Procambarus clarkii ( Girard, 1852 )

Wicksten, Mary K., 2012, Decapod Crustacea of the Californian and Oregonian Zoogeographic Provinces 3371, Zootaxa 3371, pp. 1-307 : 128

Procambarus clarkii ( Girard, 1852)

( Fig. 30O, Pl.5B)

Cambarus clarkii Girard, 1852: 91 . — Hagen 1870: 39, pl. I, figs, 7–10, 99,100; pl. II, figs, 133–134; pl. IV.

Procambarus clarkii . — Hobbs 1976: 72, fig. 56d. — Rodriguez-Alvarez & Campos 1994: 729. — Johnson & Johnson 2008: 69, photo pages 70–72. — Kuris et al. 2007: 636. — Larson & Olden 2011: 66, p. 69 fig. D.

Diagnosis. Rostrum shorter than scaphocerite or antennular peduncle, with one pair teeth on postorbital ridge. Carapace somewhat granulate. Width of areola very narrow, cervical groove, branchiocardiac grooves delineating small triangular area on dorsal surface. Cervical tooth present. Third maxilliped setose, its ischium with inner distal margin ending in large tooth. Chelipeds narrow. Ischium with teeth in line with those of merus. Merus with teeth, tubercles on upper surface, distal margin, row of teeth on lower margin, smaller row mesial to this row. Carpus with 2 large inner teeth as well as tubercles. Palm of chela tuberculate, with teeth on inner margin; fingers longer than palm. Fixed finger with 2 large, 2 small teeth on cutting edge near proximal end. Dactyl may be concave on outer margin, with 2–3 tubercles on proximal end. Pereopods 2, 3 chelate, smooth. Pereopods 3, 4 with ischial hooks. Pereopods 4, 5 with simple dactyls. Abdominal pleura diminishing in size from 1–5, pleura blunt or with minute terminal tooth curved posteriorly. Pleura of abdominal somite 6 forming hook around base of uropods. Abdominal somites 1, 2 with dorsal sulci running across dorsal surface. Male pleopod 1 with prominent shoulder on cephalic surface. Male pleopod 2 with calcified endopod, soft exopod. Telson with lateral, median sulci, V-shaped fissure with 2 teeth on each side of fissure. Outer uropod with fissure and lateral tooth, also median ridge; inner uropod with lateral spine, median ridge. Male total length 82 mm, female smaller.

Color in life. Juveniles often camouflaged, brown, striped, or mottled; adults bluish to dark green, often with red spots on chelipeds; lower parts orange in breeding adults. Albinos are rare. Johnson & Johnson (2008: 70–72) gave a series of photographs of many color morphs of this species.

Habitat and depth. Ponds, shallow streams, ditches, lakes, shore to at least 6 m. After floods, has been found crossing wet ground and can be washed into estuaries.

Range. Native to southern Illinois to northern Mexico and Escambia County, Florida , but introduced widely elsewhere, including California and northern Mexico. Reported as far south as Ensenada in Baja California Norte and San Juan River in Nuevo Leon, Mexico ( Rodriguez-Almaraz & Campos 1994); also introduced into Europe and Japan. Type locality " between San Antonio and El Paso del Norte, Texas. ” Larson & Olsen (2011: fig. 1) gave a map of the distribution in Oregon, Washington, Idaho and Utah .

Remarks. The red swamp crayfish has been introduced as bait or for use in aquaculture in many areas of the United States and Mexico, and now may well be the most abundant and widely distributed crayfish in North America. Any crayfish found in southern California is likely to be this species or the preceding one.