New Species and a Key to North American Solierella in the Inermis Group (Hymenoptera: Sphecidae: Larrinae: Miscophini)

The inermis group of Solierella is named after the first known North American species, "Nysson? inerme" Cresson 1872, and is distinguished by the forewing venation. In addition to the petiolate forewing second submarginal cell common to the tribe, the second recurrent vein curves sharply backward to end at about the middle of the second submarginal cell (fig. 23). Also, males of North American species have a bi-colored antenna: black marked with orange, yellow or whitish (figs. 1-16). The extent of the pale antennal markings in the male, together with conformation of the clypeus, are species diagnostic. On the other hand, female characters are few and determinations are best made by association with males. Female characters of some value lie in the clypeus, vertex, and ridging laterally on the propodeum. A summary of group characters is given below in order to simplify descriptions of the 10 new species. The total number of known species of this group from North America is now 16. Additional ones will likely be found, and several more occur in South America. Most of those from the latter area appear to have the male antenna all dark or nearly so. Curators or Collection Managers of several institutions have been particularly helpful in the present study. These are: R. W. Brooks, University of Kansas; J. A. Chemsak, University of California, Berkeley; S. I. Frommer, University of California, Riverside; T. Griswold, Utah State University (USDA); E. R. Hoebeke, Cornell University; A. W. Hook, St. Edwards University, Austin, Texas; L. S. Kimsey, University of California, DAVIS; L. Masner, Canadian National Collection; A. S. Menke, U.S. National Museum; W. J. Pulawski, California Academy of Sciences, SAN FRANCISCO; E.