Hesperarion niger

(J.G. Cooper, 1872)

Black Westernslug

G2Imperiled Found in 2 roadless areas NatureServe Explorer →
G2ImperiledGlobal Rank
Identity
Unique IDELEMENT_GLOBAL.2.113261
Element CodeIMGAS60020
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryInvertebrate Animal
KingdomAnimalia
PhylumMollusca
ClassGastropoda
OrderStylommatophora
FamilyArionidae
GenusHesperarion
Concept Reference
Turgeon, D. D., J. F. Quinn, Jr., A. E. Bogan, E. V. Coan, F. G. Hochberg, W. G. Lyons, P. M. Mikkelsen, R. J. Neves, C. F. E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F. G. Thompson, M. Vecchione, and J. D. Williams. 1998. Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks. 2nd Edition. American Fisheries Society Special Publication 26, Bethesda, Maryland. 526 pp.
Conservation Status
Review Date2002-10-08
Change Date2002-10-08
Edition Date2004-05-03
Edition AuthorsCordeiro, J.
Range Extent100-1000 square km (about 40-400 square miles)
Number of Occurrences6 - 20
Range Extent Comments
In northern California in Shasta, Humboldt, and Glenn Counties (Roth, 2004).
Occurrences Comments
Root Creek, Reynolds Basin at Shasta Lake, Whiting Ridge, Tool Cache Ridge, California (Roth, 2004).
Ecology & Habitat

Description

Body blackish brown to reddish gray, somewhat lighter on the sides, with numerous small, irregular, black spots scattered over surface, some joining in oblique reticulation along mucus grooves of flanks. Mantle of same ground color as rest of body. Foot fringe tan to gray, vertically striped with black. Sole uniform, white to light tan, unmarked or with two longitudinal rows of black spots defining lateral zones. Internal shell a low-arched plate with off-center terminal nucleus; periostracal margins extending beyond calcified part of shell. Caudal mucus pore prominent. Penis cylindrical, with blunt summit, constricted at base. Penial retractor muscle broad, strap-shaped, inserted at summit of penis. Verge broadly conical, much smaller than cavity of penis. Vas deferens long, slender, convuluted near middle of its length. Epiphallus entering summit of penis, of uniform diameter, throughout. Atrium containing three massive pilasters, with either appendix present at base, broad below and tapering to vermiform tip, or else broad sac on right side, containing multiple, tusk-shaped calcareous darts. Free oviduct as long as or moderately longer than vagina (Roth, 2004).
Other Nations (1)
United StatesN2
ProvinceRankNative
CaliforniaSNRYes
Roadless Areas (2)
California (2)
AreaForestAcres
Ferguson RidgeSierra National Forest6,104
Trumbull PeakStanislaus National Forest6,164
References (1)
  1. Turgeon, D. D., J. F. Quinn, Jr., A. E. Bogan, E. V. Coan, F. G. Hochberg, W. G. Lyons, P. M. Mikkelsen, R. J. Neves, C. F. E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F. G. Thompson, M. Vecchione, and J. D. Williams. 1998. Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks. 2nd Edition. American Fisheries Society Special Publication 26, Bethesda, Maryland. 526 pp.