(Lundbeck, 1898)
Body
Small larvae up to 5 mm long. The body is purple, blue or brownish. On the prothorax the setae are conspicuous and 1/4 of the segment length. On mesothorax, postthorax and abdomen these setae are reduced. The anterior parapods are separate. The two posterior parapods bear rows of claws. Procercus and two pairs of anal tubules present (Wiederholm, 1983; Moller Pillot, 1984b).
Head
In freshly preserved larvae the head is light brown to brown and 0,32 - 0,35 mm long (Schmid, 1993).
Antenna
The antenna consists of 4 segments Euk claripennis antenna. The blade reaches the apex of segment 3. Lauterborn organs are present.
Mentum
The mentum has two median tooth, which is appr. as wide as the first lateral, and 5 pairs of lateral teeth Euk claripennis mentum. The ventromental plates are weak. The beard is absent.
Labrum
The pecten epipharyngis consists of three scales. SI is simpel (Wiederholm, 1983; Moller Pillot, 1984b).
Mandible
The mandible has an apical tooth and 4 inner teeth. The seta interna has simpel, serrate of plumose branche. The mola is serrated (Wiederholm, 1983).
Differential characteristics
E. claripennis can be separated from the other Eukiefferiella species by the double mid-mental teeth being appr. as wide as the first laterals.