The male G. ventralis moth is displayed here to have a predominantly black body except for the bottom of the abdomen and the head area -- save for the eyes -- which are an orange color. Its two antennae are marked by miniature teeth-like structures. Quite typical of a moth, it was resting with its wings closed, and wasn't even concerned about my slowly approaching behemoth of a camera lens. Update: finally figured out the species -- it is indeed Gnamptonychia ventralis, except we did not know that it was a male until the folks at Bug Guide set me straight. Males have an orange underside and black on top of the abdomen, whereas the females have the abdomen tip orange while the rest of its body, aside from the head (not including the eyes), is black.
Preferring lower altitudes of no less than 6,000 feet, and not too widespread; only two were spotted throughout the whole mountain-range and for the duration of the 10-hour hike. Thanks to the Butterflies and Moths of North America page, it is known that they only have been sighted in the southeastern Arizona mountains and one lone stray spot in central Texas.
From abdomen to head, it is under 4 centimeters. Found exactly at 7:15 AM. Compare with a female's coloration here: http://www.lepbarcoding.org/northamerica... The first thing I thought of when I saw this moth was "Halloween come early?" :)