Phasiinae

bug-killing flies

Phasiinae is a of (: ) comprising that primarily attack (). Members are commonly known as "-killing flies" and include important agents of agricultural pests. The subfamily contains multiple tribes including Phasiini, Gymnosomatini, Trichopodini, Strongygastrini, and Parerigonini. Most species possess specialized for life, including piercing structures for direct insertion into tissues.

Strongygaster triangulifera by (c) Cole Shoemaker, some rights reserved (CC BY), uploaded by Cole Shoemaker. Used under a CC-BY license.

Catharosia by (c) Michael Knapp, some rights reserved (CC BY), uploaded by Michael Knapp. Used under a CC-BY license.

Pronunciation

How to pronounce Phasiinae: //fæˈsaɪ.ɪniː//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Phasiinae can be distinguished from other by the elongated medial plate of the hypandrium in males, a potential morphological . Some exhibit bright coloration and feather-like on the hind (e.g., Trichopoda). The subfamily historically caused taxonomic confusion due to conflicting character states and convergent with other tachinid groups. Molecular now supports the placement of Strongygastrini and Parerigonini within Phasiinae, while Eutherini and Epigrimyiini have been excluded.

Images

Distribution

Worldwide distribution with representatives in the Neotropical, Nearctic, Palearctic, Afrotropical, Oriental, and Australasian regions. The Trichopoda is natively distributed in the Americas. Specific geographic ranges vary by tribe and genus.

Host Associations

Heteroptera - primary ; primary target for most Phasiinae except Strongygastrini
Corecoris batatas - ; documented for Trichopoda
Anasa tristis - ; documented for Trichopoda
Nezara viridula - (); documented for Trichopoda
Brochymena spp. - ; documented for Trichopoda
Largus californicus - ; documented for Trichopoda

Behavior

females use piercing structures to insert directly into tissues; these structures have evolved independently in multiple lineages and have been lost or reduced in others. Some have been observed using host for host-finding.

Ecological Role

agents of agricultural pest , particularly . of in natural and agricultural .

Human Relevance

Important for programs targeting agricultural pests such as () and (). of Trichopoda and related are utilized or studied for pest management. Taxonomic instability has historically hindered research into their practical application.

Similar Taxa

DexiinaeHistorically confused with Phasiinae; Litophasia Girschner transferred from Phasiinae to Dexiinae based on molecular
Strongygastrini (historically)Formerly placed elsewhere; now confirmed within Phasiinae by molecular data, though members do not attack unlike other Phasiinae

More Details

Taxonomic instability

Phasiinae has been unstable for over a century due to homoplastic morphological characters. Recent molecular phylogenetic analysis (2017) provided first including 128 worldwide and 80 , resolving placements of Eutherini, Epigrimyiini, Strongygastrini, and Parerigonini.

Tribal reclassification

Molecular analysis led to redistribution of Phasiini members: Cistogaster, Clytiomya, Ectophasia, Eliozeta, and Euclytia transferred to Gymnosomatini; Opesia to Strongygastrini; Xysta to Xystini. Parerigonini members distributed across Parerigonini, Cylindromyiini, and new tribe Zitini.

Piercing structure evolution

Ancestral state reconstruction indicates that piercing structures for insertion into evolved separately in multiple Phasiinae lineages, with subsequent loss or reduction in several groups.