P. dissimilis (Johannsen, 1905) and P. inopertus (Walker, 1856)
Body
Medium sized larvae up to 7 mm long. The posterior parapods bear about 15 simpel claws. The L2 on the abdominal segments is simpel Par dissimilis body setation. (Klink, 1983b; Wiederholm, 1983).
Head
The head is pale to brownish-yellow and S3 is simpel.
Antenna
The antenna stands on a small smooth pedestal and consists of 5 segments. The basal segment is longer than the flagellum. Segment 2 is cylindrical, slightly wedging out at the apex, shorter to much longer than the remaining segments. The lauterborn organs their pedicels and with or without a small distal part. The blade reaches to the middle of the 4th - 5th segment Par dissimilis antenna 8.
Mentum
The mentum has a simpel to slightly notched median tooth and 5 pairs of lateral teeth. The ventromental plates are close together medially and slightly wider than the mentum.
Labrum
SI is a comb and labral lamellae a single plate with 16 - 26 teeth. The pecten epipharyngis consists of a single smooth plate with 5 rounded teeth distally Par dissimilis pect epiph. The premandible has 2 teeth.
Mandible
The mandible with a dorsal tooth, apical tooth and 3 inner teeth. The pecten mandibularis is present and seta interna with branches.
Differential characteristics
The pecten epipharyngis with a single plate with 5 teeth Par austriacus pect epiph is distinctive, although Lithotanytarsus may have a similar pecten epipharyngis. Paratanytarsus lacks the small pairs of median projections on the antennal pedestal however Lithotan emarg antenna.
Paratanytarsus dissimilis agg. can be separated from the other Paratanytarsus by the pecten epipharyngis with 5 teeth and lauterborn organs their pedicels.