1. GENUS PROCHYDORUS SMIRNOV, 1992

Smirnov, 1992 a: 112.

Type (sole) species: Prochydorus rotundus Smirnov, 1992 .

Diagnosis: Body very high (in life, animal was probably globular in shape), with postero-dorsal angle well expressed, head massive, with head capsule of the ‘daphniid’ type (not compressed dorso-ventrally), valves without marginal setae, antenna II relatively short, mandible attached to valve margin.