This is the male Philonicus rufipennis. It is generally a creekrunner and often takes damsels along these creeks. Note the marked orange and black leg coloration, the white mystax and the banding of the abdomen in this male with the elongate genitalic appendages. The male terminus from above makes a wide open circlet of black. This small genus is related to Machimus and in the past these genera and the old Tolmerus genus have been bounced around in the shrinking Asilus genus. We may have one other Philonicus which is limpidipennis but it is not proven in our state. It does occur in Oklahoma.

The female with very similar leg markings. Marked contrast between the pale abdomen and the dark terminal segments. Found together on the creek rocks in most clear streams in the Ozarks. Sometimes in very large numbers. I have never honestly seen Machimus species favoring the rocks of creeks. Most of those species prefer vegetation perches.

Then in TX and AZ is another genus in the Asilinae that is related to Machimus and Philonicus. We have not had one in AR. This is the female. They are Polacantha. The male has a tremendous terminal apparatus for their size and it is on the same slender abdomen. Note the terminal difference here from the above Philonicus female: shorter wings, longer terminal abdominal segments. TX has three species. I think this is P. grossa.