Ecology and systematics of the Mononchid nematodes from wood- and grassland areas in wet temperate climate. II. The genus Prionchulus Cobb, 1916

In: Revue de Nématologie, 1984, 7 (3), pp.215-225. The validity of the characters used to separate the two related species Prionchulus muscorum (Dujardin, 1845) Wu & Hoeppli, 1929 and P. punctatus (Cobb, 1917) Andrássy, 1958 was studied in a large collection of Prionchulus specimens. Until now, only qualitative criteria were used, namely the shape of the denticulate subventral ridges and the structure of the outer layer of the eggshell. A correspondence analysis has shown that other characters,such as the size of the buccal cavity and the position of the tip of the dorsal tooth are more reliable because they can be quantitatively and objectively interpreted. After a detailed study of those characters new diagnoses were proposed for the two species. For any identification, the size of the buccal cavity expressed as a function d, of its length and width and the position of the apex of the dorsal tooth in relation to d, has to be considered first; then the structure of the outer layer of the egg-shell and the aspect of its margin and qualitative characters such as the shape of the buccal cavity, the shape of the denticulate subventral ridge and the shape of the tail, can be used to precise the identification.