Elasmopus tiburoni J. L. Barnard 1979

Elasmopus tiburoni

Elasmopus rapax form I of Tiburon Island.—J. L. Barnard, 1969b: 119 [part].

DIAGNOSIS.—Eyes ordinary. Mandibular palp article 3 deeply falcate. Palm of male gnathopod 2 with ordinary spinose hump near dactylar hinge but hump weak and concealed laterally by flange-like inflation of entire palm, with dactyl overriding face of palm, medial face of palm deeply hollowed as in E. pocillimanus (Bate), palm and hollow defined by small tapering medial tooth but third tooth absent, hollow defined anteriorly by sharp setose ridge, palmar margin nearly naked, posterior margin of hand densely setose but setae in rows of short to long. Article 2 of pereopods 3–5 with long posterior setae in male only; locking spines of pereopods 1–5 ordinary, inner margin of dactyl usually smooth but occasionally with 1–2 notches (forming broad castellations) and minute proximal shagreen, main subapical setule thick but apically flexible; articles 4–5 of pereopods 4–5 especially broad in comparison to E. rapax, increase in breadth confined primarily to male. Epimera 1–3 with long ventral setae and short spines; epimeron 3 with nearly straight posterior margin armed with notches bearing setules, margins between notches flat except for ultimate posteroventral tooth and one tooth dorsal to it, these teeth small and of subequal size, sinus above ultimate tooth lacking setule. Rami of uropod 3 equally long in male, inner ramus with several stout basomedial spines, inner ramus in females and juveniles shorter than outer ramus. Telson with naked protrusive apices placed mediad, laterally defined by sinus and sharp tooth, spines submarginal from sinus and forming row of 2–4 laterally, but row extending mediad across axis of each lobe, male with 2 short spines, female with 4 long spines on each lobe.

DESCRIPTION.—Following parts not illustrated and as shown for E. rapax (Figures 35–37): head, antennae, accessory flagellum, eye (slightly larger than in E. rapax), mouthparts, pereopods 1–2, dactyls, urosome, uropods 1–2. Female gnathopod 2, coxae, cuticle, medial view of article 1 on antenna 1; female lacking long setae of article 2 on pereopods 3–5, small females and juveniles lacking serrations of epimeron 3 except for ventralmost sinus and tooth. Juvenile males with gnathopods like juvenile E. rapax; female uropod 3 with 3 apicomedial peduncular spines instead of 2 as in Figure 37: wR3 of E. rapax.

HOLOTYPE.—USNM 149405, male “f,” 8.76 mm (illus.).

TYPE-LOCALITY.—SCO 12, Puerto Peñasco, Mexico, 23 February 1971, intertidal, wash of Colpomenia sp.

VOUCHER MATERIAL.—Type-locality, female “w,” 6.58 mm (llus.).

DISTRIBUTION.—Gulf of California; Puerto Peñasco, Bahía Kino, Turners Island south of Isla Tiburon, Bahía San Carlos, Guaymas, Bahía San Evaristo, Isla Espiritu Santo; found in shells of hermit crab in SNY 1; intertidal.