Couplet 75

75a:  Antenna with 9 antennomeres, last 5 involved in club; abdomen with 6-7 ventrites; tiny intercoxal sclerite present present between hind coxae; maxillary palp long relative to antenna; ventral surface with water-repellent pubescence; < 3.0 mm length

Hydraenidae   p. 408

75b:  Without preceding combination of characters