Iphione hirotai Izuka 1912

Iphione hirotai Izuka, 1912 Iphione hirotai Izuka, 1912: 63–65, Pl. 7, Figs 8–15. Iphione muricata: Fauvel 1936: 51; Imajima & Hartman 1964: 17 (non Savigny in Lamarck, 1818). Remarks. Iphione hirotai Izuka, 1913 resembles I. ovata Kinberg, 1856, described from Hawaii and widely distributed from the Red Sea to the Eastern Pacific (Piotrowski et al. 2024). We did not have any specimens of the former species but, after the original description, and as indicated in the key above, the main differences are in the shape of nuchal lappets, and in the size and number or macrotubercles in elytra. Thus, I. hirotai has a truncate nuchal lappet, and its macrotubercles are digitate, up to twice longer than wide, arranged in 5–6 rows (body 14 mm long), whereas I. ovata has round nuchal lappet, and its macrotubercles are conical, 2–5 times longer than wide, and arranged in 3–5 rows (size-dependent). Izuka (1912) illustrated the elytra with smooth margins and with macrotubercles arranged in 5–6 rows. Because the presence of fimbriae was regarded as irrelevant, it was regarded as a junior synonym of I. muricata (Augener 1922: 5–6; Okuda 1937: 266). Imajima & Hartman (1964: 17) indicated neurochaetae were unidentate, with 11–12 rows of serrations, but Izuka (1912: 65, Pl. 7, Fig. 15) indicated 2–3 rows. Pettibone (1986: 16) noted there was no type material, and regarded it as a junior synonym of I. ovata Kinberg, 1856. Against this synonymy, it should be noted the lack of basal tubercle in dorsal cirrophores, as indicated by Izuka (1912, Pl. 7, Fig. 12), whereas it is present in I. ovata. Distribution. Originally described with a single specimen from one locality in Japan (Peel Island, Bonin Islands).