Heleocoris, Stal, 1876

Polhemus, Dan A. & Polhemus, John T., 2013, Guide To The Aquatic Heteroptera Of Singapore And Peninsular Malaysia. Xi. Infraorder Nepomorpha- Families Naucoridae And Aphelocheiridae, Raffles Bulletin of Zoology 61 (2), pp. 665-686 : 674

Genus HELEOCORIS Stål, 1876

Discussion. — The type-species of Heleocoris is H. obliquatus Spinola , described from Bombay, and designated by Stål (1876) as the genotype. The genus contains 29 species, of which 14 occur in southern and southeastern Asia, 11 in India, and 3 in Madagascar (J. Polhemus & D. Polhemus, 2008a). The one Neotropical species still held in this genus, Heleocoris plaumanni De Carlo , is assigned here on a provisional basis pending examination of further material, with all other Neotropical taxa formerly placed in Heleocoris having been transferred to Ctenipocoris (J. Polhemus & D. Polhemus, 2008b) . Of the 14 Southeast Asian taxa, four are known from continental Southeast Asia, nine from the Sunda Islands, and one from the Philippines. The generic limits of Heleocoris in relation to the closely related genus Laccocoris are poorly constrained, and certain Asian species currently held in the latter genus may eventually prove to be more properly assigned to Heleocoris .

The apex of the foreleg in Heleocoris bears two tarsal segments in males and only a single segment in females, with two small apical claws present in both sexes. The male phallotheca is asymmetrical, and its shape is useful for species separation ( Figs. 24–28 ). The male proctiger is relatively large, roughly triangular, and lies over the top of the phallotheca in the intact genital capsule; its shape may also be useful for species discrimination ( Figs. 29, 30 ), and care should be taken not to damage it during dissection. The male parameres are highly reduced and often inconspicuous ( Figs. 24–28 ), but their shapes are also interspecifically distinctive. In certain species, male left paratergite VI may also bear a distinctive lateral process ( Figs. 34, 35 ). The female subgenital plate is roughly trapezoidal, and its shape is once again useful for species separation ( Figs. 31, 32 ), although this structure is often thickly covered with long gold hairs which may create difficulty in ascertaining its precise details.

Figures

Figs. 24–28. Heleocoris species, male phallotheca. 24. Heleocoris malayensis, new species, specimen from Malaysia, Terengganu, Sungai Brang. 25. Heleocoris montandoni Lundblad, specimen from Singapore, Nee Soon swamp forest. 26. Heleocoris nebulosus Montandon, specimen from Indonesia, Bali, Melangit River. 27. Heleocoris ovatus Montandon, specimen from Vietnam, Lam Dong Prov., Pongour Falls, CL 3091. 28. Heleocoris strabus Montandon, specimen from Thailand, Chiang Mai Prov., Huay Hia Creek, CL 2198.

Figs. 29, 30. Heleocoris species, male proctigers. 29. Heleocoris montandoni Lundblad, specimen from Singapore, Nee Soon swamp forest. 30. Heleocoris malayensis new species, specimen from Malaysia, Terengganu, Sungai Brang.

Figs. 34, 35. Heleocoris species, male left abdominal paratergites. 34. Heleocoris malayensis, new species, specimen from Malaysia, Terengganu, Sungai Brang. 35. Heleocoris ovatus Montandon, specimen from Vietnam, Lam Dong Prov., Pongour Falls.

Figs. 31, 32. Heleocoris species, female terminal abdomen, ventral view, showing shape of subgenital plate. 31. Heleocoris montandoni Lundblad, specimen from Vietnam, Lam Dong Prov., CL 3094. 32. Heleocoris malayensis, new species, specimen from Malaysia, Perak, Kerunai River, CL 2078.