Procloeon nelsoni, new species, and P. distinctum, new species, are describ
ed from larvae and from male and female adults. Both species were collected
from cool, alkaline waters of creeks and rivers in the hill country region
of Texas. Procloeon nelsoni is most closely related to P. diabolum, also r
ecently described from Texas, and probably represents a sister species. Pro
cloeon distinctum is similar in both the larval and adult male stage to P.
rubropictum, and probably represents a sister species.