Numbers
one of 15 species in this genus in North America listed at
nearctica.com
very common within its range
Size
body length 6.8-8.6 mm; female larger than male
Identification
body grayish-brown; pronotum with pale middorsal line and conspicuous whitish stripe along lateral margins; second antennal segment slightly longer than third, and segments 2 & 3 (combined) slightly longer than segment 1; adults usually long-winged, occasionally short-winged or wingless; in winged individuals, posterior portion of forewing often shaded with blue
see photo of four adults on page 138 of Stephen Marshall's book
(1)Range
coast to coast in southern Canada and northern United States
Habitat
a habitat generalist: lakes, ponds, temporary or permanent pools, rainwater puddles, sphagnum bogs, wooded swamps, backwaters, rivers and streams
Season
active April to November; overwinters as an adult
Food
living or dead insects on the water's surface
Life Cycle
one generation per year; sometimes a partial second generation
See Also
In Gerris argenticollis, the combined length of antennal segments 2 & 3 equals the length of segment 1, and based on the meaning of the specific epithet, individuals presumably have a silver neck (no photos were found on the Internet); G. argenticollis occurs in the east, has a more southerly distribution, and is found in woodland pools or slow-moving rivers flowing through densely-wooded areas
Internet References
live adult image (Nevada Dept. of Agriculture)
pinned adult images (Insects of Cedar Creek, U. of Minnesota)
presence in Illinois; list (Steve Taylor, U. of Illinois at Urbana-Champaign)
presence in Washington state plus habitats (John Lattin, US National Park Service)
habitat (J.R. Spence, U. of British Columbia, courtesy jstor.org)
sexual dimorphism (Michelle Tseng and Locke Rowe, Canadian Journal of Zoology)
mating behavior in Ontario; PDF doc (Amaya Ortigosa and Locke Rowe, U. of Toronto)
distribution and status; PDF doc (C.J. Drak and Halbert M. Harris, courtesy Ohio State U.)
behavior and biology; PDF doc (Lock Rowe, U. of British Columbia, courtesy U. of Toronto)
parasitism by larval mite Limnochares aquatica; PDF doc (Bruce Smith, U. of New Brunswick, courtesy Ithaca College, New York)
G. argenticollis habitat and distribution; PDF doc (Roland Hussey,
Psyche, Cambridge Entomological Club)
