Pacifastacus nigrescens

Pacifastacus nigrescens (Stimpson, 1857) (Fig. 30B, K) Astacus nigrescens Stimpson, 1857a: 87; 1857b: 492. — Hagen 1870: 92, pl. III, fig. 168. — Holmes 1900: 166. — Bonnot 1930: 212. Pacifastacus nigrescens. — Riegel 1959: 44 (part, figures probably are of P. fortis). — Hobbs 1976: 23, fig. 13b, 14d. — Kuris et al. 2007: 636.— Larson & Olden 2011: 62. Diagnosis. Similar to P. leniusculus except rostrum concave, with prominent, acute apex; 5 or 6 lateral teeth, small spinules on postorbital ridges. Major chelae without clusters of setae, chela narrow, palm barely wider than closed fingers, fingers may be gaping. Abdominal pleura sharply triangular. Total length 78 mm. Color in life. Blackish. Habitat and depth. Streams near the coast. Depth not reported. Range. Unalaska, Alaska; Fort Steilacoom, Washington, Alameda Creek, Alameda County and Coyote Creek, Santa Clara County, California (Holmes 1900). Type locality given as San Francisco, California, but Stimpson said that he purchased his specimens in a market. Remarks. There have been no reliable records of live P. nigrescens since those of Holmes (1900). Subsequent reports by Bonnot (1930) quoted Holmes or considered P. fortis to be a subspecies of P. nigrescens (Riegel 1959). Holmes' specimens probably were burned in the fire following the San Francisco earthquake in 1906, so it is impossible to double-check the identification of his material from Washington and Alaska.
Published as part of Wicksten, Mary K., 2012, Decapod Crustacea of the Californian and Oregonian Zoogeographic Provinces 3371, pp. 1-307 in Zootaxa 3371 on page 127
{"references":["Stimpson, W. (1857 a) Notices of new species of Crustacea in western North America being an abstract from a paper to be published in the Journal of the Society. Proceedings of the Boston Society of Natural History, 6, 84 - 89.","Stimpson, W. (1857 b) On the Crustacea and Echinodermata of the Pacific shores of North America. Journal of the Boston Society of Natural History, 6, 444 - 532.","Hagen, H. A. (1870) Monograph of the North American Astacidae. Illustrated Catalogue of the Museum of Comparative Zoology at Harvard College, 3, 1 - 109.","Holmes, S. J. (1900) Synopsis of California stalk-eyed Crustacea. Occasional Papers of the California Academy of Sciences, 7, 12 - 62.","Bonnot, P. (1930) Crayfish. California Fish and Game, 16, 212 - 216.","Riegel, J. (1959) The systematics and distribution of crayfishes in California. California Fish and Game, 45, 29 - 50.","Hobbs, H. H. Jr. (1976) Crayfishes (Astacidae) of North and Middle America. United States Environmental Protection Agency, Water Pollution Control Research Series 18050 ELDO / 72, Cincinnati, Ohio, 173 pp.","Kuris, A. M., Sadeghian, P. & Carlton, J. T. (2007) Keys to Decapod Crustacea. In: Carlton, J. T. (Ed.) The Light and Smith Manual: Intertidal Invertebrates Central California to Oregon. University of California Press, Berkeley, 4 th ed., pp. 636 - 656.","Larson, E. R. & Olden, J. D. (2011) The state of crayfish in the Pacific Northwest. Fisheries, 36, 60 - 73."]}