Aphelocheirus (Aphelocheirus) malayanus D. Polhemus & J. Polhemus, 1989

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 : 683

Aphelocheirus (Aphelocheirus) malayanus D. Polhemus & J. Polhemus, 1989

( Figs. 53–57 )

Aphelocheirus malayanus D. Polhemus & J. Polhemus, 1989: 216 . Aphelocheirus malayensis: D. Polhemus & Polhemus, 1989: 264 .

Incorrect emendation.

Material examined. — MALAYSIA, Perak: 15 brachypterous males, 20 brachypterous females, waterfall and rocky stream 60 km W. of Jeli , 20 Aug.1985, CL 2081, D. A. & J. T . Polhemus coll. (paratypes, JTPC); 3 brachypterous males, 5 brachypterous females, Iskandar Waterfall, 24 km W. of Tapah on Cameron Highlands road, 450 m, 4°19'28"N, 101°19'30'E, 18 Aug.1985, CL 2074, D. A. & J. T . Polhemus coll. (paratypes, JTPC) . Selangor: 1 brachypterous male, Selangor River nr. Kota Kuba Baharu [Kuala Kuba Bharu], 160 m, 3°34'09"N, 101°41'44"E, 13 Aug.1978, G. F. & C. H. Edmunds coll. (paratype, JTPC) .

Diagnosis. — Brachypterous forms with length 8.9–9.1 mm, maximum width (across abdomen) 5.8–5.9 mm ( Fig. 53 ); macropterous forms with length 8.8–10.1 mm, maximum width (across abdomen) 5.6 mm ( Fig. 54 ). Colouration dark blackish-brown with extensive yellowish markings. This species may be recognised among the local set of Aphelocheirus species occurring in the Peninsular Malaysia by its relatively large size, extensive yellowish colouration on the dorsum, male genitalic structures ( Fig. 55 ), triangular female subgenital plate ( Fig. 57 ), and the absence of raised, dark swellings on the ventral surfaces of the male hind legs.

Distribution. — Described from peninsular Malaysia (Perak), with paratypes from additional Malaysian localities in Perak and Selangor.

Discussion. — Originally described from material collected in Perak, A. malayanus appears to be endemic to Peninsular Malaysia, with records to date from the above state as well as Selangor. No subsequent collections of this species have been reported since the original description. This relatively large, yellowish species is an inhabitant of rocky upland streams, and is somewhat similar in dorsal aspect to A. femoratus , with which it occasionally co-occurs. It is easily separated from the latter species by the absense of raised, dark swellings on the ventral surfaces of the male hind legs ( Fig. 45 ), and other characters as given in the diagnosis.

Figures

Figs.53–57.Aphelocheirus (Aphelocheirus) malayanus D.Polhemus & J. Polhemus, structural details. 53. Brachypterous male, dorsal habitus, specimen from Malaysia, Perak, near Jeli. 54. Macropterous female, dorsal habitus, specimen from Malaysia, Pahang, Cameron Highlands. 55. Male parameres and phallotheca. 56. Proacetabula. 57. Female subgenital plate.

Figs.41–46.Aphelocheirus (Aphelocheirus) femoratus D. Polhemus & J. Polhemus, structural details, specimens from Malaysia, Pahang, Cameron Highlands. 41. Brachypterous male, dorsal habitus. 42. Macropterous male, dorsal habitus. 43. Male parameres and phallotheca. 44. Female subgenital plate. 45. Male hind femur, ventral view. 46. Proacetabula.