120. 



17 ♦ Body length imder 2.0 mm .18 



Body length near 3,0 mm or over ,....,.,,..,,.,... 22 



13. Two glandular organs present near base of neck. . . teres Thorne, 1930 

 Glandular organs not present 19 



19. Ventromedian supplements one only .... borborophilus (de Man, 1876) 

 Ventromedian supplements three or more 20 



20. Lip region hemispheroid .... . laevis Thorne, 1939 



Lip region more truncate 21 



21. Cephalic papillae distinct, projecting kaburaki Imamura, 1931 



Cephalic papillae continuous, obscure .... thomei Schneider, 1937 



22. Spicula curved proximally rapax Thome, 1939 



Spicula not curved proximally 23 



23. Depth of pharynx about four times width of lip region 



.... aouaticus Thorne, 1930 



Depth of pharynx less than three times width of lip region. . . . . 2U 



2U. Head region sub cylindrical shadini FiliD.iev, 1928 



Head region more conoid, tapering , . ferox Thorne, 1930 



25. Tooth half as long as width of lip region . acuticaudatus Thorne, 1930 

 Tooth about as long as width of lip region. 26 



26. Terminus very acute .......... . curvistilis (Stefanski, 1923) 



Terminus subacute .......... 27 



27. Tail length about twice anal body diameter. . . . dubius Thome, 1930 

 Tail length about three times anal body diameter 

 hartingii (de Man, I88O) Thorne, 1930 



28. Body length under 3.0 mm ..... menzeli Micoletsky, 1925 



Body length over i|.0 mm .denticulatus Cobb, 1922 



