Breeding sites of Culicoides pachymerus Lutz in the Magdalena River basin, Colombia

Abstract

The breeding sites of Culicoides pachymerus are described for the first time in western Boyacá Province, Colombia, where Bloodsucking midges of the genus Culicoides Latreille belong to the family Ceratopogonidae. These insects have a long evolutionary history, with fossil records dating back 90 million years; at this time, they were already feeding on vertebrate blood (Borkent 2005). Culicoides midges have public health importance as vectors of viruses, nematodes and protozoans. In addition, their intensive biting is a significant nuisance and can cause dermatological problems when the insects are very abundant (Blanton & Wirth 1979, Borkent 2005. According to Borkent (2009), about 1,300 species of this genus have been described worldwide, of which 114 have been recorded in Colombia (Spinelli et al. 2009). Some of these species have been reported to cause problems in the Colombian Andes due to their high biting rates; Culicoides puracensis Wirth & Lee was reported as a pest in the uplands (páramo) of Puracé by Wirth and Lee (1967) and Culicoides pachymerus has been reported as a public health problem in western Boyacá since 1987 (Villareal 1998). Santamaría et al. (2008) reported peridomiciliary biting rates of up to 51.8 females/person/5 min for the latter region.As in other members of the family Ceratopogonidae, the life cycle of Culicoides midges consists of an egg stage, four larval instar stages, a pupal stage and an adult stage. The ecology and population dynamics of the larvae are key to understanding their patterns of abundance and the relationship of these patterns to environmental factors such as climate and habitat. Furthermore, control of the immature stages may play a significant part in pest and vector control. However, little is known about the microhabitats in which Culicoides larvae develop and immature stages have been described for only 238 (Borkent 2005) of the currently known species (Borkent 2009). Although the breeding sites of Culicoides are extremely variable, all are aquatic or semi-aquatic, including damp or wet decomposing vegetation, wet leaf packs, manure, many different types of phytotelmata, tree holes, swamps, ponds, lakes, streams and river margins, mangrove swamps, bogs and salt marshes (Borkent 2005).Despite the relatively wide neotropical distribution of C. pachymerus, which is found in Brazil, Colombia, Ecuador, Venezuela, Guatemala, El Salvador and Panamá (Forattini 1957, Wirth et al. 1988, the preferred breeding sites of this species have not been determined. The aim of the present study was to identify the microhabitats in which immatures of C. pachymerus occur.Sampling was carried out in three scattered rural dwelling areas (veredas) in the foothills of the eastern Cordillera of the Andes, which surrounds the central Magdalena River valley in Boyacá department: vereda Chizo Cuepar in the municipality of San Pablo de Borbur, vereda Santa Rosa in the municipality of Tunungua and vereda Topo Grande in the municipality of Pauna (Fig. 1).These rural dwelling areas were sele...

Abundance and diversity of Culicoides Latreille (Diptera: Ceratopogonidae) in southern Ontario, Canada

“…This could explain why temperature categories from 4 and 8 weeks prior to insect collection appeared to correlate to decreased abundance of C. biguttatus in Ontario in our study. Additional climatic factors also are important, as higher rainfall amounts can impact breeding and thus Culicoides abundance by lowering the temperature and raising humidity [53,55]. In our study, rainfall amounts 4 and 8 weeks prior to trapping significantly impacted the abundance of C. biguttatus and was associated with both a decrease in abundance [4 weeks prior (0.1-2.6 mm category), and 8 weeks prior (2.2-72.0 mm category)].…”

Effect of vertebrate feces on the attraction of Culicoides (Diptera: Ceratopogonidae) in an Amazonian mangrove

“…Because Culicoides are influenced by the intensity and frequency of rainfall and drought (Yee and Juliano 2012), we speculate that the greater abundance of individuals during the rainy season may be related to the more favorable conditions for the development of eggs and larvae, a consequence of the greater volume of fresh water in the mangroves and possibly of the lower salinity values, which favor the proliferation of these insects (Trindad and Gorayeb 2010). Frequent accumulation of rainwater is known to produce larval sites for C. pachymerus, C. iriartei, C. debilipalpis, C. leoni , and C. insignis (Carrasquilla et al 2010). Rain may also result in lower temperatures and increased humidity.…”

Acknowledging extraordinary women in the history of medical entomology

“…In addition, she studied triatomine vectors of Chagas disease and, for her contributions in this topic, a new species of triatomine bug, Belminus ferroae, was named in her honor in 2007 [ 370 – 372 ]. She also made important contributions to the biology and ecology of the family Ceratopogonidae, specifically concerning the genus Culicoides , in which some species are considered potential vectors of different microorganisms [ 373 ].…”