Orconectes saxatilis (Bouchard and Bouchard)

Map [dots indicate Ouachita National Forest collection sites]

Recognition Characters: Rostrum with marginal spines. Areola 6.0 to 9.3 times longer than broad, constituting 28.7 to 29.9 percent of the total length of the carapace and with three punctations across the narrowest part. No cervical spines or tubercles. Hepatic spines absent; branchiostegal spine small and acute. Antennal scale longer than broad, broadest slightly distal to midlength. Chela with two subserrate rows of tubercles over the dorsomesial part of the palm. Scattered smaller tubercles over the dorsomesial half of the palm. Small setal tufts over the entire dorsal surface. Moderately well developed longitudinal ridges on the dorsal surface of finger. Hook on ischium of third pereiopod of first form male overreaching basioischial articulation. Male gonopod with central projection corneous, tapering and reaching basis of first pair of pereiopods when abdomen flexed. Shoulder present on cephalic surface; mesial process slightly shorter, non-corneous, with distal end curved mesiad.

Coloration: Both the cephalothorax and abdomen are concolorous sienna. The branchiostegites and hepatic region is lighter. The caudal edge of cephalothorox has a prominent dark brown band while the caudal edges of the abdominal terga have a narrow red margination. A pair of dark vermiculated blotches occur anterior to the cervical groove attachment of mandibular muscles. The ventral aspects of cephalothorax and abdomen are both white.

Size: Adults have a carapace length of 17.0 - 26.1 mm.

Habitat: Orconectes saxatilis has been collected under rocks in pool areas with little current (Bouchard and Bouchard, 1976).

General Range: Orconectes saxatilis has been taken only from Pigeon Creek, a Kiamichi River system tributary, at the type locality in LeFlore County, Oklahoma (Bouchard and Bouchard, 1976).

Comments: This crayfish is known only from one collection made by Dr. Raymond Bouchard on 11 August 1974 from Pigeon Creek at State Highway 63 in LeFlore County, Oklahoma. Three trips to the type locality during this survey proved futile with regard to collecting this species. With these facts in mind, Orconectes saxatilis is the most rare crayfish on the entire ONF and deserves immediate protection in future management decisions.