Petrolisthes cinctipes ( Randall, 1840 )

Wicksten, Mary K., 2012, Decapod Crustacea of the Californian and Oregonian Zoogeographic Provinces 3371, Zootaxa 3371, pp. 1-307 : 158

Petrolisthes cinctipes ( Randall, 1840)

( Fig. 37B, Pl. 8A)

Porcellana cinctipes Randall, 1840: 136 .

Petrolisthes cinctipes . — Holmes 1900: 107 (part). — Rathbun 1904: 168. — Schmitt 1921: 179, fig. 113, pl. 32, fig. 1. — Johnson & Snook 1927: 351. — Haig 1960: 90, pl. 28, fig. 3 (extensive synonymy). — Wicksten 1973: 161. — Gonor & Gonor 1973: 225. — Haig & Abbott 1980: 588, fig. 24.18. — Hart 1982: 98, fig. 3. — Ricketts et al. 1985: 45, fig. 30. — Jensen 1995: 75, fig. 149. — Kuris et al. 2007: 648, pl. 326 A.

Diagnosis. Front strongly deflexed, triangular, with deep median groove. Carapace about as long as wide, covered with fine granules. Chelipeds covered with fine granules, without setae. Merus with strongly projecting lobe on anterior margin. Carpus 1.5–2 times as long as wide, strong lobe occupying more than 0.25 of proximal anterior margin, anterior, posterior margins converging distally, posterior margin with row of tubercles forming ridge, ending distally in strong tooth. Chela smooth, gape with tuft of setae. Pereopods 2–4 rugose, merus unarmed, usually naked, that of third leg inflated; carpus nearly devoid of setae; propodus, dactyl with setae. Carapace length to 24 mm.

Color in life. Light to dark brown, granules bluish, with blue, white comma-like mark on either side of cardiac area. Chelipeds with red spot at base of dactyl. Pereopods 2–4 with yellow median band on propodus, dactyl yellow with narrow brown band. Outer segments of maxillipeds red. Individuals ready to molt may be blue ( Hart 1982).

Habitat and depth. Under rocks or among mussel beds, midlittoral zone, rarely as deep as 64 m.

Range. Porcher I., British Columbia to Santa Barbara, California. Type locality incorrectly given as "Sandwich Islands" (Hawaiian Is.). Some of Randall's specimens were collected at or near Monterey, California, which may be the actual type locality .

Remarks. This is another very common intertidal crab, often found under rocks in rubble beds in the midlittoral zone. In life, pereopods 5 are folded alongside the carapace. Records of P. cinctipes from south of Point Conception prior to 1945 are likely to be misidentifications of P. cabrilloi .