Pena Blanca Lake
Santa Cruz County, Arizona
Coordinates: 31.399676, -111.088883
Elevation: 3.869 ft
June 2, 2020
Size: 2.3 mm
Attracted to mercury vapor and ultraviolet lights
Determined by Salvador Vitanza
Confirmed by Matthew L. Gimmel who said: “This is a species of Stilbus in the S. apicalis group. One interesting thing about this group is that although the eastern species, which we refer to as S. apicalis proper, appears to be parthenogenic (i.e., all-female), there are several western forms with males, and it’s unclear whether any of these are conspecific with eastern S. apicalis. Incidentally, males can be recognized by a posteriorly-pointing tooth-like structure on the hind margin of abdominal ventrite 3. The tip of the aedeagus can also be seen peeking out behind ventrite 5. The y-shaped metaventral lines, appearing almost exclusively in this genus, are also clearly seen in this photo.”