Petrolisthes cabrilloi Glassell, 1945

Wicksten, Mary K., 2012, Decapod Crustacea of the Californian and Oregonian Zoogeographic Provinces 3371, Zootaxa 3371, pp. 1-307 : 156

Petrolisthes cabrilloi Glassell, 1945

( Fig. 37A, Pl. 8B)

Petrolisthes cabrilloa Glassell, 1945: 225 , fig. 4. — Kropp 1981: 307.

Petrolisthes cabrilloi . — Haig 1960: 88, pl. 26, fig. 3. — Haig et al. 1970: 26. — Haig & Abbott 1980: 588, fig. 24.17. — Jensen 1995: 76, fig. 153. — Kuris et al. 2007: 648. — Sloan et al. 2010: 159.

Diagnosis. Front triangular, with deep median sulcus. Carapace about as long as broad, usually covered with plications, fine granules; but sometimes nearly smooth. Chelipeds finely granular. Merus with strongly projecting lobe on anterior margin. Carpus setose, about twice as long as wide, with small lobe occupying about 0.25 of proximal end, granules along outer margin enlarged, forming crest ending distally in sharp tooth. Chela smooth to lightly pubescent, gape with thick pubescence. Pereopods 2–4 rugose, merus of pereopod 3 unarmed, not inflated; all segments with tufts of setae. Carapace length to 16 mm.

Color in life. Carapace brown to tan, with striations, numerous spots of pale greenish white. Chelipeds brown, chela may have greenish tinge, red spot at base of dactyl. Pereopods 2–4 dull brown, with bands of tan, darker brown on propodus. Outer segments of maxillipeds red ( Haig 1960).

Habitat and depth. Among rubble, on pilings or among mussels, intertidal zone.

Range. Morro Bay , California to Magdalena Bay , Baja California, Mexico, including Santa Cruz and Santa Catalina Is. , California. Type locality Anaheim Landing, California .

Remarks. This porcelain crab seems to replace P. cinctipes south of Point Conception, California. It is extremely common. As many as 22 individuals were found under a single rock with area of about 0.9 m 2 among rocky rubble near Point Fermin, Los Angeles County, California. Sloan et al. (2010) reported that it is parasitized by the rhizocephalan Lernaeodiscus porcellanae . They also noted that the sizes of the largest individuals in a population varied geographically even among sites separated by only a few kilometers, perhaps in response to food.