Synonyms and other taxonomic changes
our only member of the large, mainly neotropical tribe Sabethini (>500 spp., 14 genera)
(1)Numbers
4 spp. in our area
(2), 140 spp. in 15 genera total
(1)Identification
Adult: wings, legs, proboscis, and palpi dark; palpi very short; hindlegs held high over body and curving forward over head as though mimicking antennae; abdomen dark above, light below, with sharp dividing line along the side
W. vanduzeei has silvery-white scales on antepronotum (anterior edge of pronotum)
W. mitchellii has purplish-black scales on antepronotum
Larva: body cream-colored or whitish; entire length of intestine brown and visible through body surface
W. vanduzeei larva: siphon long, thin, and with few hairs; saddle with long simple hairs and long narrow gills
pupa has circular pigmented areas on second and third abdominal segments
W. mitchellii larva: siphon short with many single hairs; saddle with tuft of short hairs, plus pair of long hairs and shorter wider gills than W. vanduzeei
pupa lacks pigmented areas on second and third abdominal segments
Range
Mostly neotropical
(1); in our area, north to NF-SK
Habitat
W. mitchellii and vanduzeei larvae develop only in water-holding leaf axils (tanks) of bromeliads, which grow as epiphytes on trees.
W. haynei and smithii larvae develop only in tanks of the pitcher plant (Sarracenia purpurea), which grows in acidic sphagnum bogs.
Adults are found near the host plants.
Season
larvae are present most of the year; adults fly from June through fall in the north (extended season in the south)
Food
Larvae of W. mitchellii and vanduzeei filter small particles of organic matter, mostly at the water surface in bromeliad tanks.
Larvae of W. haynei and smithii feed on carcasses of insects and spiders being digested by the enzymes of the pitcher plant.
Adult females of W. mitchellii and vanduzeei bite warm-blooded animals, including humans.
Adult females of W. smithii do not take blood meals; they obtain protein from carcasses of insects and spiders in the tanks of pitcher plants.
Life Cycle
Multiple generations per year. Females deposit eggs on water surface or above waterline on leaves of bromeliads or pitcher plants. Adult lifespan is about 3 weeks. The northern W. smithii overwinters as a larva frozen in a block of ice within a pitcher plant tank.
Remarks
Larvae of W. smithii obtain their oxygen directly from the water, and rarely if ever come to the surface.
