Kieffer, 1921
Body
Small larvae up to 5 mm long. The posterior parapods are reduced with simpel claws. The procercus is exceptionally well developed (Wiederholm, 1983).
Head
The S3 is simpel and the dorsal head capsule with numerous warts.
Antenna
The antenna stands on a long pedestal with a large apical projection and consists of 5 segments. The basal segment is subequal to the flagellum. Segment 2 is somewhat wedge-shaped and shorter than the third segment. The Lauterborn organs distally on segment 2 are sessile Thienemanniola antenna.
Mentum
The mentum with a concave row of teeth, has a trifid median tooth with a rounded inner tooth and a pair of very narrow outer teeth and 5 pairs of lateral teeth. The ventromental plates are widely separated and less wide than the mentum Thienemanniola mentum.
Labrum
SI is plumose and not a comb and labral lamellae a single plate with numerous apical teeth. The pecten epipharyngis not discernable and consists of 3 smooth plates with distal teeth. The premandible with 2 sharp apical teeth and 1 blunt inner tooth.
Mandible
The mandible with a dorsal tooth, apical tooth and 2 inner teeth. The pecten mandibularis is present and seta interna with branches.
Differential characteristics
The large posterior projection on the antennal pedestal and the sessile Lauterborn organs are distinctive Thienemanniola antenna. Also the exceptionally strong procercus, reduced posterior parapods, concave mentum, reduced pecten epipharyngis and SI plumose instead of a comb are only present in Thienemanniola.