Ironeus duplex Click here for a larger view

Diagnosis.--Key characters: Eyes small, less than 50% size of head as viewed laterally with finely-faceted ommatidia (Fig. 39a); transverse ridges on pronotal disc absent; raised ivory calli on elytra absent; femoral carinae absent; tibial carinae present (Fig. 22); femoral apices rounded (Fig. 26); lateral projections into mesocoxae from mesosternum present (Fig. 21); posterior procoxal cavities open (Fig. 18); median pronotal callus absent; flying hairs absent from elytra; elytra not maculate with large pale spots (usually unicolorous); elytra varying from truncate to weakly spinose at apices (Fig. 41b-d); elytral apices not narrowed or elongated apically; femora gradually enlarged (Fig. 37c); third antennomere only about 1.5 times as long as fourth; bottom margin of metepisternum angling up and intersecting elytra towards posterior end (Fig. 32). Length: 7-17 mm.

Distribution and Diversity.--México to Panamá, Bolivia, Venezuela. Three species. (I. submetallicus is transferred to Stizocera).

Discussion.--Ironeus is very closely related to Stenosphenus, and the two genera are sister groups based on the analysis (Figs. 50-55). Ironeus submetallicus has been transferred to Stizocera based on pronotal and ommatidial characters which they share. Tropimerus is probably very closely related to Ironeus and Stenosphenus, and when specimens are available for detailed character analysis, they should be included.

Ironeus differs from Tropimerus in lacking mesofemoral carinae. Ironeus differs from Stenosphenus in the exposure of the bottom margin of the metepisternum. In Ironeus, the bottom margin angles up posteriorly and intersects the elytra; in Stenosphenus the bottom margin is approximately parallel to the elytron above it.