38 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 123 



Ostracods with which it was associated include Dn. ileata at all 

 stations except 13, 27, 30; Dt. suteri and E. internotalus at 30, 31, 35; 

 Dt. suteri at 27, 33, 124; and E. internotalus at 23. 



Branchiobdellid associates include C. philadelphica at stations 10, 

 12, 20, 21, 25, 27, 32, 33, 35, 37, 123, 124; C. holostoma at 10, 11, 13, 

 20, 21, 23, 25, 37; Xg. instabilius at 11-13, 21, 37, 123; Xd. jformosus 

 at 10, 21; A. koronaeus at 30; B. illuminatus and C. branchiophila at 

 20; C. heterognatha at 123; and P. alcicornus at 25. 



Donnaldsoncythere ileata Hobbs and Walton 



Figure 8c 

 Donnaldsoncythere ileata Hobbs and Walton, 1963, pp. 364, 368, figs. 11-15, 23. 



Diagnosis. — Copulatory complex with peniferum terminating 

 ventrally in rounded extension, with posterior thickened border; 

 anterior border always rounded; clasping apparatus with proximal 

 shaft portion almost straight and distal third directed at angle of 

 90° to 135° to shaft; internal border of distal fourth with two teeth 

 and terminal margin with four or five serrations. 



Range. — Tributaries of the James, New, and Roanoke Rivers in 

 Craig, Giles, and Montgomery Counties, Va., and Monroe County, 

 W.Va. 



Specimens examined. — Approximately 3000 specimens from 100 

 collections from the following stations: 3-12, 14-16, 18-26, 28, 29, 

 31-35, 37, 43-48, 50-52, 54-67, 69, 71-77, 79-81, 84, 86, 94-99, 102, 

 104-110, 113, 116, 117, 119, and 122-126, at elevations of 415 to 899 m. 



Hosts and associates. — In one or more stations, it was associated 

 with every species of crayfish in the area except C. carolinus. It 

 was with C. b. bartonii at stations 3-10, 12, 14, 16, 19, 21-26, 28, 29, 

 32, 34, 35, 37, 44-48, 50-52, 54, 57, 59, 60, 63, 64, 66, 69, 71, 74, 76, 

 77, 94-99, 107, 108, 110, 113, 117, 119, 122-125; with C. sciotensis 

 at 3, 5, 15, 18, 19, 43, 44, 50, 54-59, 61-67, 72, 73, 75, 79-81, 84, 86, 

 95-97, 102, 104-109, 116, 126; with C. I. longulus at 6, 7, 9-12, 20-23, 

 25, 29, 31-35, 37, 123, 124; with O. acuminatus at 20, 29, 31-33, 35; 

 and with O. juvenilis at 7. 



Although in 52 stations Dn. ileata was the only ostracod present, 

 it was found with P. phyma at stations 3, 5, 7, 24, 44, 64; with E. 

 internotalus at 23, 31, 35; with Dt. suteri at 31, 33, 35, 124; with Dt. 

 daphnioides at 72, 73, 75, 79-81, 116; with Dn. ardis 10-12, 20, 21, 

 23, 25, 31-33, 35, 37, 123, and 124; with Dn. truncata at 54-57, 69, 

 71, 94; with Dn. scalis at 7, 44; and with E. kanawhaensis at 44, and 

 126. 



Branchiobdellid associates include all 12 species known from the 





