Cremastocheilus constricticollis

One of about thirty-five species of myrmecophilous Cremastocheilus. The host ant is Myrmecocystus mexicanus.

Distribution
Arizona

Habitat
Common host is Myrmecocystus mexicanus.

Description
Medium sized, elytra moderately robust, pronotum slightly more than one-half as wide as elytra; thorax and elytra piceous, head and legs reddish. Head with vertex moderately densely punctate, punctures separated by about their own widths, front with transverse impression in front of eyes, front and impression clothed with golden pile, median carina prominent, glabrous dorsally, sides with pile behind and a tomentose patch on either side in front but behind reflexed clypeal margin; clypeus impunctate, as wide as head and strongly reflexed, median reflexed portion extending posteriorly and connecting with carina; mentum cupuliform, front and side margins evenly rounded, posterior margin medially produced into an acute point.