no. 3602 CRAYFISHES — HOBBS, HOLT, AND WALTON 61 



112; with C. carolinus at 8, 22; with C. I. longulus at 9, 10, 12, 20-22, 

 25, 27, 29, 32-35, 37, 88-93, 112, 123, 124; and with C. sciotensis at 3, 

 5, 19, 44, 50, 54-56, 59, 66, and 106-109. 



Ostracod associates include -Aw. ancyla at stations 88, 89, 92, 93; As. 

 asceta and Dt. chalaza at 8, 22; Dn. ardis at 10, 12, 20, 21, 25, 27, 32, 

 33, 35. 37, 123, 124; Dn. ileata at all stations except 17, 27, 36, 39, 53, 

 68,87-93, 111, 112, 115, 118, 120, 121 ; Dn. scalis at 17, 39, 44, 68, 115; 

 Dn. truncata at 53-56, 69, 71, 87, 88, 90, 91, 93, 94, 111; Dt.jalcata at 

 87-93, 111, 112; Dt. suteri at 27, 33, 35, 124; E. internotalus at 35, 88, 

 90; E. kanaivhaensis at 44; and P. phyma at 3, 5, 24, and 44. 



Branchiubdellid associates include A. koronaeus at stations 14, 19, 

 29, 52, 69, 71, 77, 87-93, 98, 110-112, 125; B. illuminatus at 5, 16, 17, 

 19, 20, 22, 34, 44, 45, 48, 51, 59, 68, 76, 87, 115, 120-122, 125; C. 

 branchiophila at 20, 24, 29, 55, 66, 87-93, 112; C.Jallax at 3, 5, 24, 54- 

 56, 66, 71, 87-S9, 91, 92; C. heterognatha at 3, 5, 24, 28, 34, 45, 48, 66, 

 106, 122, 123, 125; C. holostoma at 10, 19-22, 25, 37; C. ingens at 5, 54; 

 P. alcicornus at 3, 5, 19, 24, 25, 66, 74, 76; Xd.jormosus at 10, 21, 88- 

 92, 112; and Xg. instabilius at 3, 5, 9, 12, 21, 22, 24, 37, 44, 46, 53, 54, 



60, 121, and 123. 



Genus Pterodrilus Moore, 1895 



Diagnosis. — Distinguished from Cambarincola by smaller size and 

 presence of dorsal projections on prosomites of at least one trunk 

 segment. 



Pterodrilus alcicornus Moore 



Figure 20 

 Pterodrilus alcicornus Moore, 1895a, p. 449. 



Diagnosis. — With fanlike and cylindrical processes on dorsum of 

 prosomites of segments in, iv, v, vin. 



Range. — Southern Appalachians from Virginia southward to 

 North Carolina and Tennessee (principally in the New and Tennessee 

 Rivers) . 



Specimens examined. — Approximately 125 specimens in 29 col- 

 lections from the following stations: 3-5, 15, 18, 19, 24, 25, 43, 58, 



61, 63-67, 70, 72-76, 79, 81, 86, 95, 97, 104, and 105. All but two of 

 these stations are in the New River drainage; stations 24 and 25 are 

 in the James (tributaries of Johns Creek) drainage. Elevations 

 range from 488 to 838 m. 



Hosts and associates. — Pterodrilus alcicornus was associated with 

 Cambarus b. bartonii at stations 3-5, 19, 24, 25, 63, 64, 66, 74, 76, 

 95, 97; with C. I. longulus at 25; and with C. sciotensis at 3, 5, 15, 18, 

 19, 43, 58, 61, 63-67, 70, 72, 73, 75, 79, 81, 86, 95, 97, 104, and 105. 



