2 NEW SPECIES OF IMAGOCIDAL HYDROMERMIS (NEMATODA, MERMITHIDAE) FROM ENDOCHIRONOMUS SUBTENDENS (TOWNES) (DIPTERA, CHIRONOMIDAE)

Hydromermis viridis n. sp. and Hydromermis gastroviridis n. sp. are de scribed from June and August emerging images, respectively, of Endochi ronomus subtendens (Townes) in Lake Itasca, Clearwater County, Minneso ta. The position of the mouth, shape of the posterior end, structure a nd size of the spicule, absence of an excretory pore, arrangement of m ale tail musculature, and measurements separate the new species from o ther species of Hydromermis as well as from one another. The 2 species are placed in the genus Hydromermis though having a rounded tail and only 6 hypodermal cords at midbody. An anomalous double vagina conditi on is reported in H. viridis.