(Goetghebuer, 1921)
Body
Medium sized larvae up to 7.5 mm long. A very shallow hump is present on the 11th segment. The L2 setae on the abdomen are simpel Microps atr L2 pict. The posterior parapods bear about 50 simpel claws Microps gr atrof claws. Supra-anal-setae are sturdy and clearly visible at 40 x magnification (Klink, 1982a; Wiederholm, 1983).
Head
The headcapsule pale and the S3 is branched Mips bidentata setae frontocl.
Antenna
The antenna pale and stands on a pronounced pedestal with a very large apical spur Mips bidentata head dorsal. The distance between the antennal pedestals at most 30 µm. The basal segment 275 - 350 µm long. Segment 2 is cylindrical and longer than the remaining segments. The small Lauterborn organs distally on segment 2 with a very long pedestal.
Mentum
The mentum has a crenate median tooth and 5 pairs of lateral teeth Micropsectra mentum. The ventromental plates are close together medially and wider than the mentum.
Labrum
SI is a comb, SII is serrate with the teeth subequal to the apex and labral lamellae a single plate with 24 - 26 apical teeth. The pecten epipharyngis consists of 3 scales with distal teeth. The premandible with 2 teeth Mips labrum pe premandible.
Mandible
The mandible with a dorsal tooth, one apical tooth and 3 inner teeth all brown. The pecten mandibularis is present and seta interna with branches.
Differential characteristics
Distinctive for most species is the small apical spur on the antennal pedestal Mips small spur ant pedestal. M. bidentata with a large projection Mipsbi large distal proj ant p can be separated from Tanytarsus gr. brundini by the larger number of claws and Micropsectra fusca (with a bare pedestal and a distinct hump on the 11 segment) can be separated from Krenopsectra by its much larger size (10 mm vs 5 mm in Krenopsectra).
M. bidentata can be separated from the other Micropsectra by the very large spur on the antennal pedestal Mips bidentata head dorsal, resembling that of Tanytarsus gr. brundini, which however bears only approx. 15 claws on the posterior parapods (M. bidentata about 50).