Hyperia leptura Bowman 1973

Hyperia leptura

DERIVATION OF NAME.–From the Greek “leptos” [=slender] + “oura” [=tail], referring to the slender uropods.

TYPE.–Holotype and only specimen, ♀ with embryos in marsupium, USNM 111244, from CalCOFI Cruise 20, station 130.35, off Bahía Ballenas, Baja California (26°19.5′N, 113°49′W), in 140–0 m net tow, 14 November 1950.

DIAGNOSIS.–Head longer than pereonites 1–2 combined; gland cone rounded. Outer lobe of Mxp with several long setae near inner margin; inner lobe about half as long as outer lobe, anterior surface heavily setose, apex with single strong spine. S2 of P1–2 relatively narrow, about 2.5 times as long as wide, with a number of short setae on proximal part of anterior margin; s5–6 long and narrow, armed with numerous long spines. P3–4 long; posterior margins of s3–6 spinose; posterior margin of s6 finely serrate. Setae on P5–7 limited to a few on anterior margins of s2 and s5 (Figure 17j–k). Epimera of pleonite 3 not produced posteriorly. Up1–3 long and slender; rami lanceolate, those of Up1 especially long. Telson slightly shorter than width at base.

RELATIONSHIPS.–Only one specimen of this species has been discovered, but its characters are so distinctive that I have no hesitation in establishing a new species for it. It appears to be closest to H. macrocephala, but in addition to its much smaller size, it differs in the form of coxa 4, pleonal epimera 3, the Mxp, and the narrower peduncle of Up3.