40 U.S. NATIONAL MUSEUM BULLETIN 2 59 



Caverns is one of the largest caves in the northern Shenandoah 

 Valley and has been open commercially to tourists since 1946. 



Distribution and ecology. — 'This species is pesently known 

 from four caves developed in lower Paleozoic limestones, which 

 crop out along the Appalachian Valley floor just west of the Blue 

 Ridge Mountains. The range extends from Needy Cave in southern 

 Franklin Co., Pa., south-southwest to Skyline Caverns in central 

 Warren Co., Va., and covers an approximate linear distance of 65 

 to 70 miles. 



More than 50 percent of the collections made to date have been 

 from shallow cave pools. Although no ovigerous females have yet 

 been collected, a number of females ranging in size from 10.00 to 

 18.00 mm had well-developed brood plates, indicating, as mentioned 

 above, that sexual maturity may be reached between 10.00 and 

 11.00 mm in at least one population. The largest females (18.00 mm) 

 were taken from a large silt and gravel-bottom pool in Dam Number 

 4 Cave. Smaller females (up to 12.50 mm) were taken from much 

 smaller pools in Skyline Caverns. 



Stygonectes conradi, new species 



Figure 8 



Material examined 



VIRGINIA. — Bath Co.: Breathing Cave, holotype (USNM) and paratype female, 

 L. G. Conrad, Sept. 3, 1961. (Holotype, partially on a slide mount; paratype 

 temporarily in JRH.) 



Diagnosis. — Easily distinguished from S. gracilipes, to which it 

 is closely allied, by less elongate appendages, fewer spines on posterior 

 angle of 1st gnathopodal propod, longer dactyl claws of both gnatho- 

 pods, fewer setae on posterior margins of abdominal side plates, 

 larger and more spinose ramus of uropod 3, fewer lateral spines on 

 the telson, and smaller size. Largest female, 8.25 mm; male unknown. 



Female (holotype). — Antenna 1 about 50 percent as long as body, 

 about twice as long as antenna 2 ; primary flagellum with 17 segments. 

 Antenna 2, flagellum of 6 segments. Palpal segment 3 of mandible 

 rather stout, with 6 or 7 long setae; palpal segment 2 with about 

 6 setae. Maxilla 1, inner plate with 8 plumose setae apically. 

 Maxilla 2, inner plate with 8 long, obhquely placed, plumose setae. 

 MaxiUiped, outer plate reaching beyond apex of 1st palpal segment. 

 Inner lobes of lower lip small. 



Gnathopod 1 : propod palmar margin slightly concave, oblique, 

 armed with a double row of about 9 spine teeth; posterior angle with 

 4 large, unequal spines on outside, 5 smaller spines on mside; posterior 

 margin without setae; lateral setae few in number, mostly singly 

 inserted; dactyl claw long. Gnathopod 2: propod palmar margin 



