Salmoneus antricola Komai, Yamada & Yunokawa, 2015

Komai, Tomoyuki & Fujita, Yoshihisa, 2018, A new genus and new species of alpheid shrimp from a marine cave in the Ryukyu Islands, Japan, with additional record of Salmoneus antricola Komai, Yamada & Yunokawa, 2015 (Crustacea: Decapoda: Caridea), Zootaxa 4369 (4), pp. 575-586 : 584-585

Salmoneus antricola Komai, Yamada & Yunokawa, 2015

Fig. 6

Salmoneus antricola Komai, Yamada & Yunokawa, 2015: 414 , figs 1–5.

Material examined. RUMF-ZC 0 2731, 1 ovigerous individual (cl 4.3 mm), unnamed cave (sometimes called as “ Ohoba No. 2 Cave”), Ie Island, Okinawa Islands, Ryukyu Islands , Japan, 12 m deep, 18 July 2015, SCUBA diving, coll. K. Yunokawa & Y. Fujita; RUMF-ZC 0 2732, 1 non-ovigerous individual (cl 4.4 mm), same locality, 3 August 2015 , SCUBA diving, coll. K. Yunokawa.

Supplemental description. Telson ( Fig. 6C ) relatively narrow, slightly narrowing posteriorly in posterior twothirds, with 2 pairs of dorsolateral spiniform setae (anterior pair located at about mid-length of telson, posterior pair at 0.75 length); posterior margin truncate, with faint median notch, with 2 pairs of unequal, long spiniform setae (long outer seta about 0.3 times as long as telson, mesial seta 0.6 times as long as outer seta) and 1 pair of thin plumose setae medially ( Fig. 6D ).

Remarks. In the holotype of Salmoneus antricola , the telson is damaged, with its entire distal part missing ( Komai et al. 2015). Thus, the two additional complete specimens enable to supplement the original description of the species, by illustrating several previously unknown features of the telson ( Fig. 6C, D ). The two specimens also differ from the holotype of S. antricola in having subequal chelipeds of a “minor form”, with basis lacking a peculiar dorsal process described as characteristic for the species ( Fig. 6A, B ). In the holotype, the chelipeds are strongly asymmetrical in shape and dissimilar in size, with the left cheliped greatly enlarged, and the cheliped basis furnished with a strong dorsal process (cf. Komai et al. 2015). In all other features, the two specimens agree well with the holotype. The subequal condition of the chelipeds in the two recently collected specimens may be due to regeneration, genetic aberration or cheliped polymorphism.

Figures

FIGURE 6. Salmoneus antricola Komai, Yamada & Yunokawa, 2015. A, B, RUMF-ZC 02732, non-ovigerous individual (cl 4.4 mm); C, D, RUMF-ZC 02731, ovigerous individual (cl 4.3 mm). A, left pereopod 1(= cheliped), lateral view; B, right pereopod 1 (= cheliped), lateral view; C, telson, dorsal view; B, posterior part of telson, dorsal view.