> Key to the Pleuroceridae of Virginia

Disclaimer: This key is intended for use with the 12 species and subspecies of pleurocerid gastropods inhabiting the Commonwealth of Virginia. The management will not be responsible for any loss, damage, or injury resulting from its application elsewhere.  Drainages are A = Atlantic, N = New, S = Big Sandy,  T = Tennessee.

1a) Shell with prominent siphonal canal, often bearing spines . . . . Io fluvialis (T)
1b) No siphonal canal . . . . (2)


2a) Shell height greater than 1.7 times width . . . . . . (4)
2b) Shell height less than 1.7 times width . . . . . . (3)


3a) Shell never carinate, tentacles constricted at eye, body bluish gray  . . . . . . Leptoxis praerosa (T, N)
3b) Shell often carinate, tentacles taper gradually, body dark with orange or yellow hue  . . . . Leptoxis carinata (N, A)


4a) Shells bearing costae, at least on early whorls . . . . (5)
4b) Shells completely uncostate . . . . (6)

5a) Spiral cords present over entire surface of shell . . . Goniobasis catenaria catenaria (A) 
5b) If spiral cords are present, they are restricted to juvenile whorls only . . . Goniobasis catenaria dislocata (A)

6a) Shell usually bearing many fine spiral cords, at least on early whorls . . . . Goniobasis virginica (A)
6b) Shell without fine spiral cords . . . . (7)


7a) Body whorl greater than 55% of shell length . . . . (8)
7b) Body whorl less than 55% of shell length . . . . (10)

8a) Animal orange with dark flecks . . . Goniobasis ebenum (S)
8b) Body of the animal primarily black . . . (9)

9a) Inhabits softwater rivers and streams, shell usually at least slightly carinate throughout, apex typically eroded . . . Goniobasis proxima (N, A)
9b) Inhabits hardwater streams, shell not carinate except in early whorls, apex not eroded . . . . Goniobasis simplex (N, T) 


10a) Shell usually with flat, unshouldered whorls, animal orange with black flecks . . . . . . (11)
10b) Shell with rounded whorls, animal not orange . . . Goniobasis semicarinata (N, A)


11a) Shell height greater than 3 times shell width . . . Goniobasis arachnoidea (T) 
11b) Shell height less than 3 times shell width . . . Goniobasis clavaeformis (T)