NEW AMERICAN CRYPTOPID GENUS CRABILL 9 



key, the North American distribution of each genus is briefly sum- 

 marized, and mention is made of the more important species. To the 

 best of my knowledge, a similar treatment devoted to the genera 

 represented in North America has not appeared in print since 1893, a 

 span of years characterized by the steady accumulation of distribu- 

 tional information as well as by significant revisionary activity, 

 la. With four ocelli on each side of the cephalic plate . . Scolopendbidae (2) 

 16. Without ocelli, the ocellar positions either concolorous with the remainder 

 of the cephalic plate or unpigmented and contrasting with the deeply- 

 colored environs Cryptopidae (3) 



2a. Spiracles operculate, i.e., each divided into an inner and an outer atrium 



by an internal and essentially tripartite valve . . . Scolopendrinab (5) 



26. Spiracles not operculate, i.e., each spiracular atrium fully exposed, none 



with an internal valvular partition Otostiqminab (7) 



3a. With 21 pairs of legs and pedal segments 4 



36. With 23 pairs of legs and pedal segments .... Scolopocrtptopinae (8) 



4a. Anterior margin of prosternum with a pair of elongate, coarsely toothed 



plates. Cephalic plate with prominent eyespots in the ocellar positions. 



Ultimate pedal segment conspicuously elongate; ultimate legs extremely 



heavy, robust Theatopinae, genus Theatops 



46, Anterior margin of prosternum without such toothed plates. Cephalic 

 plate without eyespots. Ultimate pedal segment of normal proportions. 

 Ultimate legs only slightly heavier than penults . . . Cryptopinae (12) 

 5c. First or proximotarsi of the first 15 to 20 pairs of legs each with a promi- 

 nent ventrodistal spur 6 



56. No proximotarsus with a ventrodistal spur .... Genus Hemiscolopendra 

 6a. Ultimate pretarsus basally with two accessory claws . . Genus Scolopendra 

 66. Ultimate pretarsus without accessory claws .... Genus Arthrorhabdus 

 7a. Seventh pedal segment without a pair of spiracles . Genus Otostigmus t 

 76. Seventh pedal segment with a pair of spiracles. Trochanteroprefemur of 



prehensor with a prominent inner spinous process Genus Rhysida 



7c. Seventh pedal segment with a pair of spiracles. Trochanteroprefemur of 

 prehensor without an inner spinous process . . . Genus Ethomostigmus f 

 8a. Seventh pedal segment with a pair of spiracles (see note 2, p. 13) . Ultimate 

 second tarsus either subdivided into many pseudosegments or un- 

 divided ^ 



86. Seventh pedal segment normally without a pair of spiracles. Ultimate 



second tarsus undivided 10 



9a. First pedal tergite often with an omegoid sutural pattern, always with pos- 

 terior paramedian sutures, complete or abortive. Ultimate second tarsus 



divided into pseudosegments Genus Newportia t 



96. First pedal tergite never with an omegoid sutural pattern, normally without 

 paramedian sutures or fragments thereof. Ultimate second Tarsus un- 

 divided Genus Dinocryptops 



(formerly Scolopocryptops; see note 2, p. 13) 



lOo. Prosternal anterior margin with a pair of low dark, heavily sclerotized 



ridges. Trochanteroprefemur distally with a prominent inner spinous 



process Genus Scolopocryptops 



(formerly Otocryptops; see note 2, p. 13) 

 106. Prosternal anterior margin unadorned, without dark, well sclerotized ridges. 

 Trochanteroprefemur without an inner distal spinous process .... 11 

 -59 2 



