Leptochiton fairchildi ( Iredale & Hull, 1929 )

Sirenko, Boris, 2020, New Zealand and Australian species of the genus Leptochiton (Mollusca Polyplacophora), Zootaxa 4851 (3), pp. 401-449 : 409

Leptochiton fairchildi ( Iredale & Hull, 1929)

( Figure 9 )

Lepidopleurus kerguelenensis ; Hedley 1916: 34. Non Leptochiton kerguelensis Haddon, 1886 .

Terenochiton fairchildi Iredale & Hull 1929: 79 , pl. 9, figs. 18–19; Cotton 1937: 12; Dell 1964: 268; Powell 1979: 21. Leptochiton (Leptochiton) fairchildi ; Kaas & Van Belle 1985: 156, fig. 71, map 28.

Type material. Holotype ( AM C.46625).

Type locality. New Zealand, Macquarie Island .

Material examined. New Zealand, Macquarie Island, R / V Eltanin , cruise 27, stn 1972, 54°30’S, 158°58’E, 31 m, 10 spms, BL 2.4–6.0 mm, 15.02.1967 ( USNM?) ; Macquarie Island, R / V Dmitriy Mendeleev 30 m, 1 damaged spm ( ZISP 2380 ), BL ca. 4 mm, 21.01.1976, leg. V . Averintsev.

Distribution. Only known from Macquarie Island, on rocks, 30– 69 m.

Remarks. Available specimen (BL ca. 4 mm) from Macquarie Island (30 m, R/V Dmitriy Mendeleev, 21.01.1976) was very damaged and it was only possible to study pieces of head and intermediate valves and the radula by SEM. It turned out that the tegmentum is smooth with very small, narrow grooves and with megalaesthete pores only, which are arranged in quincunx. The studied specimen has a radula with a length of about 1 mm and 24 transverse rows of mature teeth. The cusp of the major radular lateral tooth is tridentate, the denticles are almost of equal size. The specimen from the USNM sample with BL 6.0 mm has 7 gills arranged from valve six to anus. Besides the different radulae L. fairchildi differs from L. kerguelensis in the absence of granules in tegmentum but the presence of growth marks.

Figures

FIGURE 9. Leptochiton fairchildi, New Zealand, Macquarie Island, (ZISP 2380) 30 m, R/V Dmitriy Mendeleev, 21.01.1976. A. Part of head valve, dorsal view; B. Part of intermediate valve, dorsal view; C. Radula; D. Central, first and major lateral teeth of radula.