Cecidomyiidae - Bremia?
Bremia ? sp.
Size: 1.36 mm
Group Guild Status
Eutroglophile Predator? Common
The family Cecidomyiidae consists of very small, delicate flies, most of which are gall makers on plants. Other species feed on plants but do not make galls, some feed on fungi or decaying plant materials, there are a number of species that have predaceous larvae, and a few that are parasitoids (Gagné 1981). Some species in the family are of economic importance as agricultural pests.
We have identified at least three species of cecidomyiids in the cave, representing three genera in the tribe Cecidomyiidi. All of the species found in the cave are apparently associated with the bat guano deposits, and specimens were obtained from Berlese samples of the two main guano deposits, the Lunch Spot and the Maternity Roost. Cecidomyiids superficially resemble the dark-winged fungus gnats (Sciaridae; Lycoriella sp. and Plastosciara sp.) that are also associated with the guano deposits. Species of Bremia are usually associated with decaying materials, but probably more likely fill a predatory niche in the guano deposits (Gagné 2012). There are records of Bremia sp. recorded from caves in Arkansas, Georgia, and Missouri (Barnes et al. 2009; Reeves et al. 2000). These records do not mention an ecological association.
All of the cecidomyiid fly species in the cave are apparently tied to the annual bat guano deposits, and adults are most likely to be present while the bats are in residence and the guano deposits are “active”. The sampling dates for the materials we obtained from the Berlese samples support this hypothesis. Adults may occasionally be encountered in the cave later in the year, but are less likely to be found between October and March. Based on our limited data the population sizes of the three genera in the cave seem to be similar.
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