Numbers
the largest water bug family, with ~125 spp. in 16 genera in our area
(1) and >600 spp. in 35 genera worldwide
(2) arranged in 6 subfamilies
(3)
selected local faunas: TBA spp. in Canada
(4), ~60 in MI
(5), 30 in FL
(6), 45 in CA & adjacent states
(7), 44 in NH
(8), 23 in OK
(9), ~43 in TX
(10)
Overview of our fauna (* –taxa not yet in the guide):
Family Corixidae
Tribe Corixini Arctocorisa,
Callicorixa,
Cenocorixa,
Centrocorisa,
Corisella,
Hesperocorixa,
Morphocorixa,
Palmocorixa,
Ramphocorixa,
Sigara (subg.
*Allosigara,
Arctosigara,
Lasiosigara,
*Pediosigara,
Phaeosigara,
*Pileosigara,
*Sigara,
*Subsigara,
Vermicorixa,
Xenosigara),
Trichocorixa
Identification
Dorsum flattened, with narrow dark crosslines. Front legs short, tarsi 1-segmented and scoop-shaped. Hind legs oar-like, with fine hairs
(11)
For genus identification please provide:
Dorsal and ventral habitus shots of preferably dry specimen (fluids obscure colour pattern, texture of hemielytra, etc.)
Lateral view. Important are the nodal furrow & area immediately behind it, and translucent (pruinose) areas on claval suture.
Facial shot showing rostrum.
Upper ventral half of the body showing prothoracic lobes, mesepimeron, and scent glands.
Abdominal terga for sexing; males generally have asymmetrical terminalia and may or may not have a black spot-like structure called a "strigil"; females have symmetrical terminalia.
Palae, especially of the male (more critical in species ID)
Size may be important, too.
Keys to genera in
(12)(5)(13)
Species of some genera may be identifiable from photos, but in major genera like Sigara, Hesperocorixa, &c. species IDs are unlikely.
Keys to spp.:
(14) • MI
(5) • FL
(6) • CA
(15)Range
Worldwide and throughout NA
Habitat
Common in ponds. Also found in birdbaths. A few species live in streams, and others are found in brackish pools along the seashore above the high tidemark.
Food
Algae, detritus, other aquatic organisms (mosquito larvae, brine shrimp)
(2); a few (uniquely among Hemiptera) consume small particles of solid food
(1)Life Cycle
eggs cemented to underwater objects, sometimes forming a dense mat
(1)Remarks
Males make sounds by rubbing their front legs against the front of their head
(1).
Micronecta scholtzi is the loudest animal relative to body size.
Unlike
Notonectidae, Corixidae do not bite
Adults fly to lights, sometimes in great numbers
