Chalcosyrphus valgus
VU

Chalcosyrphus valgus

Local name: Sort træsmuldsvirreflue

UnknownLCEULCEU

Photo: Wikimedia Commons (CC) via https://en.wikipedia.org/wiki/Chalcosyrphus_valgus

Overview

A detailed profile for this species is sourced from the IUCN Red List of Threatened Species as assessments become available.

Sort træsmuldsvirreflue faces severe habitat loss due to intensive forestry practices that remove the dead and decaying wood essential for its larval development. Climate change poses additional pressure by altering forest moisture regimes and accelerating decomposition rates of fallen timber. The species' specialized breeding requirements in specific types of rotting wood make it particularly vulnerable to forest management practices that prioritize timber extraction over habitat diversity.

Threat summary

Habitat

This hoverfly species inhabits mature deciduous and mixed forests where it depends on dead and decaying wood for larval development. Adults are typically found in forest clearings and edges where they feed on flowers, while larvae develop in the rotting wood of fallen trees and branches.

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Frequently asked questions

Why is Sort træsmuldsvirreflue classified as Vulnerable?
Sort træsmuldsvirreflue is classified as Vulnerable because the population is declining and the species faces a high risk of extinction in the medium-term future if current pressures continue. Sort træsmuldsvirreflue faces severe habitat loss due to intensive forestry practices that remove the dead and decaying wood essential for its larval development. Climate change poses additional pressure by altering forest moisture regimes and accelerating decomposition rates of fallen timber. The species' specialized breeding requirements in specific types of rotting wood make it particularly vulnerable to forest management practices that prioritize timber extraction over habitat diversity.
Where does Sort træsmuldsvirreflue live?
Sort træsmuldsvirreflue occurs in Åland Islands, Austria, Belarus, Belgium, Canada, and Denmark (plus 16 other countries). Country-level distribution data is sourced from the IUCN Red List and cross-referenced with GBIF occurrences.
What are the main threats to Sort træsmuldsvirreflue?
The main threats to Sort træsmuldsvirreflue are ai-1, ai-2, ai-3, and ai-4. The full IUCN-classified threat record for this species is detailed on the species page.

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