(Edwards, 1929)
Body
Medium sized larvae up to 5.5 mm long. The body setae are < 1/2 the segment. 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 brown (light brown) and 0,39 - 0,43 mm long (Moller Pillot, 1984a; Schmid, 1993).
Antenna
The antenna consists of 5 segments. The blade reaches the apex of segment 4. Lauterborn organs are present (Schmid, 1993).
Mentum
The mentum has one median tooth, which is appr. 3 x as wide as the first lateral, and only 4 pairs of lateral teeth Euk gr ilkeyensis mentum. The ventromental plates are weak. The beard is absent.
Labrum
The pecten epipharyngis consists of three scales. SI is simpel (Wiederholm, 1983; Schmid, 1993).
Mandible
The mandible has an apical tooth and 3 inner teeth. The seta interna has simpel, serrate of plumose branches. The mola is strongly serrated (Schmid, 1993).
Differential characteristics
E. ilkleyensis can be separated from the other Eukiefferiella species by the mentum with only 4 pairs of lateral teeth.