Andronov, 1973
Females
Ce and Pd1, as well as Pd4 and 5 separate. R with 2 long filaments. Ur of 3 somites with articulated CR. A1 very long, 23-segmented, segments 1-2, 8-9 fused; carrying elongate setae on segments 7, 14, 16, 18, 21, 23 and 24. A2 Exp 8-segmented, shorter than Enp; Exp1 and Exp2 with 2 setae each, terminal segment short. Mx1 Li1 with 12 terminal setae including 4 posterior setae; Li2 and Li3 with 3 setae each; Li4 with 4 setae; Enp with 14 setae; Exp with 11 setae; Le2 small, lacking setae; Le1 with 9 setae. Mx2 Li1-Li5 with 5, 3, 3, 3 and 4 setae respectively. Mxp Coxa with groups of 2, 3 and 4 setae from proximal to distal; Basis with proximal row of long teeth; Enp1-5 with 4, 4, 3, 4 and 4 setae respectively. P1 Enp 1-segmented with an outer lobe.
Spine and seta formula: Spine and seta Mecynoceridae.
P5 uniramous, 5-segmented, symmetrical; no outer edge spines on each Exp segment but 1 inner edge seta on Exp2 and 1 terminal spine and 4 inner edge setae on Exp3.
Males
Pr as in female. Dorsal cephalic hump present. Ur of 5 somites, with articulated CR. A1 25-segmented (21 free segments) with segments 1-2, and 3-6 fused. P1-P4 similar to female, but P1-P4 Coxa with inner seta each. P5 uniramous, 5-segmented, asymmetrical, longer on right.
Monotypic family containing Mecynocera clausi Thompson, 1888.