Taxonomy, life cycle, development, and habits of two new species of Allantonematidae (Nematoda) parasitic in drosophilid flies

Abstract

1. Two species of Allantonematidae were found parasitizing five of twelve species of Drosophila collected at Rothamsted Experimental Station, Harpenden, Herts, England.2. H. aoronymphium sp.nov. was found in 20·8 % of D. phalerata and 4·3 % of D. kuntzei examined. Parasitylenchus diplogenus sp.nov. was found in about 5 % of D. subobscura, D. obscura, and D. silvestris examined.3. The type species and taxonomy of the genus Parasitylenchus are discussed.4. The life history of H. aoronymphium is typical of most allantonematids except that the female is fertilized when she is a fourth-stage larva. P. diplogenus has two sexual generations per cycle.5. Both nematodes have a precocious development of the male and a retarded development of the female genital system. Both destroy host gonads.6. The specificity of the nematodes is not a result of dissimilar ovipositing habits of the hosts, but shows a similarity to the taxonomic assignment of the hosts to subgenera.