Helobata sp.

Clarkson, Bruno & Almeida, Lúcia M., 2018, On Brazilian Helobata Bergroth, 1888 (Coleoptera: Hydrophilidae) II: new distribution data, Papéis Avulsos de Zoologia 58, pp. 1-6 : 5

Helobata sp.

( Figs. 9-11 )

Material examined: BRAZIL: Goiás State: Jataí Municipality:“Faz.Nova Orlandia/ Jataí, GO – Brasil/ I. 964 – Martins,/ Morgante & Silva// Helobata sp. / Clarkson det. 2018” (1 female: MZSP).

Distribution: Brazil ( Fig. 12 ): Goiás State, Center-West Region.This is the first mention of the genus in Goiás.

Discussion: Identification of Helobata species is usually based mainly on the shape of clypeus and general morphology of male genitalia since the external morphology of the species is similar ( Fernández & Bachmann, 1987). García (2000) and Clarkson et al. (2016) proposed relevant external features for diagnosis and interspecific discernment (see Clarkson et al., 2016).The examined specimen is probably a new species and although we are here providing relevant features to diagnose it, we believe it is wiser to wait with formal description until male specimens are found.On the other hand, we are herein adding this morphotyped specimen in the previously published key to Brazilian species in order to help in the identification of the male when it is found.

The examined species is distinguishable from remaining described species by the combination of the following morphological features: shape narrowly oval (laterally constricted) ( Figs. 9-10 ), moderate-sized species (5.25 mm in length); dorsum brown with black areas; head and pronotum without metallic sheen; pronotum with faintly delimited central dark brown area; with inconspicuous black spots around scutellum and some black spots spread throughout elytral disc ( Fig. 9 ); abdominal ventrites brown ( Fig. 11 ); clypeal disc and frons shagreened on interstices of ground punctuation; fine and very short, decumbent setae distributed on anterior half of the clypeus, and on lateral portions of frons; anterior clypeal margin largely convex ( Figs. 9-10 ); frontoclypeal suture distinct ( Fig. 9 ); maxillary palpomere 3 and 4 subequal in length; mentum finely rugose on lateral portions ( Fig. 10 ); punctures on elytral rows fine, striae weakly marked, irregularly spaced on row 10 ( Fig. 10 ). Posteromedial elevation on mesoventrite semi-trapezoidal, very wide (1.60x longer than wide), medial portion somewhat convex, with raised lateral carinae, oblique and converging anteriorly, widely distant, strongly connected with the metaventral projection ( Fig. 10 ); metaventral projection (between mesocoxae) forming an elevated longitudinal carina, strongly and widely connected posteriorly with metaventral medial carina; metaventral medial carina rising gradually until connecting to metaventral projection ( Fig. 10 ).

Figures

Figure 12. Updated distribution map of the Helobata Bergroth species in Brazil based on Fernández & Bachmann(1987),Clarkson et al.(2016) and the current work.

Figures 7-11. (7-8) Helobata amazonensis Clarkson,Santos & Ferreira-Jr. Habitus, (7) dorsal view, (8) ventral view, scale = 2.0 mm; (9-11) Helobata sp. Habitus, (9) dorsal view,(10) ventral view,scale = 2.0 mm;abdominal ventrites,(11) ventral view,scale = 1.0 mm.