Strelkovimermis acuticauda n. sp. and Strelkovimermis buccalis n. sp. (Nematoda:Mermithidae) from adult chironomids (Diptera:Chironomidae) from Lake Itasca, Minnesota.

Specimens of 2 mermithid species were obtained from adults of undetermined species of chironomids emerging from Lake Itasca (Clearwater County), Minnesota. Both species have the characteristics of species in the genus Strelkovimermis. The new species are distinguishable from one another and from the 8 currently accepted species in the genus by their small size, shape of the posterior end, length of the buccal funnel, length of the cephalic papillae, location of the mouth, and morphology of the spicule region and vagina. Strelkovimrmis acuticauda n. sp. is unique in possessing an acute posterior end, an auxiliary protractor muscle, and a relatively long vagina, whereas Strelkovimermis buccalis n. sp. is distinguishable from other Strelkovimermis species by its thick cuticle and exceptionally long buccal funnel. The significance of the tail muscles is emphasized as a taxonomic feature to be used in describing future species of Strelkovimermis. A key to the 10 species of Strelkovimermis is provided.