Prionchulus muscorum
(Dujardin, 1845) Wu and Hoeppli, 1929

Female.  Body curls in cane-like shape when relaxed by heat;  with blunt anterior termini and conoid-arcuate posterior termini.  Labial papillae and lips distinct; lip region set off by depression. Buccal cavity slightly more than twice as long as wide, with medium-sized dorsal tooth in upper fifth of cavity, opposed by single row of eleven denticles arranged along longitudinal rib.  Amphid apertures small, about one sixth as wide as cavity, at level of apex of dorsal tooth.  Esophagus with nerve ring and excretory pore at upper third.  Didelphic; vagina with triangular pieces near entrance.  Arcuate tail elongate-conoid with blunt terminus; without spinneret; usually with three caudal pores, two dorsal (at terminal third and opposite anus) and one submedian (between middle and anterior third).

Habitat.  A common inhabitant of western Oregon soils and about the root area of many kinds of plants.  This species is most abundant in uncultivated soil along the ocean shore line and stream banks, but it also occurs in cultivated soils such as those used for nursery and strawberry production.
Oregon distribution.  Alsea, Aurora, Brookings, Cape Meares, Central Point, Clackamas, Hoskins, Lewisburg, Monroe, Netarts, Pacific City, Valsetz, and along stream banks of many coastal streams.

-Jensen and Mulvey, 1968