A Preliminary list of Chironomidae (Diptera) present in Everglades National
Park.
Richard E. Jacobsen and Sue A. Perry
South Florida Natural Resources Center, Everglades National Park, Homestead,
FL
The midge family, Chironomidae, are typically the most species rich and
abundant macroinvertebrate group in freshwater ecosystems. They are a major
component in the Everglades food web, linking plant, algal, and microbial
production to higher trophic levels. Chironomid midges are abundant in a variety
of substrates including periphyton mats, and along with the Ceratopogonidae, are
the most important invertebrate group linking this algal resource to fish and other
fauna. Chironomid midges have also long been recognized as exceptional
indicators of nutrient enrichment (Rosenberg 1992, Lindegaard 1995), and are
increasingly being used to assess a variety of environmental disturbances (e.g.,
Williams et al. 2001). Because of their high species richness, the great diversity
of microhabitats that they occupy, and their wide collective tolerances for
physical and chemical conditions, studying chironomids alone can be as effective
as using a larger group of invertebrate taxa in bioassessment (King and
Richardson 2002, Ruse 2002).
Despite their important role in the Everglades ecosystem, and their extraordinary
usefulness in bioassessment research, the chironomid fauna of the Everglades was
almost completely unknown up until ten years ago. Prior to our collections, a
total of 60 species had been reported from the entire Everglades system, and only
2 species were documented for ENP. Over the past 4 1/2 years, we have made
extensive collections of chironomids, primarily by skimming the water surface for
their distinctive pupal exuviae, from a variety of habitats and localities in ENP
including: sawgrass and slough habitats in the Shark River Slough and Taylor
Slough basins, marl prairie and solution hole habitats in the Rocky Glades,
brackish waters along the Wilderness Waterway, canals, burrow pits, and
phytotelmata in the Park.
In this paper, we provide a list of 131 chironomid taxa collected within ENP,
highlight exciting taxonomic discoveries (e.g., Jacobsen and Perry 2000, 2002),
and point out taxonomic problems that require further study. We offer some
biogeographical observations on the fauna in ENP, and briefly discuss the
primarily environmental gradients (hydropattern, salinity) and factors (karst
landscapes, artificial habitats) that contribute to species richness in ENP. Finally,
we provide an updated total, and a projected estimate, of the total invertebrate
species richness in the Everglades system based upon integrating : (1) our
collections of Diptera from ENP [190 species], (2) records of Copepoda collected
in ENP by Dr. M. Cristina Bruno [38 specie ], and (3) the extensive list of
invertebrates collected by King (2001) from WCA-2A [approx. 270 species].
Literature Cited
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356 pp.
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Lindegaard, C. 1995. Classification of water-bodies and pollution. Pp. 385-404
In: P. D. Armitage, P. S. Cranston, and L. C. V. Pinder (eds.), The Chironomidae:
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Rosenberg, D. M. 1993. Freshwater biomonitoring and Chironomidae.
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Williams, D. D., A. I. Nesterovitch, A. F. Tavares, and E. G. Muzzatti. 2001.
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Richard E. Jacobsen, South FL Natural Resources Center, 40001 State Rd 9336,
Homestead, FL, 33034, Phone: 305-242-7800, Fax:305-242-7836,
rick_jacobsen@nps.gov.