Kieffer, 1919
Body
Medium sized larvae up to 6 mm long. The anterior parapods are separate. The two posterior parapods bear rows of claws. Procercus is present. Two pairs of anal tubules present. On the abdominal segments 1 - 7 the L4 bundle consists of appr. 10 setae that are as long as the segment. The L2 is single and only a little shorter than L4 (Hirvenoja, 1973 ).
Head
The head is brown and laterally compressed (Moller Pillot, 1984b).
Antenna
The antenna is reduced and consists of five segments Cric brevipalpis antenna. Mentum
The mentum is laterally compressed and has one median tooth and only 5 pairs of lateral teeth. Median tooth < 2x the first lateral tooth Cric brevipalpis mentum
Labrum
SI is simpel. The premandible with 1 apical tooth (Hirvenoja, 1973).
Mandible
The mandible with a smooth inner side. The apical tooth is shorter than the joined inner teeth.
Differential characteristics
The setal tufts of L4 Cric (C) 14 Cric (I) sylv body seta on the abdominal segments are distinctive for Cricotopus (and Orthocladius holsatus). C. tremulus and C. lygropus have no setal tufts however.
C. brevipalpis can be separated from all other Isocladius by:
the L4 bundle on Segment 1 - 7 consisting of app. 10 setae as long as the segment.
L2 subequal to the segment and reduced antenna and shape of head and mentum.