The genus Monodontomerus Westwood, 1833 (Hymenoptera, Torymidae) is distributed throughout the Globe, mostly in the Holarctic Region. Members of this genus are prolific parasitoids of pollinators and some are economically important. The New World fauna includes 25 described species and was revised 25 years ago.
Two new species of parasitoid wasp, Monodontomerus rhinokopia Chitty and Duran sp. nov. and Monodontomerus verdigris Chitty and Duran sp. nov. (Torymidae, Monodontomerinae) are described from the Pacific Northwest region of North America. Monodontomerus rhinokopia may be differentiated from other species in the genus by simultaneously possessing the following combination of characteristics: a face not bulging in profile, malar sulcus well defined and straight (Fig. 5), F1-F7 subquadrate (Fig. 7), longitudinal irregular carinae on its dorsellum (Fig. 8), sculpture of mesepimeron confined to ventral margin (Fig. 5), apical rim of scutellum produced posteriorly and not emarginate, costal cell on anterior margin above with row in distal half and lacking setae basally, dorsal admarginal setae reaching both marginal vein and parastigma (Fig. 6) and Mt1 reticulately sculptured dorsally. Monodontomerus verdigris may be differentiated from other members of the genus by simultaneously possessing the following characteristics: F1-F7 subquadrate (Fig. 3), striation in the anterodorsal corner of the mesepimeron which does not reach transepimeral sulcus (Fig. 1), carina of dorsellum which splits into two distinct carinae that form an open “V” (Fig. 4), median depression of propodeum narrowly triangular to nucha which it intercepts with nearly parallel lateral margins, a projecting rim of the scutellum which is not emarginated and a reticulately textured Mt1 (Fig. 2). A revised key to the New World species of Monodontomerus has been created to enable identification of these species.