Family Tachinidae - Parasitic Flies

current taxonomy in(1)

Tachinidae Robineau-Desvoidy 1830

Second largest dipteran family (after Tipulidae), with ~1350 spp. in >300 genera of 4 subfamilies in our area(1) and >10,000 spp. in ~1600 genera worldwide; it is possible that only half of the species have been described(2)(3)(4)

* –taxa not yet in the guide; classification adapted from the North American catalog(1) updated by the African catalog(5)

Family Tachinidae

SUBFAMILY DEXIINAE

SUBFAMILY EXORISTINAE

SUBFAMILY PHASIINAE

SUBFAMILY TACHININAE

Many tachinids are similar in general appearance to muscids and flesh flies; many are large, bristly, and beelike or wasplike in appearance. Presence of a subscutellum is a useful character:

  

Bristle pattern, facial conformation, and antennal shapes all help identify genera; images that show these features have a better chance of being identified.

Key to e. US genera(6)

worldwide and throughout NA

larval hosts: insects and a few other arthropods (millipedes, spiders, scorpions)(2)(8); adults may take nectar

Current knowledge summarized in(2)

Larval stages are parasitoids of other arthropods; hosts include members of 11 insect orders, centipedes, spiders, and scorpions. Some tachinids are very host-specific, others parasitize a wide variety of hosts. The most common hosts are caterpillars. Some tachinids deposit their eggs directly on the body of their host, and it is not uncommon to see caterpillars with several tachinid eggs on them. Upon hatching the larva usually burrows into its host and feeds internally. Full-grown larva leaves the host and pupates nearby. Some tachinids lay their eggs on foliage; the larvae are flattened and are called planidia; they remain on the foliage until they find a suitable host.

Eggs larvae puparium

Most hibernate in the pupal stage.

Examples of eggs on hosts

At least 16 species have been introduced as biological controls (Grenier 1988)

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