Merycomyia whitneyi
(Johnson, 1904)
Whitney's Horse Fly
Merycomyia whitneyi is a horse fly in the Tabanidae notable for its highly unusual among tabanids. possess non-functional mouthparts and do not feed, representing a dramatic departure from the blood-feeding typical of the family. Larvae develop in aquatic or semi-aquatic , require 2-3 years to mature, and are cannibalistic, necessitating isolation for successful rearing. The is known from Canada and the United States, with detailed biological studies conducted in South Carolina.
Pronunciation
How to pronounce Merycomyia whitneyi: //ˌmɛrɪkoʊˈmaɪə ˈwɪtni.aɪ//
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Identification
can be distinguished from other Tabanidae by their non-functional mouthparts; unlike typical horse flies and deer flies, they cannot bite and lack the used for blood-feeding. Larvae, known colloquially as 'sandworms,' are found in mucky sand and detritus at water margins rather than in typical terrestrial or purely aquatic substrates used by other tabanid larvae.
Habitat
Aquatic and semi-aquatic environments, specifically the edges of cypress-gum ponds where larvae inhabit mucky sand and accumulated detritus. masses are deposited on vegetation overhanging water.
Distribution
Canada and the United States. Specific study documented in South Carolina; broader North American range details limited.
Seasonality
emerge in late May through June. occurs in late spring following 2-3 years of larval development.
Life Cycle
Complete with four stages: , larva, pupa, and . Eggs are laid in masses on overhanging vegetation and coated with a viscous substance. Larval development spans 2-3 years. occurs in late spring, with adult in late May through June.
Behavior
do not feed and possess non-functional mouthparts, making them one of the few non-biting members of Tabanidae. Larvae are cannibalistic and must be isolated to successfully rear to adulthood.
Human Relevance
Larvae, known as 'sandworms,' are used as fish .
Similar Taxa
- Other Tabanidae (horse flies and deer flies)Most Tabanidae are blood-feeders with functional ; M. whitneyi adults are distinguished by their non-feeding habit and reduced mouthparts. Most tabanid larvae develop in terrestrial substrates or flowing water rather than the stagnant pond-edge muck inhabited by M. whitneyi.
More Details
Rearing Challenges
The cannibalistic nature of larvae makes this difficult to rear in captivity, requiring individual isolation for successful development to adulthood.