Abstract
Background
Diversity and distribution of Neotropical aquatic insects is still poorly known, with
many species to be recorded and many others to be described, due to the small number
of taxonomists and sparse faunistic studies. This knowledge is especially poor in
the Caatinga Domain in Northeastern Brazil, even though, this region may have played
an important historical role in the spatial evolution of faunas of forested areas
in northern South America.
New information
Aquatic insect checklists of 96 species from Parque Nacional de Ubajara (Ceará State,
Brazil) and 112 species from Parque Nacional de Sete Cidades (Piauí State, Brazil)
are presented, representing the following taxa:
Elmidae
,
Epimetopidae
,
Hydrophilidae
, and
Torridincolidae
(
Coleoptera
),
Hemerodromiinae
(
Diptera
:
Empididae
),
Ephemeroptera
,
Gerromorpha
and
Nepomorpha
(
Hemiptera
),
Odonata
,
Plecoptera
, and
Trichoptera
. Because of the scarce number of biological inventories in Northeastern Brazil, several
new distributional records (of species, genera, and families) for Brazil, Northeastern
Brazil, and Ceará and Piauí states are provided. In addition, several undescribed
species were detected, being 26 from Ubajara and 20 from Sete Cidades. Results represent
a significant increase to the known fauna of these states, ranging from 13%-70% increase
for Ceará and 41% to 91% increase for Piauí. Although both parks are relatively close
to each other and within the Caatinga domain, their aquatic fauna display a very high
complementarity (89% species), possibly due to structural differences of water bodies
sampled in each park. Rarefaction curves based on quantitative light trap samples
suggest a much higher expected species richness of aquatic insects at Sete Cidades
than at Ubajara National Park. Discussion on biogeographical affinities of this sample
of the Caatinga fauna is provided.