Orwellion gib. arizonense Click here for a larger view

Diagnosis.--Key characters: Ommatidial size coarse (Fig. 39b); prosternal process not planar, apex expanded (Fig. 18); mesal antennal spines present (Figs. 8b, 9b); pronotum with impunctate regions, without longitudinal rugosities or transverse ridges; femoral carinae absent; procoxal cavities closed laterally (Fig. 24); femoral apices rounded (Fig. 26); elytra without golden and silver pubescence; procoxal cavities open posteriorly (Fig. 18); tibial carinae present; pro- and mesofemora gradually enlarged (Fig. 37c); metafemora gradually enlarged or linear (Fig. 37c, d); shape of spine of antennomere three acute (Fig. 45a, b); antennomere three of males (and most females) about two-thirds length of pronotum (Fig. 46b); antennae without dense fringe of pubescence ventrally; lateral projections from mesosternum into mesocoxae absent (Fig. 20); body covered with recumbent pubescence (Fig. 13b); elytral apicolateral spines weak. Length: 12-17 mm.

Distribution and Diversity.--Southwestern United States to Costa Rica. Four species.

Discussion.--Orwellion occurs in the key near Protomallocera, although it is distantly related. Orwellion is closely related to Enaphalodes, Eustromula, Gymnospyra, and Parelaphidion (Figs. 50, 56), based on the implied weighting phylogenetic analysis.

Orwellion resembles species of Enaphalodes, Parelaphidion, and Trichophoroides. It differs from Enaphalodes and Parelaphidion in possessing differentiated dense patches of white pubescence posterior to the upper eye lobes. Orwellion differs from Trichophoroides in having antennomere three of males and most females about two-thirds length of pronotum and without dense fringe of pubescence ventrally.