Acila insignis

Acila insignis (A. Gould, 1861) (Fig. 2 C, D) Nucula (Acila) insignis A. Gould, 1861: 36. Acila (Truncacila) insignis (Gould, 1861) — Lutaenko & Noseworthy 2012: 21, pl. 1, figs. G–J, text-fig. 3. Material examined: 12 specimens from the Kunashirsky Strait (50– 1,000 m). Distribution: Yellow Sea; Sea of Japan; Kuril Islands (Kunashir Island (Izmena Bay)), Kunashirsky Strait (5– 1,000 m) (Scarlato 1981; Evseev 2000; Kurozumi & Tsuchida 2000, 2017; Kantor & Sysoev 2005; Lutaenko & Noseworthy 2012; Lee 2014). Remarks: The finding of this species in Izmena Bay (Kunashir Island) was only briefly mentioned by Evseev (2000). In other parts of its range, it was found only to a depth of 650 m (Lee 2014). Acila insignis well differs from Acila divaricata by the absence of a distinct radial fold and a rostrum at the posterior end of the shell.