Nychia sappho Kirkaldy, 1901

Nieser, Nico, 2004, Guide To Aquatic Heteroptera Of Singapore And Peninsular Malaysia Iii. Pleidae And Notonectidae, Raffles Bulletin of Zoology 52 (1), pp. 79-96 : 94

Nychia sappho Kirkaldy, 1901

Nychia marshalli var. sappho - Kirkaldy, 1901.

Nychia malayana - Lundblad, 1933; Fernando & Cheng, 1974; Fernando & Leong, 1976.

Nychia sappho - Lansbury 1985 (redescription, synonymy); Kovac & Yang, 1990; Yang et al., 1999.

Diagnosis. – This species is distinguished by the holoptic eyes and the foveate pronotum ( Fig. 11).

Brachypterous form. Length, male 3.6-3.9, female 4.2-4.8; width, male 1.0-1.3, female 1.2-1.4.

Eyes reddish, pronotum and scutellum whitish, middle of scutellum somewhat translucent. Hemielytra largely translucent, whitish back of abdomen shining through. Hemielytra along costal margin with a broad pruinose band variably infuscated, base of hemielytra also pruinose, in females extending caudally to a white to brownish pruinose band running about one third the length of hemielytron about midway between costal and inner margins; some females with two variable brown spots across hemielytral commissure.

Vertex somewhat protruding in front of eyes; eyes holoptic posteriorly. Width of pronotum, male 0.9-1.0, female 1.0- 1.1; pronotum laterally with a pair of foveae. Basal width of scutellum, male & female 0.4-0.7; median length 0.5-0.8. Hemielytra without claval suture, membrane reduced; hind wings absent. Male fore tarsi two-segmented, female fore tarsi one-segmented.

Macropterous form. Length, male 3.9-4.6, female 4.4-4.7; width, male 1.2-1.4, female 1.3-1.4. Colour as in brachypterous form except for hemielytra: clavus largely translucent; corium and membrane pruinose; corium with a narrow longitudinal median translucent stripe, pruinose areas light to medium brown; membrane whitish. Hind wings translucent with a vague whitish hue.

Structurally essentially as brachypterous form except for the scutellum which is much more strongly developed, basal width 0.9-1.2, median length 0.9-1.1. Hemielytra with claval suture present. Membrane and hind wings fully developed.

Distribution. – Widespread, recorded from N Australia and New Guinea through Indonesia, the Philippines and continental SE Asia to Burma ( Lansbury, 1985; Nieser, 1998). Recorded from Johor, Pahang, Perak and Singapore (Fernando & Cheng, 1974; Fernando & Leong, 1976; Kovac & Yang, 1990; Yang et al., 1999). In the ZRC there are also samples from Selangor and Terengganu. The commonest species in the samples of ZRC, which is partly due to the fact that larvae are identifiable to species. Found in virtually stagnant parts of streams and in ponds not connected with streams.