La piste donnée par Patrick était excellente.
C'est le nom que les anglo-saxon donne aux larves d'un ensemble de familles de diptéres, qui vivent habituellement cachées mais parfois se réunissent pour effectuer une migration à la recherche de nourriture.
Fungus Gnats in the Yard
http://ipm.ncsu.edu/current_ipm/06PestN ... tnews.html
http://en.wikipedia.org/wiki/Fungus_gnatThe maggots stick together and slither along in a ribbon sometimes as much as one inch wide and a yard long so that the mass of larvae resembles a silvery snake!
A MIGRATING ARMY OF SCIARID LARVAE IN THE PHILIPPINESFungus gnats are small, dark, short-lived flies, of the families Sciaridae, Diadocidiidae, Ditomyiidae, Keroplatidae, Bolitophilidae and Mycetophilidae (order Diptera), sometimes placed in the superfamily Mycetophiloidea
http://psyche.entclub.org/pdf/58/58-073.pdf
Larve:http://ipm.ncsu.edu/current_ipm/06PestN ... fung5a.jpg
Adulte: http://culturesheet.org/pests:fungus_gnats
Serpent:http://ipm.ncsu.edu/current_ipm/06PestN ... usgnat.jpg
video:
http://www.youtube.com/watch?v=bDpUayCH ... re=related
http://www.youtube.com/watch?v=aC9iqtOm ... re=related