Isochaetides freyi (Brinkhurst)
Recognition
The dorsal bundles with bifid or simple chaetae but no hairs.
Only mature worms can be identified.
The anterior bundles have up to 8 chaetae, the upper tooth is thin.
The posterior bundles have only 2 or 3 chaetae.
The spermathecal chaetae are long, thin and parallel-sided,
the penial sheath is short and thin.
Summary
Formerly in Peloscolex.
A small tibificid (20 - 25 mm) that is rarely abundant,
but favors mesotrophic conditions.
Distribution
A widespread nearctic species.
13 APR 1996 D.L. Gustafson
AIM home page
dlg@rivers.oscs.montana.edu