Rhithrops capensis Bilton & Shepard 2022, sp. nov.
Creators: name: Bilton, David T.
name: Shepard, William D.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Dryopidae
Rhithrops
Rhithrops capensis

description: Rhithrops capensis sp. nov.
(Figs 1–9)
Type locality. South Africa, Western Cape, Cederberg, Matjies Rivier, Matjiesrivier, 32°31’07.42”S 19°21’00.4”E, 725 m. (Fig. 9).
Type material. Holotype (male): “ 22/ix/2011 South Africa WC// Cederberg, Matjies Rivier // Matjiesrivier 32°31’07.42”S // 19°21’00.4”E, 725 m. D T Bilton leg.” (AMG).
Paratypes (23): 5♂, 10♀ same data as holotype; 1♀ “ 21/ix/2010 South Africa WC// Cederberg, Matjies Rivier // Matjiesrivier 32°31’07.42”S // 19°21’00.4”E, 725 m. D T Bilton leg.”; 2♂, 3♀ “ 22/ix/2011 South Africa WC// Cederberg, Matjies Rivier // Matjiesrivier 32°31’07.42”S // 19°21’00.4”E, 725 m. D T Bilton leg.”; 1♂, 1♀ “ South Africa: W. Cape // Cederberg, Maalgat // Matjiesrivier // 28-29 XII 2004 820 m asl // 32°29’40”S 19°16’49”E // P. S. Cranston, leg.” (AMG, CBP, DMSA, EMEC, NMW).
Description: With all the above characters of the genus.
Size: Holotype: BL 4.10 mm; EL 2.65 mm; EW 1.35 mm; PL 0.85 mm; PW 1.20 mm. Paratypes: Males BL 4.40–4.75 mm; EL 2.60–3.00 mm; EW 1.45–1.60 mm; PL 0.85–1.05 mm; PW 1.20–1.35 mm. Females BL 4.65– 4.80 mm; EL 2.75–2.90 mm; EW 1.40–1.60 mm; PL 0.90–1.05 mm; PW 1.25–1.35 mm.
Head: Epicranium densely and shallowly punctate, with short decumbent setae, epicranial suture absent; frontal area twice as wide as one compound eye, antennal ridges absent, frontoclypeal suture straight between antennal bases.
Elytra: Conjointly twice as long as wide, parallel-sided, apices moderately protruding (Figs 1 & 6D–E).
Legs: Relatively long, elongate, with large, strongly-developed tarsi and claws (Fig. 8A–C).
Male: Last abdominal ventrite with broad, shallow apicomedial emargination (Fig. 7E). Labium with modified, spathulate setae on anteroventral margin (Fig. 4F). Anterior edge of sternite 8 with short median strut (Fig. 9F); sternite 9 as in Fig. 9C. Tergite 8 with numerous long setae close to posterior margin (Fig. 9E).
Aedeagus: Long and tubular (Figs 8D–F & 9A, B & D); basal piece:paramere ratio 0.6:0.4. Basal piece hookshaped basally, open on left side. Median lobe long, narrow, acute apically. Parameres parallel-sided, apically a little longer than median lobe, apices rounded on outer side, clasping apex of median lobe (Fig. 8F).
Female: Few external differences to males. The sublateral furrows of the pronotum are deeper and more evident (Fig. 2B). The last abdominal ventrite has a conical apex, somewhat raised centrally and lacks an apicomedian emargination (Fig. 7F). The labium has fewer, shorter modified setae on the anteroventral margin (Fig. 4E). Sternite 8 as in Fig. 10C.
Ovipositor: Elongate (Fig. 10A–B) and strongly sclerotized; type 1 (sensu Kodada et al. 2016); apically sharp-tipped. Valvifers ventral, asymmetrical, long, thin, forming a V-shaped sclerite. Coxites asymmetrical, laterally compressed, blade-shaped, apex very acute, dorsal side serrate, with basally directed long narrow dorsal extension.
Distribution and habitat. Known only from type locality, the Matjies River (Fig. 11), a tributary of the Olifants River in the Cederberg, Western Cape Province, South Africa.
Etymology. The trivial name, capensis, refers to location of this species in the Western Cape Province of South Africa.
description: Published as part of Bilton, David T. & Shepard, William D., 2022, Rhithrops capensis gen. et sp. nov., a new aquatic dryopid beetle from the Western Cape of South Africa (Coleoptera: Dryopoidea: Dryopidae), pp. 539-553 in Zootaxa 5195 (6) on pages 541-546, DOI: 10.11646/zootaxa.5195.6.3, http://zenodo.org/record/7223884