Scientists from Zoological Survey of India (ZSI) have discovered new species of water strider named Ptilomera nagalanda Jehamalar and Chandra in Nagaland. It was found in river Intanki in Peren district of Nagaland.
This newly discovered species belongs to Ptilomera agriodes genus. It measures about 11.79 mm and has long slender legs. It has orange with black stripes on dorsal side and pale yellowish brown ventral part of body. The presence of black stripes on dorsal side differentiates this species from other known species of subgenus Ptilomera. It is only found in rocky, fast flowing streams and rivers that are not exposed to lot of sunlight. It has hair on middle legs that help insects resist strong current of streams.
Water striders aregroup of insects adapted to life on surface of water, using surface tension to their advantage. Their presence serves as indicator water of water quality and also play important role in food chain in river ecosystem as they feed on mosquito larvae.
Water striders have three pairs of legs. The front legs are relatively shorter than mid and hind legs and used to catch and hold prey. They possess needle-like mouth parts that are used for sucking the juice of prey. There are nearly 100 species of water striders found in India across different water bodies such as open ocean, ponds, pools, lakes, rivers, streams etc.
With discovery of Ptilomera nagalanda, the number of species of water striders belonging to subgenus Ptilomera has increased to six in India. These includes Ptilomera agriodes found in peninsular India, Ptilomera laticaudata, northern and northeastern India, Ptilomera assamensis found in northeastern India, Pltilomera occidentalis from Uttarakhand and Ptilomera tigrina found in the Andaman islands.