Brachystoma

Meigen, 1822

Species Guides

2

Brachystoma is a of small predatory flies established by Meigen in 1822. The genus comprises approximately 30 described distributed across Europe and parts of Asia. Brachystoma was historically placed in Empididae but is now recognized as the type genus of the Brachystomatidae. European species have been subject to recent taxonomic revision.

Brachystoma robertsonii by (c) skitterbug, some rights reserved (CC BY), uploaded by skitterbug. Used under a CC-BY license.Brachystoma robertsonii by Skittlebug. Used under a CC BY 2.0 license.Sigmoria disjuncta-mouth by Skittlebug. Used under a CC BY 2.0 license.

Pronunciation

How to pronounce Brachystoma: /ˌbrækɪˈstoʊmə/

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

Identification

Members of Brachystoma can be distinguished from Empididae sensu stricto by wing venation and genitalic characters. The is characterized by reduced wing venation with a simple anal and distinctive male terminalia. -level identification requires examination of male genitalia and chaetotaxy; several species exhibit distinctive abdominal patterning including maculation and coloration of the scutellum and .

Images

Habitat

occur in diverse terrestrial including grasslands, forest edges, and riparian zones. Specific microhabitat associations vary by species.

Distribution

Europe (Austria, Croatia, France, Germany, Italy, North Macedonia, Poland, Romania, Slovakia, Switzerland) with extension into parts of Asia. The shows a predominantly Palaearctic distribution.

Seasonality

activity period varies by and latitude; most European species are active during spring and summer months.

Life Cycle

Development is holometabolous with , larval, pupal, and stages. Larval is poorly documented but larvae are presumed to be predatory or scavenging in soil or decaying organic matter.

Behavior

are predatory, capturing small prey. A 2025 review discusses possible oviposition , though specific details require examination of the full primary source.

Ecological Role

function as of small arthropods in terrestrial . Larval remains insufficiently documented to assess contribution to soil .

Human Relevance

No documented economic or medical importance. The is of interest to dipterists and systematists due to its taxonomic history and recent -level reclassification.

Similar Taxa

  • Empididae (sensu stricto)Historically confused with Brachystoma; distinguished by wing venation (complete anal in Empididae) and genitalic structure
  • TachydromiinaeSimilar small predatory flies; Brachystoma distinguished by body proportions and wing venation

More Details

Taxonomic History

Brachystoma was long treated as a within Empididae but is now placed in the separate Brachystomatidae ( Brachystomatinae, tribe Brachystomatini) based on phylogenetic and morphological evidence.

Species Diversity

The contains approximately 30 described , with European fauna revised in 2025. Several species were described by Smith in 1969, indicating a mid-20th century period of taxonomic activity.

Sources and further reading