Acidostoma molarifera Margulis, 1963

Stoddart, H. E. & Lowry, J. K., 2012, Revision of the lysianassoid genera Acidostoma and Shackletonia (Crustacea: Amphipoda: Acidostomatidae fam. nov.), Zootaxa 3307 (1), pp. 1-34 : 15

Acidostoma molarifera Margulis, 1963

Acidostoma molarifera Margulis, 1963: 165 , figs 1, 2. ― Barnard & Karaman, 1991: 457.

Diagnostic description. Mandible molar a small, weakly-setose triangular flap. Maxilla 1 palp small, 1- articulate, without apical setae. Maxilliped inner plate well developed; [outer plate, subapical notch unknown]. Gnathopod 2 dactylus reaching corner of palm. Pereopods 5 and 6 merus broader than long. Epimeron 3 posteroventral corner produced into a spine. Uropod 1 peduncle dorsolateral margin with more than 10 robust setae. Uropod 2 peduncle dorsolateral margin not castellate, with very short setae. Uropod 3 reaching to about the end of the peduncle of uropod 2; rami shorter than peduncle, without plumose setae; outer ramus article 2 small. Telson broader than long, moderately cleft (about 66%).

Remarks. Acidostoma molarifera and A. pectinata , both from the Sea of Okhotsk, share a small palp on maxilla 1, a large spine on the posteroventral corner of epimeron 3 and more than 10 robust setae on the peduncle of uropod 1. They differ in the mandibular molar (a weakly-setose triangular flap in A. molarifera , absent in A. pectinata ); the maxilla 1 palp (apical setae absent in A. molarifera , present in A. pectinata ) and the uropod 2 peduncle (dorsolateral margin smooth in A. molarifera and crenulate in A. pectinata ).

Distribution. Sea of Okhotsk, western North Pacific Ocean; 105 m depth.