Virginia Ictalurid Catfishes 
89 
18-21 (Blair et al. 1957); 18-24 (Trautman 1957); 19-23 (Eddy 1969); 18-22 
in key, 19-23 in text (Clay 1975). The larger ranges and lower extremes of 
these counts may have resulted from failure to count all anterior 
rudimentary rays in at least some of the material examined by these 
authors. Smith-Vaniz (1968) reported a count range similar to ours (21- 
26, X = 23). The gap in the “bony ridge” between the head and dorsal fin 
(a disjuncture between the supraoccipital and the anterior process of the 
first pterygiophore), reported in keys by Hubbs and Lagler (1958) and 
Clay (1975), was consistently present in /. catus. However, a disjuncture 
also occurs in juveniles of /. punctatus and /. furcatus. 
Until recently, anal ray counts were reported to have little overlap 
between 1. furcatus and /. punctatus (Trautman 1957; Blair et al. 1957; 
Pflieger 1975; and others). However, Clay (1975) reported anal ray count 
ranges to be 27-34 for /. furcatus and 23-29 for 7. punctatus and 
emphasized the need to consider anal fin shapes (Fig. 3F, G). An obvious 
character when present are the spots on young to adult /. punctatus, but 
adults often lack them. W. Ralph Taylor (pers. comm.) informed us of a 
difference in the gas bladders of L furcatus and I. punctatus; that of I. fur- 
catus has an elongate posterior extension and that of /. punctatus does 
not. The gas bladder difference is illustrated by Pflieger (1975). 
KEY TO VIRGINIA ICTALURIDS WITH AN ADNEXED ADIPOSE FIN 
1. Premaxillary tooth patch with posterolateral 
extensions (Fig. 3A); upper lobe caudal fin 
partially depigmented (varies in adults) Pylodictis olivaris. 
Premaxillary tooth patch without posterolateral 
extensions; upper lobe caudal fin not partly 
depigmented 2. 
2. Caudal fin deeply forked (Fig. 3F, G) 3. 
Caudal fin moderately forked to emarginate 
(Fig.3H,I) 4. 
3. Anal fin margin usually rounded (Fig. 3G); anal rays 
23-29; young to small adults often with spots Ictalurus punctatus. 
Anal fin margin straight (Fig. 3F); anal rays 27-34; 
never spotted I. furcatus. 
4. Caudal fin moderately forked (Fig. 3H); anal rays 
usually 22-24 (22-25) /. catus. 
Caudal fin emarginate (Fig. 31) 5. 
5. Dorsal fin with dark basal blotch (Fig. 3D); eye size 
moderate (flathead bullheads) 6. 
Dorsal fin without dark basal blotch (Fig. 3E); eye 
size small (typical bullheads) 7. 
6. Mental barbels usually without pigment (pigment may 
be present in large specimens on lateral barbels, rarely 
on medial); leading edge of maxillary barbels pale 
