Common pond skater  (Gerris lacustris)

Common and widespread (3).

The common pond skater is the most widespread British bug. It is brownish-black in colour, with a narrow body. The forelegs are short and used for grasping and holding prey. The middle and hind legs are long and slender; the hind pair are used as 'rudders', while the middle pair of legs are used to propel the bug along the surface of the water (3) with either a rowing or a jumping motion (4). All true bugs have sucking mouthparts, known as a rostrum or 'beak' (3); this pond skater has a short, powerful rostrum (2). Both winged and wingless forms occur; in winged pond skaters the wings are held folded flat against the body (3).

Found throughout the British Isles, with the exception of the Outer Hebrides and the Shetland Isles (3).

Inhabits a wide range of water bodies, including garden ponds, ditches, streams and rivers (3).

Adults emerge after over wintering towards the end of April or in early May, and females lay eggs in May. The eggs take around 12-14 days to develop, but the time taken until hatching is dependent on the temperature. Bugs undergo a type of development known as incomplete metamorphosis in which the larvae or 'nymphs' progress through a series of moults. The stages between moults are known as 'instars'; in this species there are 5 instars, each one progressively longer than the last. It takes between 24 and 30 days for pond skater larvae to develop into adults, with winged forms taking longer to reach maturity (3).

Not threatened at present.

No conservation action has been targeted at this species.

For more on invertebrates and their conservation see Buglife, the Invertebrate Conservation Trust at:
http://www.buglife.org.uk/

• Incomplete metamorphosis: type of insect development (also known as hemimetabolous development) in which the adult form is reached via a series of moults. The larva (nymph) resembles a miniature wingless adult; the wings develop externally as the nymph grows.
• Larvae: stage in an animal's lifecycle after it hatches from the egg. Larvae are typically very different in appearance to adults; they are able to feed and move around but usually are unable to reproduce.

1. National Biodiversity Network Species Dictionary (Jan 2003): http://www.nhm.ac.uk/nbn/
2. Olsen, L., Sunesen, J. & Pedersen, B. V. (1999) Small freshwater creatures. Oxford University Press, Oxford.
3. Southwood, T. R. E. & Leston, D. (1959) Land and water bugs of the British Isles. Frederick Warne & Co. Ltd., London.
4. Macan, T. T. (1959) A guide to freshwater invertebrate animals. Longmans, Green & Co. Ltd., London.