NEW AMERICAN CRYPTOPID GENUS — CRABILL 3 



nous strip; second, its apical claw long and acuminate, its dorsal 

 edge pectinate, its ventral edge undissected. Prehensorial segment: 

 Prosternum with anterior margin plain, without sclerotized ridges or 

 plates; ventrally without, dorsally with a short pair of sinuous chitin- 

 lines. Prehensors: Spinous processes and denticles absent; poison 

 calyx in trochanteroprefemur, robust and elongate; tarsungula of 

 normal size and configuration (as in Kethops). Tergites: First with 

 omegoid sutural pattern plus posterior paramedian sutures and 

 anterior cervical suture; 2-22 each with complete paramedian 

 sutures; other sutures absent; 23 without sutures or sulci. Sternites: 

 1-22 each with a shallow midlongitudinal sulcus; submarginal and 

 cross-sulci both apparently absent. Spiracles: Not operculate; on 

 pedal segments 3, 5, 8, 10, 12, 14, 16, 18, 20, and 22. Legs: 1-21 each 

 long and very thin, each tarsus essentially divided by an incomplete 

 ventro bilateral suture, none with a dorsal condyle; 22 very long and 

 thin, tarsus with a dorsal condyle and completely bipartite; 23 the leg 

 cryptopiform, the tarsus with condyle, the prefemur, femur, tibia, and 

 1st tarsus each with from one to many ventrally ankylosed mucrones 

 (see note 3, p. 13) ; the pre tarsus unlike those preceding, ^vithout acces- 

 sory claws. Coxopleuron: Porigerous; with a ventroposterior short, 

 thin, acute spinous process. 



Type species: Thalkethops grallatrix, new species (by present 

 designation and monotypy). 



Thalkethops grallatrix, new species 



Figures 1-5, 7, 9-11, 13-16 



Holotype probably female. New Mexico, Eddy County, Carlsbad 

 Cave (see note 4, p. 14) ; Dixon Freeland and Thomas Ela, August 31, 

 1957, USNM 2505. 



Body length 34.5 mm. General color: Antennae, head, prehensors, 

 and ultimate legs with associated segment pale yellow; tergites, 

 sternites, and other legs yellowish-white to whitish and translucent 

 to transparent, the underlying musculature plainly disclosed. 



Antennae: Each 15 mm. long, each with 17 articles; very pale 

 yellow. From dorsal aspect articles 3-17 conspicuously longer than 

 wide (e.g., 4th, length: width = 3.4 mm.: 1.0 mm.; 10th, 1: w = 3.0: 

 0.6 ; see figs. 5-6) . Articles 1-3 each sparsely clothed with longer setae, 

 4 partly clothed with finer denser setae, 5-17 densely finely setose. 



Cephalic plate : Yellowish, shining, 2.0 mm. long, 2.2 mm. at greatest 

 width; very sparsely invested with minute setae. Posterior corners 

 markedly rounded, sides straight as far as anterolateral angles, there- 

 after converging to form the anterior apex, the apex centrally in- 

 dented and bisected by a short distinct suture. Paramedian sutures 



