Tobochares luteomargo, Girón & Short, 2021

Giron, Jennifer C. & Short, Andrew Edward Z., 2021, Review of the Neotropical water scavenger beetle genus Tobochares Short & Garcia, 2007 (Coleoptera, Hydrophilidae, Acidocerinae): new lineages, new species, and new records, ZooKeys 1019, pp. 93-140 : 93

Tobochares luteomargo sp. nov. Figs 2D, E , 5A-C , 11D , 13 , 15C, D

Tobochares sp. 10: Short et al. (2021).

Type material examined.

Holotype (male): "Venezuela: Bolivar State/ 7°41'23.6"N, 64°1'56.0"W, 134 m/ ca. 14 km E Rio Aro; 5.viii.2018/ leg. A. Short and M. García / AS-08-073; rock outcropping" (MIZA). Paratypes (282 exs.): Venezuela: Bolívar: " 6°35.671'N, 66°49.238'W; 80 m; Los Pijiguaos; morichal/ rock outcrop; 16.ix.2007; leg. Short, García, Joly; AS-07-015" (17, SEMC including DNA vouchers SLE1028); same, except "seeps and stream at night; 9.vii.2010; leg. Short and Téllez; VZ10-0709-03A" (1, SEMC); Same data as holotype (80, MALUZ, SEMC); " 7°29'47.3"N, 65°51'44.8"W; 45 m; 2 Km E of Río Cuchivero; rock outcrop seeps; 6.viii.2008; leg. Short, Téllez, Arias; AS-08-075" (3, SEMC); " 6°57.904'N, 66°36.392'W; 51 m; outcrop ca. 15 km NE of Los Pijiguaos; detritus flotation; 9.vii.2010; leg. Short and Téllez; VZ10-0709-01B" (2, SEMC including DNA voucher SLE1025); " 7°27.501'N, 65°52.093'W; 45 m; Rock outcrop by Río Cuchivero; seeps; 10.vii.2010; leg. Short, Téllez, Arias; VZ10-0710-01A" (75, SEMC including DNA voucher SLE102); " 7°37.443'N, 64°08.324'W; 90 m; Campamento Río Aro, by Río Aro; rock pools; 11.vii.2010; leg. Short, Téllez, Arias; VZ10-0711-01A" (2, SEMC); same, except "seep scrubbing; VZ10-0711-01B" (48, SEMC); same, except "seep/rock pools at night; VZ10-0711-01E" (44, SEMC including DNA voucher SLE451).

Differential diagnosis.

Tobochares luteomargo can be distinguished by the yellow band along the outer margins of the body (Fig. 5B ).

Description.

Size and form: Body length 1.7-2.1 mm. Body elongate oval, moderately convex (Fig. 5B ). Color and punctation: Dorsal surfaces of body dark brown, with clypeus (Fig. 2A ), outer margins of pronotum, and outer margins of elytra yellowish brown (Fig. 5A, B ); maxillary and labial palps yellow, remainder mouthparts orange; antennae yellowish brown; legs orange brown with paler (yellow) tarsi; ventral surfaces brown (Fig. 5C ). Ground punctation on head, pronotum and elytra moderately marked (Figs 2A , 5A ). Head: Eyes in dorsal view with anterior margin oblique and anteriorly directed (Fig. 2A, B ), and outer margins slightly bulging from outline of head; in lateral view, eyes not anteriorly emarginate (Fig. 2B ). Maxillary palps as long as 0.8 × width of head. Thorax: Elytra with all kinds of punctures similar in size and degree of impression, moderately aligned in rows, not forming grooves (Fig. 5A ). Elevation of mesoventrite forming a very low transverse carina (Fig. 5C ). Metaventrite with distinct median, longitudinal, glabrous area, 3 × longer than wide, extending along posterior half (Fig. 5C ). Abdomen: Abdominal ventrites uniformly and very densely pubescent (Fig. 5C ). Aedeagus (Fig. 11D ). Basal piece 2 × longer than a paramere; greatest width of a paramere nearly 0.6 × greatest width of median lobe; outer margins of parameres slightly sinuate, inner margins strongly sinuate; apex of paramere sharply acute, pointing towards longitudinal midline of aedeagus; median lobe roughly sagittate, medially with narrow emargination extending along apical fourth; gonopore situated nearly at apical third of median lobe.

Etymology.

Named with the Greek words luteo, meaning yellow, and margo meaning margin, in reference to the striking yellow band surrounding the marginal areas of these beetles.

Distribution.

This species is known from several localities along the northwestern edge of the Guiana Shield in Bolívar State, Venezuela. See Fig. 13 .

Life history.

Tobochares luteomargo is found on rock seeps on granitic inselberg-like habitat. Some of these seeps may be very small, less than half a square meter in size. The largest series of this species were collected in seeps on which there was abundant apparent lichen growth, and specimens were often hiding under these growths (Fig. 15E ).

Figures

Figure 2. Heads of Tobochares spp. A, B T. goias, black mark pointing to Tobochares canthus emarginating the eye A dorsal view B anterolateral view C T. fusus D, E T. luteomargo, black mark pointing to straight anterior margin of the eye D dorsal view E anterolateral view F T. romanoae G T. pemon H T. communis I T. microps.

Figure 5. Habitus of Tobochares spp. in the Tobochares luteomargo and Tobochares emarginatus species group A-C T. luteomargo A dorsal view B lateral view C ventral view. D-F T. fusus D dorsal view E lateral view F ventral view. Scale bars: 1 mm.

Figure 11. Aedeagi of Tobochares spp. A T. benettii B T. goias C T. fusus D T. luteomargo E T. pemon F T. anthonyae G T. atures H T. communis I T. microps J T. romanoae K T. akoerio L T. kappel M T. arawak N T. canaima. Scale bars: 0.5 mm (A-D); 0.1 mm (E-N).

Figure 13. Distribution of Tobochares spp.

Figure 15. Tobochares habitat in Guyana and Venezuela A, B habitat for T. arawak, Guyana, upper Potaro River (collecting event GY 14 - 0312 - 01 B) C, D habitat for T. luteomargo, Venezuela, rock outcrop by Rio Cuchivero, (collecting event VZ 10 - 0710 - 01 A) E habitat for T. luteomargo, Venezuela Campamento Rio Aro (collecting event VZ 10 - 0711 - 01 B) F type locality and habitat for T. atures, Venezuela, Tobogan de la Selva (collecting event VZ 09 - 0114 - 01 F).