Helenus White, 1879

Heiss, Ernst, 2016, Review of the Neotropical genus Helenus White, 1879, with description of a new species (Hemiptera: Heteroptera: Aradidae), Zootaxa 4088 (4), pp. 555-562 : 556

Genus Helenus White, 1879

Type species: Helenus hesiformis White, 1879: 85

General appearance, habitus and size of Helenus is very close to that of the Neotropical genus Hesus Stål, 1862 , both distributed in South- and Central America. Usinger & Matsuda, 1959 published detailed redescriptions of both genera ( Hesus p. 368; Helenus p. 369) which need not to be repeated here.

The distinguishing characters are given in their key for the “American Genera of Mezirinae ” p. 203 as follows:

• Body covered with shaggy, erect pubescence. Pronotum without anterolateral lobes. Head without rounded postocular lobes = Helenus White

• Body not pubescent. Pronotum with brief anterolateral lobes bent inward to anterior collar. Head with rounded postocular lobes. = Hesus Stål

The most recent summaries of published records of these genera are given by Heiss, 2009 (Review of Hesus ) and Coscaron & Contreras, 2012 (Catalog of the Aradidae for the Neotropical Region).

Key to species of Helenus

1 (4) Body surface covered with dense shaggy pubescence consisting of shorter yellowish adpressed hairs intermixed with longer erect setae; pe-angles of lateral margins of deltg II–VI not or inconspicuously protruding (Figs.1,6,7).................. 2

2 (3) Pilosity generally more dense, exposed part of male pygophore wide and conical posteriorly, its median dorsal elevation anteriorly depressed along longitudinal suture, raised laterally ( Fig.8 ), parameres more slender ( Fig.11 )....... hesiformis White

3 (2) Pilosity generally less dense, exposed part of male pygophore wide and truncate posteriorly, its median dorsal elevation keellike ( Fig.10 ), parameres with wider body ( Fig.13 )................................................. wachteli n. sp.

4 (1) Body surface granulate, yellowish adpressed hairs intermixed with erect setae less dense and more dispersed; pe-angles of lateral margins of deltg II–VI distinctly protruding ( Fig.2 ); (exposed part of male pygophore triangular narrowly conical posteriorly, median dorsal elevation keel-like ( Fig.9 ), parameres slender ( Fig.12 ))......................... hirsutus Champion

Note: Because of variable colouration, size and density of pilosity, females of hesiformis and wachteli n. sp. can not presently be separated with certainty. The male genitalic structures are distinctive for the three species.

Figures

FIGURES 6 – 10. Helenus spp.: 6 — Helenus wachteli n. sp., holotype male, dorsal view; 7 — Helenus wachteli n. sp., paratype female, dorsal view; 8 – 10. Male pygophore: 8 — hesiformis; 9 — hirsutus; 10 — wachteli n. sp.

FIGURES 11 — 13. Left paramere of Hesus spp.: 11 — hesiformis; 12 — hirsutus; 13 — wachteli n. sp.

FIGURES 1 – 5. Helenus spp.: 1 — Helenus hesiformis, holotype male, dorsal view; 2 — Helenus hirsutus, lectotype male, dorsal view; 3 — labels attached to holotype of hesiformis; 4 — ditto, reverse side; 5 — labels attached to holotype of hirsutus.