Tepuidessus grulai, Kodada & Hendrich & Balke, 2018

Kodada, Jan, Hendrich, Lars & Balke, Michael, 2018, Tepuidessus grulai sp. nov. from Acopán Tepui in Venezuela (Coleoptera: Dytiscidae: Hydroporinae: Bidessini), Zootaxa 4434 (3), pp. 561-572 : 563-566

publication ID	https://doi.org/ 10.11646/zootaxa.4434.3.10
publication LSID	lsid:zoobank.org:pub:E4DBB0C4-2C3F-4F23-B41A-4C40FEB448B0
DOI	https://doi.org/10.5281/zenodo.5978753
persistent identifier	https://treatment.plazi.org/id/03CBED67-FF92-897A-F9C5-11FC3CE546D0
treatment provided by	Plazi
scientific name	Tepuidessus grulai
status	sp. nov.

Treatment

Tepuidessus grulai View in CoL sp. nov.

Type locality. Acopán Tepui, ca. 2,000 m, 5.194N 62.045W, Venezuela. GoogleMaps

Holotype, male ( ZSM): " Venezuela: Estado Boliver, puddles on rocks in Acopantepui base camp" / " 2022m, 14.xi.2015, 5.19413°[N] -62.04478°[W], ( VEN 6 About VEN /Nov2015)" / " Holotype Tepuidessus grulai sp. nov., Kodada, Hendrich & Balke des. 2018" [red printed label] . Paratypes: 43 exs with the same label data as holotype (CHF, CKB, MIZA, NMPC, ZSM). Each paratype is provided with a red printed paratype label.

Description of holotype. Habitus slightly broad oval, outline with particularly distinct discontinuity between pronotum and elytra ( Figs 3–4 View FIGURE 3 View FIGURE 4 ). Pronotum broadest before its midlength. Elytra widest at about midlength. Total length: 1.8 mm; maximum width: 0.9 mm.

Colouration. Black dorsally, dark brown to black ventrally ( Figs 3 View FIGURE 3 , 4 View FIGURE 4 , 5 View FIGURE 5 ).

Surface sculpture. Head with distinct microreticulation and few setiferous punctures ( Fig. 4A View FIGURE 4 ). Pronotum and elytron shiny ( Fig. 3A View FIGURE 3 ), mostly polished and distinct microreticulation only visible along pronotal margins; whole surface with dense and coarse setiferous punctation, exceptionally coarse and deep on disc ( Fig. 6C View FIGURE 6 ). Ventral surface microreticulate, abdominal ventrites 3–6 shinier; venter with distinct setiferous punctation; posterior margins of ventrites 3–5 without denticles (present in Neotropical genus Bidessodes Régimbart, 1895 ; see Miller & Bergsten 2016).

Structures. Antenna stout, moniliform. Head without occipital line and with rounded clypeus (as in Fig. 4 View FIGURE 4 ). Pronotum without lateral bead; with distinct and very deep basal striae (as in Figs 6A, C View FIGURE 6 ). Elytron with short and deep basal striae, but without sutural line, with distinct longitudinal depression on elytral disc roughly in middle of each elytron (as in Fig. 3B View FIGURE 3 , arrow). Basal epipleural transverse carina absent. Metathoracic wings vestigial, reduced to short membranous vestiges without any sign of venation ( Fig. 6 View FIGURE 6 ). Pro- and mesotarsi appearing stout because tarsomeres 1–3 distinctly dilated laterally; metatrochanter moderately offset.

Male genitalia. Median lobe of aedeagus simply curved, long in lateral view; in ventral view, slender and gently narrowed towards tip ( Figs 7A, B View FIGURE 7 ); lateral lobes (parameres) bisegmented and of a general Bidessini type (see Biström 1988), tip of distal joint rounded ( Fig. 7A View FIGURE 7 ) and with no obvious "nose" or hook (as in e.g. Balke et al. 2015: fig. 31; Biström 1988: fig. 15).

Female. Dorsal and ventral surface dull due to well impressed microreticulation between surface punctation ( Figs 3B View FIGURE 3 , 4B View FIGURE 4 , 5 View FIGURE 5 ). Apical ventrite flattened before posterior margin, tip in lateral view beak-shaped ( Fig. 6B View FIGURE 6 ).

Size variation. Total length: 1.7–1.8 mm; maximum width: 0.7–0.9 mm.

Differential diagnosis. Using the key of Miller & Bergsten (2016: 220), the new species from Acopán Tepui does not key out with Tepuidessus , but with Papuadessus Balke, 2001 , a genus endemic to the Papuan region. The two Papuadessus species are morphologically rather divergent and considered members of one lineage only based on DNA sequence data ( Balke 2001; Balke et al. 2013; Miller & Bergsten 2016). In the absence of any obvious morphological apomorphy that would group the species treated here with Papuadessus , or indeed any other genus, we opt for the pragmatic approach to assign it to Tepuidessus .

Tepuidessus grulai sp. nov. differs from T. breweri by (1) much broader habitus with distinct outline discontinuity between pronotum and elytra, (2) well developed, long and deep basal striae on pronotum and elytra and (3) by unbordered apical abdominal ventrite. The median lobe of aedeagus is more narrowed than in T. breweri in lateral view.

Etymology. Named after Daniel Gruľa, one of the collectors of the new species. It is a noun in the genitive singular.

Distribution. Only known from the type locality ( Fig. 8 View FIGURE 8 ). This locality is situated around 140 km west of Mount Roraima, the locality of the other Bidessini species described from the plateau of a tepui.

Habitat. Puddles on rocks of summit plateau of Acopán Tepui ( Fig. 10 View FIGURE 10 ).