dd. Thorax constricted in the middle or cephalad of the middle; anterior tarsi each three-segmented.
e. Apex of the scutellum narrow, without spines or with a single spine Reduviinæ
f. Antennæ inserted in the lateral or dorso-lateral margins of the head; antenniferous tubercles slightly projecting from the sides of the head; head produced strongly cephalad; ocelli at least as far apart as the eyes.
g. Antennæ inserted very near the apex of the head; segments one and three of the beak short, segment two nearly four times as long as segment one. R. prolixus. W. I. Rhodnius Stäl
gg. Antennæ inserted remote from the vertex of the head.
h. Body slightly hairy; pronotum distinctly constricted; angles distinct; anterior lobe four-tuberculate, with the middle tubercles large and conical. M. phyllosoma, large species the southwest. Meccus Stäl
hh. Body smooth, margin of the pronotum sinuous, scarcely constricted; anterior lobe lined with little tubercles. Conorhinus Lap.
i. Surface of the pronotum and prosternum more or less granular.
j. Eyes small, head black; body very narrow, a fifth as wide as long; beak reaches the middle of the prosternum. California. C. protractus
jj. Eyes large, head fuscous; body at least a fourth as wide as long. Southern species. C. rubrofasciatus