Williston-1887
Guides
Microdon ruficrus
spiny-shield ant fly
An uncommon syrphid fly of the eastern United States and adjacent Canada. Adults are metallic greenish or bluish black with distinctive cupreous thoracic stripes and a spiny scutellum. Larvae develop within nests of the ant Lasius americanus. The species is one of approximately 6,200 described syrphid flies worldwide.
Microtabanus pygmaeus
Microtabanus pygmaeus is a species of horse fly in the family Tabanidae, described by Samuel Wendell Williston in 1887. It belongs to the genus Microtabanus, which comprises small-bodied tabanid flies. The species epithet 'pygmaeus' refers to its diminutive size relative to other horse flies. Like other members of the family, adults likely possess the large compound eyes and piercing-sucking mouthparts characteristic of blood-feeding female tabanids, though specific biological details remain poorly documented.