Gerris thoracicus

Gerris thoracicus

Description

10-12mm. Similar to the Common Pondskater, Gerris lacustris, but usually with an orange disc in the centre of the thorax. Two other Gerris species have this but Gerris thoracicus is the commonest of these. It is usually fully winged and able to fly. The antennal segments are all dirty yellow and the yellow stripe of the side of the thorax widens towards the rear.

Similar Species

The other two species with an orange thoracic disc are G. costai (which is larger) and G. lateralis which has patches of silver hairs along each side of the ventral surface of the abdomen.

Identification difficulty
Recording advice

Similar to other members of this family and detailed examination is needed to identify it to species level.

Habitat

Found in ponds and lakes, often those with organically enriched or slightly polluted waters.

When to see it

Eggs are laid in April and May, which give rise to a first generation of adults by mid-summer. These produce a second generation, the adults of which overwinter. 

Life History

Eggs are laid on the floating leaves of aquatic plants.

UK Status

Widespread and fairly frequent in Britain.

VC55 Status

Uncommon or under-recorded in Leicestershire and Rutland.

Leicestershire & Rutland Map

MAP KEY:

Yellow squares = NBN records (all known data)
Coloured circles = NatureSpot records: 2025+ | 2020-2024 | pre-2020

UK Map

Additional images

No additional images available for this species.

All NatureSpot records