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Vol. 51 No. 8, 2012
Spatial Variations in Water Beetle Communities in Arid and
Semi-Arid Patagonian Wetlands and Their Value as Environmental
Indicators
Luis
B. Epele* and Miguel Archangelsky
CONICET-Laboratorio
de Investigaciones en Ecología y Sistemática Animal (LIESA), Univ.
Nacional de la Patagonia, Sede Esquel, Sarmiento 849, Esquel 9200,
Chubut, Argentina
Luis B. Epele and Miguel Archangelsky
(2012) To evaluate spatial variations in aquatic beetle
assemblages, 26 Patagonian ponds were sampled during late spring
(Dec.). The hydroperiod, hydrology, abiotic features, precipitation,
aridity, and aquatic plant richness of the study sites differed.
Fifteen physicochemical features were measured, and aquatic plants were
collected to determine taxonomic richness. Sampling of the 26 ponds
produced 21 aquatic beetle taxa in 6 families. All aquatic beetles
(adults and larvae) were assigned to functional feeding groups. A
canonical correspondence analysis (CCA) was run to assess relationships
between aquatic beetle assemblages and environmental variables. Of the
variance in aquatic beetle taxa abundances, 23% was accounted for by
the 1st 3 ordination axes. Moreover, the 1st 2 canonical axes
respectively accounted for 38.2% and 28.4% of the variations
attributable to environmental variables (i.e., annual precipitation,
elevation, pond area, aquatic plant richness, pH, and conductivity),
with conductivity and elevation being the most important. A parsimony
analysis was performed to establish which species could define and/or
group some of the communities (with sampling sites treated as taxa and
species treated as characters). Results of the parsimony analysis
suggested that some taxa (Haliplus
subseriatus, Gymnochthebius
sp., Enochrus darwini, Cyphon sp., Luchoelmis sp., and Rhantus validus) were useful in defining
some ponds or groups of ponds. These species can be used as indicators
since beetle distributions are not considered to randomly occur. Our
findings show that aquatic beetle assemblages
can be utilized for wetland conservation planning since in arid and
semiarid Patagonia, they are important as water reservoirs and for
cattle rearing.
Key words: Mallines, Ponds, Coleoptera,
Indicator species, Parsimony analysis.
*Correspondence: E-mail:luisbepele@hotmail.com
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