Aorolaimus torpidus
Thorne and Malek, 1968
Photo Gallery- Nine-mile Prairie

(Thorne and Malek, 1968 description)

L = 0.93 mm; a = 27; b = 7.2 c = ?; V = 56

 Body as open spiral when relaxed, cylindroid exccept at extremities. Lateral fields marked by 4 incisures, slightly crenate on borders. Phasmids usually arranged with one anterior at near 30%, the other posterior at near 80%. In the two specimens examined the positions of the phasmids were reversed, the right being at about 30 and 80, the left at 80 and 30. Cuticle aerolated in region of phasmids, and anteroiorly throughout most of the neck region. Lip region set off by constriction, bearing five annules. Cephalic framework massively sclerotized. Spear 23u long with strong rounded knobs.Spear muscles attached to cephalic framework. Dorsal esophageal glans aperature near spear base. Median bulb spheroid, half width of neck. Basal bulb slightly overlapping intestine dorsally. Hemizonid obscure, anteriorly adjacent to excretory pore. Vulva with small lateral membranes. Epitygma very small, probably single. A thick walled spermagonium present. Intestine not extending into tail. Tail contour more curved dorsally, with 10 annules.

Aorolaimus torpidus is immediately recognized by the conoid, strongly annulated, well set off lip region, spermagonium in uterine tract and dorsally convex tail contour.

Habitat: Hillside thicket 6 miles west of Wilmot, South Dakota.

TOP Notes: This species appears to be a native to the tallgrass prairie. In addition to the type locality, it has been recovered from Kalsow Prairie, Iowa from soil underneath Kentucky bluegrass Poa pratensis (Norton and Schmitt, 1978) and is also found on 9-Mile Prairie, Lincoln, Nebraska underneath leadplant Amorpha canescens. It has not been recovered from any cultivated fields.