Characteristics & Similar species
Heteromeringia nigripes and the closely related H. nitida are similar in appearance, but differ slightly in colour and male genitalia. Heteromeringia nigripes has a yellow fore coxa (white in H. nitida), brown mid and hind coxae (brown in Mexican H. nitida), a brown or brownish pedicel (yellow in H. nitida excluding specimens from Mexico) and slightly different wing venation (see key). Both of these species differ from other North American Heteromeringia in having only a single pair of vibrissae, a small pilose disc on the male anepisternum and no additional upcurved posterodorsal anepisternal bristle (just before the wing base).

A third species closely resembling these two, Heteromeringia fumipennis, is expected to occur in Florida and/or eastern Texas but has not yet been found in North America. It is a common, widespread neotropical species characterized by a darkly-clouded wing that becomes clearer towards vein M, and male cerci that are thin and entirely united along their length.

Distribution
Most records of Heteromeringia nigripes are from the western United States, and while there are some records from New Jersey and Virginia, the only Heteromeringia encountered with any frequency in the east is H. nitida. A number of H. nigripes specimens have also been collected in southern Brazil, Costa Rica, Honduras and Mexico, mostly at high altitudes.

Biology
In the United States, specimens have been collected near rivers, meadows and in association with ponderosa pine.