8 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 119 



and horizontal rami, the former one- third longer than latter; extensions 

 of rami forming an angle of approximately 80° to 85°; internal and 

 external borders of vertical ramus and external border of horizontal 

 ramus entire; internal border of horizontal ramus with two teeth, one 

 just proximal to midlength and the other subapical; apex with four 

 denticles. 



Type-species. — Thermastrocythere harti, new species. 



Remarks. — The name Thermastrocythere is derived from the Greek 

 depjiaaTpis, meaning tongs or pincers, referring to the forcipate 

 appearance of the ventral portion of the peniferum. 



Thermastrocythere harti, new species 



Figures 2e-g 



Male. — Eye present. Shell (fig. 2e) with highest portion slightly 

 posterior to midlength and with dorsal margin more gently tapering 

 posteriorly than anteriorly; ventral margin of shell entu-e; submarginal 

 setae present anteriorly, posteriorly, and ventrally but absent dorsaUy, 

 anterior and anteroventral setae closer together than posterior and 

 postero ventral ones. Range of shell size of 10 specimens recorded 

 in table 1. 



Copulatory complex (figs. 2J, g) as described in the diagnosis. In 

 addition, dorsal finger slender with tip of apical seta reaching level of 

 base of penis; ventral finger with moderate curve near base and a less 

 prominent one a short distance proximal to base of terminal seta. 



Female. — Female unknown. 



Type-locality, range, and hosts. — Cache Creek at White Wolf 

 Crossing, Fort Sill, Comanche County, Okla., on Orconectes nais 

 (Faxon). 



Additional localities include: Six Mile Creek near Waunakee, Dane 

 County, Wis., on Orconectes p. proinnquus (Girard) and 0. mrilis 

 (Hagen): McSpadin Falls, 10 miles northeast of Talequah on Route 

 10, Cherokee County, Okla., on Orconectes meeki hrevis WilHams, 0. 

 nana Williams, and 0. neglectus neglectus (Faxon); small stream, 13 

 miles west of Madison, Dane County, Wis., on 0. p. propinquus and 

 0. virilis; Yahara River near Sun Prairie where it crosses Route 19, 

 Dane County, Wis., on 0. p. propinquus and in association with 

 Entocythere camharia Marshall; White Pines State Forest, Ogle County, 

 111., on 0. virilis; and 5.9 miles west of Eyota on Route 14, Olmsted 

 County, Minn., on Cambarus d. diogenes Girard and 0. virilis, in 

 association with Bhadinocy there serrata (Hoff). 



Types. — The holotypic male and two paratypic males are deposited 

 in the U.S. National Museum (nos. 111258 and 111259). Paratypes 



