Enclosed photographs show Scaptomyza graminum infested by Stigmatomyces sp. on abdominal tergites, and enlarged Stigmatomyces from ther same host. The parasite is ascomycete fungus of the order Laboulbeniales, familiarly named "laboulb". Six species of laboulbs (genera Arthrorhynchus and Stigmatomyces) from Diptera were published from Czech Republic by Rossi and Máca (2006) (DOWNLOAD), three more species (from Scaptomyza graminum [Drosophilidae] - see pictures, from Spelobia [Sphaeroceridae] and from Parydra[Ephydridae]) were found there recently. From most European countries there is no information about laboulbs, so that their geographic distribution there is not very clear. Tropical countries are rich on laboulbs but it is presumed that most species are still undiscovered. Only the "higher" diptera (Cyclorrhapha) are infested.
The biology of laboulbs is very interesting - see e. g. Majewski (1994) or Santamaria (1998), both quoted in the above mentioned paper. Preserved (dried or alcoholized) specimens of flies with laboulbs would be greatly acknowledged by W. Rossi (email) and/or Jan Máca (email).
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| The photograps, made by Dr. F. Weyda, are SEM ones, thus not "true-color" ones. The laboulbs are usually brown. |
References:
Majewski, T., 1994. Tha Laboulbeniales from Poland. - Polish Botanical Studies 7: 3-466.
Rossi, W. & J. Máca, 2006. Notes on the Laboulbeniales (Ascomycetes) from the Czech Republic. - Sydowia 58(1): 110-124.
Santamaria, S., 1998. Laboulbeniales, I. Laboubenia. - Flora Mycologica iberica 4: 1-186.
Nikita