Richalpheus Anker and Jeng, 2006

Anker, Arthur & Dworschak, Peter C., 2007, Description of a new species of Richalpheus Anker and Jeng, 2006 (Crustacea: Decapoda: Alpheidae) from the Red Sea, Journal of Natural History 41 (37 - 40), pp. 2331-2340 : 2332-2333

Richalpheus Anker and Jeng, 2006

Revised diagnosis

Carapace glabrous, with anterolateral suture; branchiostegial margin with pronounced ventral lip and with rounded notch; cardiac notch well developed. Frontal margin without rostrum or orbital teeth. Pterygostomial angle rounded. Eyes concealed in dorsal and lateral view; anteromesial margin of eyestalk bluntly projecting. Antennular peduncle robust, first segment with ventromesial tooth; stylocerite appressed, distally blunt; second segment longer than wide; lateral antennular flagellum with very short accessory ramus. Antenna with basicerite moderately robust; carpocerite overreaching scaphocerite. Mouthparts typical for family; mandible with two-segmented palp; first maxilliped with elongate palp and expanded caridean lobe; second maxilliped with elongate epipod. Third maxilliped pediform, lateral plate produced, distally acute; tip of ultimate segment unarmed. First pereiopods (chelipeds) enlarged, very unequal in size, asymmetrical in shape, carried flexed; major cheliped with basis and ischium unarmed; merus slender, unarmed, ventral surface depressed; carpus short, cup-shaped; chela moderately large, subcylindrical; palm depressed longitudinally on ventromesial side, linea impressa absent; adhesive discs present; pollex with very shallow proximal depression or with shallow central fossa; dactylus unarmed or with flat bulge fitting into central fossa on pollex; no additional teeth on dactylus or pollex. Second pereiopod with four-segmented carpus; chela simple, with dense rows of stiff setae. Third pereiopod with unarmed ischium and merus, carpus with distal spine on ventral margin; propodus with spines on ventral margin, dactylus simple, conical. Fifth pereiopod with unarmed propodus, distally bearing well developed brush of setae. Sixth pleomere with more or less distinct articulated plate at posteroventral angle. Uropod with unarmed protopod; exopod distally truncate, diaeresis with deep incision and triangular tooth near mesial margin of exopod. Telson with two pairs of dorsal spines and two pairs of posterolateral spines; posterior margin rounded; anal tubercles present. Gill/exopod formula: 5 pleurobranchs (P1–5), 1 arthrobranch (Mxp3), 0 podobranch, 2 lobe-like epipods (Mxp1–2), 0 strap-like epipods 5 mastigobranchs, 0 sets of setobranchs, 3 exopods (Mxp1–3).

Type species

Richalpheus palmeri Anker and Dworschak, 2006 .

Other species included

Richalpheus dahabensis n. sp. (see below).

Distribution

Indo-West Pacific: presently known only from the Philippines and Egyptian Red Sea.