---
title: "Hawthorn Fly"
description: "Bibio marci — Insects & spiders. Bibio marci or St."
canonical: https://animalchecklist.com/animal/hawthorn-fly
last_updated: 2026-09-20
---

# Hawthorn Fly

> Bibio marci — Insects & spiders. Bibio marci or St.

- Scientific name: *Bibio marci*
- Category: `insects` (Insects & spiders)
- Habitats: unknown
- iNaturalist observations: 16966
- Wikidata: [Q1304179](https://www.wikidata.org/wiki/Q1304179)
- iNaturalist taxon: [56096](https://www.inaturalist.org/taxa/56096)

## Names

- en: Hawthorn Fly
- de: Märzfliege
- fr: Bibion de la Saint-Marc
- nl: Rouwvlieg
- pl: Leń marcowy

## Countries with the most observations

DE (1286), GB (1279), FR (332), RU (182), CZ (151), UA (142), IT (134), AT (133), BE (100), FI (71), PL (69), NL (68)

## Summary

Bibio marci or St. Mark's fly or hawthorn fly, is a species of fly from the family Bibionidae. It is found across much of Europe. Their common name comes from the fact that the adults usually emerge around St Mark's Day, 25 April.

Text: Wikipedia (en), CC BY-SA 4.0 — https://en.wikipedia.org/wiki/Bibio_marci

## Photo

![Hawthorn Fly](https://animalchecklist.com/img/animals/hawthorn-fly/medium.jpg)

Photo: Andreas Manz · CC0 · inaturalist — https://www.inaturalist.org/observations/113620081

## Machine access

`GET https://animalchecklist.com/api/v1/animals/hawthorn-fly?lang=en` — see [openapi.json](https://animalchecklist.com/openapi.json).