lat-rio. K:3 



KKY TO TllF, .Sri'.GIK;". 01'' TlfF, GKMUr. XJIIIl Ml'.HA COHD, 1913 

 (Krom T,(irdpllo, 19Ip!?1 



As several ne\< forms of "dagr^'V nematodes" have been described since the 

 publication of Thome's mono):raph (1939), the writer organized the follow- 

 ing key for the separation -of the species known to date. Only female 

 characters were used in the key, as the Xiphinema males are frequently 

 rare and unknown in some species. Unfortunately, it was not possible to 

 place in the key the species described by Schuurmans Stekhoven in 1931 

 (X. brevicaudat\im , X. effilatum , and X. digiticaudatum ) as they were 

 based on larvae. 



In previous publications, the writer emended the names of three species 

 of the genus, because they were established either by a printing error 

 or a lapsus calami . The writer's procedure was based on the 19th article 

 of the International Rules of Zoological Nomenclature ( apud Amaral, 1950). 

 These three forms are: X. grande Steiner, 19lUj X. pratense Loos, 19h9j 

 and X. insigne Loos, 19U9; formerly referred to as X. grandis , X. pra - 

 tensis , and J^. insignis . ) 



1. Ovary one 2 



Ovaries two 5 



2. Tail rounded ajid short X. ensiculif erum (Cobb, 1893) Thorne, 1939 



Tail elongated, conoid or digitate 3 



3. Two pairs of caudal papillae present h 



Three pairs of caudal papillae present X. radicicola Goodey, 1936 



II.. Tail elongate, amphids narrow and long X. chambers! Thorne, 1939 



Tail distinctly digitate, amphids iiride and short 



X. brasiliense Lordello, 1951 



5. Tail short and rounded 6 



Tail elongate, conoid, subconoid or digitate 9 



6. Lip region set off by constriction 7 



Iiip rcf^lon continuous o 



