Cactodera eremica n. sp., Afenestrata africana (Luc et al., 1973) n. gen., n. comb., and an Emended Diagnosis of Sarisodera Wouts and Sher, 1971 (Heteroderidae)

Abstract

Systematic contributions to Heteroderidae include description of Cactodera eremica n. sp., an emended diagnosis of Sarisodera Wouts and Sher, 1971, and proposal of a new genus and new combination, Afenestrata africana (synonym Sarisodera africana Luc et al., 1973). Cactodera eremica, from the roots of shadscale in Utah, most closely resembles Cactodera thornei (Golden and Raski, 1977) but differs by the presence of a finely striated cuticle, a fine surface pattern on eggs, a shorter female stylet, distance of the DGO from the stylet, vulval slit, and smaller diameter ofcircumfenestra, as well as a shorter tail in second-stage juveniles. The response of the host to C. eremica is similar to other Heterodera sensu lato including a large syncytium with wall ingrowths. The diagnosis of Sarisodera is emended to exclude cysts, which do not form in the type species, S. hydrophila. Afenestrata africana differs from S. hydrophila by the formation of cysts, the dorsal position of the anus in females, the shorter stylet, and a pore-like phasmid opening in second-stage juveniles. In addition, the lip pattern of males and juveniles is characterized by a greater degree of fusion of lip parts, the host response is a syncytium (versus a single uninucleate giant cell in S. hydrophila), and the cuticle is thinner and lacks a D layer. Unlike Heterodera, the cyst of Afenestrata lacks fenestrae. Key words: comparative morphology, cyst nematodes, giant cell, Heterodera, histopathology, host response, scanning electron microscopy, taxonomy.