Paraboreochlus stahli sp. n., a New Species of Podonominae (Diptera: Chironomidae) from the Nearctic

Paraboreochlus stahli sp. n. is described from collections in small streams of northwestern Pennsylvania, U.S.A. The larva (presumed), pupa, female (partial) and male are discussed and illustrated. P. stahli is only the second species known for the genus and is the first described species of Paraboreochlus from outside the Palaearctic. A differential diagnosis for P. stahli and P. minutissimus (Strobl) Edwards indicates distinct differences for the larva, pupa and male of these two species. The partial description of the female of P. stahli is the first for the genus. A comparison, based on a limited number of characters, of P. stahli and P. minutissimus with the Cretaceous chironomids Libanochlites neocomicus Brundin (female only) and the unnamed male of Schlee and Glockner (1978) suggests the following: 1) P. stahli and P. minutissimus are plesiomorphic to L. neocomicus, 2) P. stahli is plesiomorphic to P. minutissimus, 3) P. stahli closely resembles (except for the hypopygium) the Cretaceous male of Schlee and Glockner (1978) which, in turn, appears to be plesiomorphic to L. neocomicus. Additional collections of unassociated whole pupae and/or pupal exuviae from other small streams in western Pennsylvania and the Ozarkian Plateau region of southeastern Kansas indicate that the genus Paraboreochlus is widespread in North America.