Abstract:
The biodiversity of insect trypanosomes is largely unknown, resulting in significant gaps in the understanding of pathogen
evolution. A culture-independent preliminary survey of trypanosomatid fauna was conducted for the parasites of Heteroptera
(Hemiptera) from several localities in Costa Rica. Trypanosomatid infections were detected by light microscopy of
smeared gut contents. Out of 257 insects representing 6 families, infections were found in 62 cases; cultures were obtained
for 29 new isolates. Gut material from infected hosts was preserved in the field using an SDS–EDTA buffer solution for
subsequent DNA extraction in the laboratory. PCR amplification of the trypanosomatid-specific spliced leader (SL) RNA
gene repeats was successful for 60 field samples. Eighteen distinct SL RNA typing units were identified in a set of 28
samples analysed in detail. Cluster analysis indicated that these typing units were unique and thus could represent new
species and, in some cases, new genera. This study reveals only a minor fraction of the trypanosomatid biodiversity, which
is anticipated to be high.
