Although correct taxonomy is paramount for disease control programs and epidemiological studies, morphology-based taxonomy of black flies is extremely difficult. In the present study, the utility of a partial sequence of the COI gene, the DNA barcoding region, for the identification of species of black flies from Mesoamerica was assessed. A total of 32 morphospecies were analyzed, one belonging to the genus Gigantodax and 31 species to the genus Simulium and six of its subgenera (Aspathia, Eusimulium, Notolepria, Psaroniocompsa, Psilopelmia, Trichodagmia). The Neighbour Joining tree (NJ) derived from the DNA barcodes grouped most specimens according to species or species groups recognized by morphotaxonomic studies. Intraspecific sequence divergences within morphologically distinct species ranged from 0.07% to 1.65%, while higher divergences (2.05%-6.13%) in species complexes suggested the presence of cryptic diversity. The existence of well-defined groups within S. callidum (Dyar & Shannon), S. quadrivittatum Loew, and S. samboni Jennings revealed the likely inclusion of cryptic species within these taxa. In addition, the suspected presence of sibling species within S. paynei Vargas and S. tarsatum Macquart was supported. DNA barcodes also showed that specimens of species that are difficult to delimit morphologically such as S. callidum, S. pseudocallidum Diaz Najera, S. travisi Vargas, Vargas & Ramirez-Perez, relatives of the species complexes such as S. metallicum Bellardi s.l. (e.g., S. horacioi Okazawa & Onishi, S. jobbinsi Vargas, Martinez Palacios, Diaz Najera, and S. puigi Vargas, Martinez Palacios & Diaz Najera), and S. virgatum Coquillett complex (e.g., S. paynei and S. tarsatum) grouped together in the NJ analysis, suggesting they represent valid species. DNA barcoding combined with a sound morphotaxonomic framework provided an effective approach for the identification of medically important black flies species in Mesoamerica and for the discovery of hidden diversity within this group.

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DNA barcoding of Neotropical black flies (Diptera: Simuliidae): Species identification and discovery of cryptic diversity in Mesoamerica

Costa Rica hosts an extraordinarily high biodiversity and is among the best studied neotropical countries. Insects represent the most diverse group of organisms, not only in terrestrial but also in aquatic, especially freshwater, habitats. Among the most diverse aquatic insect orders are the Trichoptera, Diptera and Coleoptera; although Ephemeroptera can locally also be very abundant and diverse. In Costa Rica, the taxonomically best known orders of aquatic insects are the caddisflies (Trichoptera), dragonflies (Odonata) and stoneflies (Plecoptera) and within the Dipterans, groups of medical importance have received special attention. The interest in aquatic insects has been constantly growing in Costa Rica over the past 10 years, but scientific publications are widely dispersed and often difficult to locate. Due to the importance of aquatic organisms in environmental impact studies and biomonitoring of freshwater habitats, there is an urgent need for comprehensive studies and publications that are locally available. In this sense, the present paper tries to give an overview on the state of knowledge and the literature published to date on the aquatic insects of Costa Rica, taking in account taxonomic, biological and ecological studies. Rev. Biol. Trop. 56 (Suppl. 4): 273-295. Epub 2009 June 30.

Aquatic insect diversity of Costa Rica: state of knowledge

Synopsis 135Introduction 136Material and Methods 138Acknowledgements 139Checklist to the Simuliidae of Belize 139Keys to Simuliidae species of Belize – females, males, pupae 139Species descriptions, distribution and biology:Simulium (Hemicnetha) earlei Vargas, Martinez Palacios & Diaz Najera 141Simulium (Hemicnetha) mexicanum Bellardi 144Simulium (Hemicnetha) pulverulentum Knab 146Simulium (Hemicnetha) virgatum Coquillett (complex) 148Simulium (Notolepria) gonzalezi Vargas & Diaz Najera 153Simulium (Psaroniocompsa) ganalesense Vargas, Martinez Palacios & Diaz Najera 155Simulium (Psilopelmia) callidum Dyar & Shannon 158Simulium (Psilopelmia) haematopotum Malloch 160Simulium (Psilopelmia) ochraceum Walker (complex) 164Simulium (Psilopelmia) quadrivittatum Loew 167Simulium (Psilopelmia) samboni Jennings 169Simulium (Simulium) metallicum Bellardi (complex) 171Conclusions 176References 177Maps, colour plates and figures 181Tables 244Material Examined 247Index 271With the increasing migration of people from Guatemala (where foci of human onchocerciasis exist) to Belize the probability of further introductions of individuals infected with this disease has increased. The present paper provides a comprehensive biosystematic revision of the Simuliidae of Belize, a prerequisite to any future surveys on simuliids if onchocerciasis becomes a public health problem. A key to the adults and pupae of the twelve species collected is provided together with full morphological descriptions of these species, discussions on their taxonomy, and summaries of their distribution and biology. Six new synonyms, a neotype and one lectotype are created. The distribution of Simuliidae in Belize in relation to physical factors is reviewed.

http://blackflies.info/sites/blackflies.info/files/u13/Simuliidae_of_Belize_2002.pdf

A biosystemic revision of the blackflies (Diptera: Simuliidae) of Belize, Central America.

We are concerned in this article with six intestinal parasitoses-the four main soiltransmitted helminthiases (ascariasis, trichuriasis, hookworm infection, and strongyloidiasis) and the two leading intestinal protozoan infections (amebiasis and giardiasis). These two groups of parasitoses depend on fecal contamination, but there is a significant epidemiologic difference between them. That is, the principal mechanisms for disseminating the four helminthiases involve fecal contamination of the soil and poor environmental sanitation; in contrast, dissemination of the protozooses results largely from poor personal hygiene, the infection being transmitted primarily from person to person via contaminated food, water, or hands. In view of the fact that the intestinal parasitoses are closely linked with underdevelopment and poverty, and since underdevelopment and poverty have diminished little if any over the years among vast portions of the Latin American population, this article is dedicated to examining the connections linking these high levels of intestinal parasitism to the low standards of living prevailing among many of the people of our countries.

Persistence of the endemic intestinal parasitoses in latin america

Over its fifty year history nearly twenty percent of the papers published in the Revista de Biologia Tropical have been about insects and arachnids. In the 1950's papers on arthropods of medical importance were dominant, in the 1960's there was a poliferation of papers on bees, and in more recent years the subjects have become incresingly diverse. In terms of nationality of contributing authors, the journal appears to have become increasingly international in later years.

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Fifty years of entomological publications in the Revista de Biología Tropical.

In the Western Hemisphere there are listed 61 species of black flies which are recorded as biting man in the Neotropical Region and 37 in the Nearctic Region. Five neotropical species, Simulium quadrivittatum, S. metallicum, S. callidum, S. baematopotum and S. paynei, were collected while biting rates in Costa Rica. The greatest biting rates in Costa Rica were at altitudes of 0 to 1500 m.

https://revista-ciencia-tecnologia.ucr.ac.cr/index.php/rbt/article/download/26090/26363

Bionomics of black flies (Diptera: simuliidae) in Costa Rica. I. Species biting man, with an epidemiological summary for the Western Hemisphere

Single stool specimens were collected from 848 individuals from three rural communities of Paracito, El Naranjo and Palmira, Costa Rica. Examination by the F. E. sedimentation technique revealed 7 species of helminths and 11 species of protozoa. Over 95% of the 848 persons examined were parasitized, 83.5% with worms and 86% with protozoa. Whipworm, T. trichiufa, A. lumbricoides and hookworms were the most common worms encountered. Entamoeba histolytica occurred in about 40% of the people while Giardia lamblia was found in 21.7%. Dientamoeba fragilis was not encountered due to the method of examining the stools.

J. C. Swartzwelder

Papers

Bionomics of black flies (Diptera: simuliidae) in Costa Rica. I. Species biting man, with an epidemiological summary for the Western Hemisphere

A survey of three Costa Rican communities for intestinal parasites