127. 



Genus Nygolaimus Cobb, 1913 

 (Key to the species modified from Thome, 1939) 



1. Length more than 7 mm husmanni Keyl, 195U 



Length less than U.5 mm 2 



2. Pharynx without denticles ........... 3 



Pnarynx with denticles 28 



3. Terminus blunt, rounded .... k 



Terminus acute or subacute 2$ 



k. Lip region set off by constriction 5 



Lip region not set off, continuous ... ........ 17 



5. Tooth hollow less than half its length, very slender 6 



Tooth hollow almost to apex .,, 7 



6. Only females known vulgaris Thome, 1930 



Bisexual species bisexualis Thome, 1930 



7'. Death position spiraled, 1^-2 times spiralis. Loos, 19i|6 



Death position not spiraled 8 



8. Length 2.1 - 2,7 mm; V= Ul -h^% cuniculus Altherr, 1950 



Length above or below 2.1 - 2.7 mmj V= h^% or more. ........ 9 



9. Body length 2.0 mm or less ...10 



Body length near 3.0 mm or more . , 16 



10. Lip region one-third as high as wide 11 



Lip region one-half or more as high as wide 12 



11. Tail convex- conoid; V= 66^. pachydermatus Cobb, 1913 



Tail conoid, ventrally arcuate; V= S2%. . . . plan-posae Altherr, 1958 



12. Tail swollen, clavate, hemispherical. . , clavicaudatus Altherr, 1953 

 Tail not swollen, conoid „ , 13 



13. Tail dorsally- convex, slightly ventrally arcuate 



. paramphigonicus Altherr, 1950 



Tail uniformly convex-conoid lU 



lU, Tail obtusely convex- conoid, with 1 pair of caudal papillae .... 15 

 Tail uniformly conoid, with 2 pairs of caudal papillae 

 paulbuchneri Meyl, 1956 



15. Pharynx three times as deep as lip region tenuis Thome, 1930 



Pharynx twice as deep as lip region amphigoniaus Thorne, 1930 



16, Tail symmetrically conoid rounded . obtusus Thome, 1930 



Tail dorsally convex- conoid , . brachyurus (de Man, 1880) Thorne, 1930 



