8U. 



Subfamily WILSONBIATINAE Chitwood, 1951 

 (Key to the genera from Cobb, 1935) 



1. Terminal bulb valved 2 



Terminal bulb not valved Anonchus Cobb, 1913 



2. Lips 6, distinct, revolute; striae fine; amphids semicircular 



Anthonema Cobb, I906 



Lips not revolute; head with dorso-ventral bladders; striae coarse; 

 amphids roimd 3 



3. Cephalic appendages elaborately palmate Wilsonema Cobb, 1913 



Cephalic appendages forming a closed, striated dome or cupola 

 Bitholinema de Coninck, 1931 



Subfamily PLECTINAE Micoletzky, 1922 

 (Key to the genera) 



1. Esopha;^s short, cardia extremely long. . . Paranlectonema Strand, 1936 

 Esophagus not usually short, cardia moderate 2 



2. Stoma very short conoid; esophagus very long. . Chronogaster Cobb, 1913 P.&h 

 Stoma not very short, esophagus not unusually long 3 



3. Male with conoid supplementary organs 



Anaplectus de Coninck & Stekhoven, 1933 



Male with papilloid supplementary organs Plectus Bastian, 1865 



Genus Chronogaster Cobb, 1913 

 (Key to the species modified from Andrassy, 1958) 



1. Longitudinal striations present . . 2 



Longitudinal striations absent 3 



2. Tail terminus with 3 small appendages . . . magnificus Andrassy, 1956 

 Tail terminus without appendages alatum Gerlach, 195U 



3. Tail terminus with h appendages 



longicollis (Daday, 1899) Andrassy, 1958 



Tail terminus with only 1 appendage U 



I4. Body extremely thin (a^almost 100); mouth cavity symmetrically 



constricted, funnel-shaped subtilis Andrassy, 1958 



Body not as thin (asbelow 70); mouth cavity prismatoid 5 



5. Body cavity with numerous distinct crystals; lateral glands large, 



striking typicus (de Man, 1921) de Coninck, 1935 



Body cavity without crystals; lateral glands indistinct 6 



6, Amphid situated posterior to the mouth cavity, soiral; tail shorter 



than 1/10 the body length boettgeri Kischke, 1956 



Amphid situated at the level of the mouth cavity, buckle-shaped; tail 

 very long 



