Bibio marci or St. Mark's fly or Hawthorn Fly[1] is a species of fly from the family Bibionidae. It is found across much of Europe.[2] Their common name comes from the fact that the adults usually emerge around St Mark's Day, 25 April.

Bibio marci
Bibio marci02.jpg
Male B. marci
Scientific classification edit
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Diptera
Family: Bibionidae
Genus: Bibio
B. marci
Binomial name
Bibio marci


Like most bibionid larvae, they grow up in grassy areas and are herbivores and scavengers feeding on dead vegetation or living plant roots. Bibio marci larvae are known to be root damage pests of celery, asparagus, roses, saxifrages, lawn grass, lettuce and Polyanthus. They also feed on a very large number of plant species that are commercially unimportant.[3]


  1. ^ "Hawthorne Fly". California Academy Of Sciences. Retrieved 21 February 2018.
  2. ^
  3. ^ Freeman, Paul; Lane, Richard P. (1985). "Bibionid and Scatopsid flies, Diptera: Bibionidae & Scatopsidae". Handbooks for the identification of British insects. 9 (7). London: Royal Entomological Society of London: 74. Cite journal requires |journal= (help)

External linksEdit