Reginella multipora (Sakakura, 1935) n. comb.

(Figs 14–15, 17)

Lyrula multipora Sakakura, 1935: 109, pl. 8, fig. 7.

Reginella furcata: Sakakura 1938: 96; Androsova 1959: 59, pl. 1, fig. 4; Mawatari 1988, 149, figs 9–14; Liu et al. 2001: 523, pl. 34, figs 1–2. Non Cribrilina furcata Hincks, 1882.

Figularia multipora: Silén 1941: 117, figs 178–180.

Cribrilina annulata: Liu et al. 2001: 512, pl. 32, fig. 5. Non Cellepora annulata Fabricius, 1780.

Material examined. Baengnyeong Island: Hwadong, 2 colonies; Junghwadong, 5 colonies; Dumujin, 1 colony; Gobongpo, 13 colonies.

Description. Colony encrusting, unilaminar, multiserial, up to 7 mm across, white. Autozooids more or less elongate-hexagonal with rounded corners, widest about mid-length. Frontal shield comprising 12–13 costae, pinnate except in suboral pair (Figs 14–15), more distal ones parallel-sided, more proximal ones triangular, opposing pairs meeting at weakly defined irregular median suture line; 4–8 (mostly 5–6) lacunae between adjacent costae. First pair of costae typically a little wider and thicker than succeeding costae, frequently with median ridge or peak where tips fuse. Two pseudopores on most costae, the outermost one larger; proximal triangular costae generally with only one pseudopore. No gymnocyst; costae originate at zooid margin. Autozooidal orifice transversely D-shaped, proximal margin straight or weakly convex. Articulated oral spines absent, but a stout process on each lateral margin may be weakly bifid, with distalmost tines of opposing processes occasionally meeting above distal oral rim; a pseudopore sometimes on lower outer face of each lateral process. No avicularia. Ooecium recumbent on distal zooid, smooth-surfaced with about 18–24 variable pseudopores (Figs 15, 17), thin median suture and sometimes a weak carina. Basal pore-chambers absent; uniporous mural septula present, each with relatively large communication pore. Ancestrula not seen.

Measurements. ZL, 325–333 (329) µm; ZW, 208–268 (234) µm; OrL, 57–68 (63) µm; OrW, 97–109 (102) µm; OoL 147–161 (154) µm; OoW 168–176 (172) µm.

Remarks. Reginella multipora is similar to the western North American species Reginella furcata (Hincks, 1882) and Reginella nitida Osburn, 1950 (see Soule et al. 1995), but differs from both in having, on average, fewer costae (12–16 in R. furcata, 14–17 in R. nitida), a non-concave proximal orificial rim, a stouter and wider pair of suboral costal with a median ridge or peak and proportionately larger costal pseudopores and ooecial pseudopores. Sakakura (1935) described the species from Toyama Bay, on the east coast of central Honshu, as having 13 costae; Mawatari (1988) noted 10–14 costae. Silén (1941) recorded it from Kyushu, with “about 13” costae.

Androsova (1971) described Lyrula hippocrepis possjeti from Possyet Bay, Russia, on the coast of the Japan Sea. Judging from her illustration, which includes latero-oral spinous processes, her taxon may belong to Reginella. It differs from R. multipora in having fewer costae (11), with apparently only one large pseudopore per costa.

Distribution. Southeastern Japan Sea, Bohai Sea, Yellow Sea, 0–274 m depth.