 mm; G. Cryptoplax oculata, Xisha Islands, 57-419, BL 35.0 mm.

FIGURE 11. Lucilina lamellosa forma costata, Hainan, Xincun, BL 9.0 mm: A. Valve V, detail of tegmentum in pleural and lateral areas; B, C. Dorsal spicules; D. Ventral scales.

FIGURE 19. Leptoplax doederleini, Hainan, Xincun, BL 10.5 mm: A. Valve I, dorsal view; B. Valve II, dorsal view; C. Valve V, dorsal view; D. Valve VIII, dorsal view; E. Valve IV, ventral view; F. Valve V detail of tegmentum in plurolateral and jugal areas; G. Valve V, rostral view; H. Valve VIII, lateral view.

FIGURE 20. Leptoplax doederleini, Hainan, Xincun, BL 10.5 mm: A. Valve VIII, view from behind; B. Marginal needles; C. Dorsal spicules and dorsal and marginal needles; D. Needles in tufts.

FIGURE 21. Leptoplax doederleini, Hainan, Xincun, BL 10.5 mm: A. Dorsal and ventral needles; B. Dorsal needles in suture; C. Dorsal spicules around tuft; D. Radula.