Rhithrops capensis gen. et sp. nov., a new aquatic dryopid beetle from the Western Cape of South Africa (Coleoptera: Dryopoidea: Dryopidae) Author Bilton, David T. 0000-0003-1136-0848 School of Biological and Marine Sciences, University of Plymouth, Drake Circus, Plymouth PL 4 8 AA, UK. d. bilton @ plymouth. ac. uk; https: // orcid. org / 0000 - 0003 - 1136 - 0848 & Department of Zoology, University of Johannesburg, PO Box 524, Auckland Park, Johannesburg 2006, South Africa. d.bilton@plymouth.ac.uk Author Shepard, William D. 0000-0003-4664-2597 Essig Museum of Entomology, 1101 Life Sciences Bldg. # 4780, University of California Berkeley, CA 94720 USA. William. Shepard @ csus. edu; http: // orcid. org / 0000 - 0003 - 4664 - 2597 hepard@csus.edu text Zootaxa 2022 2022-10-17 5195 6 539 553 journal article 168727 10.11646/zootaxa.5195.6.3 893c13e2-2785-463d-b114-a499cbe8a7c8 1175-5326 7223884 EB51F148-8EFC-4B22-9B74-1DBE4EB3A544 Revised key to South African Dryopidae genera The key below is based on that of Nelson (2007) , adapted to incorporate Rhithrops gen. nov. and Pedestrodryops Kodada, 2001 . 1 Almost entire dorsum and venter with long, fine, sparse erect sensillae; terrestrial, in plant litter away from water … Pedestrodryops Kodada, 2001 - Cuticular vestiture shorter and denser; aquatic taxa.......................................................... 2 2 Eyes conspicuously pubescent.......................................................................... 3 - Eyes not conspicuously pubescent, at most with scattered peg-like setae between facets............................. 4 3 First antennomere elongate; second antennomere large, transverse, more or less rectangular, distal border rounded......................................................................................... Ahaggaria Bollow, 1938 - First antennomere not elongate; second antennomere enlarged, ear-shaped, distal border angular...... Dryops Olivier, 1791 4 Antennae with 10 antennomeres; second antennomere enlarged, ear-shaped, covering most of rest of antennomeres; pronotum with sublateral furrows but no carinae..................................................... Rhithrops gen. nov. - Antennae with fewer than 10 antennomeres; second antennomere smaller; pronotum with sublateral stepped carinae...... 5 5 Antennae with 9 antennomeres; sublateral pronotal carinae with lateral flange; prosternal process large, gradually narrowed apically; mesotibial cleaning fringe a dense tuft of golden setae; ovipositor with coxites dorsally serrate Strina Redtenbacher, 1867 - Antennae with 7 antennomeres; lateral margin of pronotum without lateral flange; prosternal process large, abruptly narrowed apically; mesotibial cleaning fringe not a dense tuft of golden setae; ovipositor with coxites not serrate dorsally........................................................................................... Rapnus Grouvelle, 1899