Simulium (Chirostilbia) brunnescens (Diptera: Simuliidae) - new species from the Brazilian cerrado, Manso Dam, state of Mato Grosso, Brazil

A new species of Simuliidae, Simulium (Chirostilbia) brunnescens, was discovered at Chapada dos Guimarães, state of Mato Grosso, Brazil, and nearby municipalities (Paranatinga, Rosário do Oeste and Nobres). This species is described here based on the adults, pupae and larvae. This species is closely related to Simulium (C.) subpallidum Lutz, but could be differentiated in all stages: females, leg colour pattern and frontal dilatation size; males, gonostyle shape; pupae, number of gill filaments; larvae, body size and colour, postgenal cleft, ratio between antenna and stalk of labral fan.

The phylogeny of Simulium (Chirostilbia) (Diptera: Simuliidae) and perspectives on the systematics of the genus in the Neotropical Region

Recently, knowledge of Neotropical Simuliidae has been accumulating quickly. However, information about supra-specific relationships is scarce and diagnoses of Simulium subgenera are unsatisfactory. To investigate the relationships among Simulium (Chirostilbia) species and test the subgenus monophyly, we performed a cladistic analysis. The ingroup included all species of this subgenus and the outgroup included representatives of the 17 species groups of Neotropical Simulium and three Holarctic species. The study was based on a data matrix with 31 terminal taxa and 45 morphological characteristics of adult, pupa and larva. The phylogenetic analysis under equal weights resulted in eight most-parsimonious trees (length = 178, consistency index = 34, retention index = 67). The monophyly of the S. (Chirostilbia) was not supported in our analysis. The Simulium subpallidum species group was closer to Simulium (Psilopelmia) and Simulium (Ectemnaspis) than to the Simulium pertinax species group. Additionally, we describe the three-dimensional shape of the terminalia of male and female of Simulium (Chirostilbia) for the first time and provide comments about the taxonomic problems involving some species of the subgenus: Simulium acarayense, Simulium papaveroi, S. pertinax, Simulium serranum, Simulium striginotum and S. subpallidum.

Simulium (Psilopelmia) virescens, a new black-fly species (Diptera: Simuliidae) from the southwestern region of the state of Bahia, Brazil

The last-instar larva, pupa, male and female of Simulium virescens sp. nov. are described and illustrated. This species has a peculiar larva, which has an elongated head capsule and light-green colour. The first thoracic segment has tubercle on its dorsal region and the third thoracic segment has one pair of tubercles; the first to the fourth abdominal segments have one pair of tubercles on each segment. Until now this new species had only been collected at the type locality, which is on the middle stretch of the Correntina River in the southwestern portion of the state of Bahia, Brazil. Females were voraciously biting humans during the field work. This new species represents the second species of Simulium(Psilopelmia) in Brazil and the first registered outside of the Brazilian Amazon Region.

Simulium (Inaequalium) marins, a new species of black fly (Diptera: Simuliidae) from inselbergs in Brazil

A new species of black fly, Simulium (Inaequalium) marins (Diptera: Simuliidae), is described based on the male, female, pupa and larva. This new species was collected from two localities: a small stream on the Pico dos Marins, a high mountain with granite outcrops in Piquete County, state of São Paulo, and in a small stream in the Serra dos Órgãos National Park, state of Rio de Janeiro, Brazil.

Larval ontogeny and morphological variations of Psaroniocompsa incrustata (Lutz) (Diptera: Simuliidae) in the State of Rio Grande do Norte, Northeastern Brazil / Ontogenia larval e variações morfológicas de Psaroniocompsa incrustata (Lutz) (Diptera: Simuliidae) do Rio Grande do Norte

Psaroniocompsa incrustata (Lutz) is an antropophilic species widely distributed in Central and South America. It is the vector of Onchocerca volvulus in a Brazilian focus and has been considered a plague in several areas of this country. The objective of this study was to determine the number of larval instars and to describe the morphological variations and teratologies of a population of P. incrustata from the Pium river, Rio Grande do Norte State. The number of larval instars was determined measuring the head capsule lateral length of 3,164 larvae. The larval instars were determined using the measurement frequency distribution, Student's t-test, the Dyar and Crosby growth rules. Eight larval instars were determined for P. incrustata. A high rate of teratologies (9.6 percent) in the hypostomium and variations in the lateral serrations and the latero-mandibular process were found.

Psaroniocompsa incrustata (Lutz) é uma espécie antropofílica amplamente distribuída na América Central e do Sul. No foco brasileiro de oncocercose é considerada vetora de Onchocerca volvulus, sendo praga em outras regiões do país. Este estudo teve por objetivos determinar o número de estádios larvais e descrever as variações morfológicas e teratologias de uma população de P. incrustata do rio Pium, Rio Grande do Norte. O número de estádios larvais dessa espécie foi determinado medindo o comprimento lateral da cápsula cefálica de 3.164 larvas. Os estádios larvais foram determinados usando distribuição de frequências, teste-t de Student, regra de Dyar e de crescimento de Crosby. Foram identificados oito estádios larvais para P. incrustata. Foi encontrada uma elevada taxa de teratologias (9,6 por cento) no hipostômio, variações nas serrações laterais e no processo látero-mandibular.

Local distribution of blackfly (Diptera, Simuliidae) larvae in two adjacent streams: the role of water current velocity in the diversity of blackfly larvae / Distribuição local de larvas de simulídeos (Diptera, Simuliidae) em dois rios adjacentes: O papel da velocidade da correnteza na diversidade de larvas de simulídeos

This study aimed to evaluate the influence of water velocity speed on the local distribution and taxocenosis structure of blackfly larvae. The larvae were collected from two adjacent streams located in the municipality of Angra dos Reis (RJ): Caputera River and one of its tributaries. Riffle litter patches were sampled randomly using a 30 x 30 cm quadrat. Four blackfly species were found: Simulium incrustatum s. l. Lutz, 1910; Simulium (Inaequalium) sp. ; Simulium pertinax s. l. Kollar, 1832 and Simulium subpallidum s. l. Lutz, 1909. Among these species, Simulium pertinax s. l. was clearly associated with higher water current speeds, while Simulium subpallidum s. l. showed association with lower water velocities, and Simulium (Inaequalium) sp. had a relatively constant distribution along the water current gradient.

Este estudo teve como objetivo avaliar, nos criadouros de simulídeos, a influência da velocidade da água sobre a ocorrência de suas larvas e estrutura de suas taxocenoses. Para obtenção da amostragem foram utilizados "quadrats" de madeira distribuídos aleatoriamente no rio Caputera e um de seus tributários. Foram encontradas quatro espécies: Simulium incrustatum sl. Lutz, 1910; Simulium (Inaequalium) sp. ; Simulium pertinax sl. Kollar, 1832 e Simulium subpallidum sl. Lutz 1909. S. (Inaequalium) sp. teve uma distribuição quase constante ao longo do gradiente de correnteza. S. pertinax se mostrou fortemente associada às velocidades mais altas de correnteza, enquanto que S. subpallidum se mostrou associado às velocidades mais baixas.

Larval description of Simulium (Notolepria) cuasiexiguum and Simulium (Chirostilbia) obesum and new records of black fly species (Diptera: Simuliidae) in the States of São Paulo and Minas Gerais, Brazil

We describe the larval stage of Simulium cuasiexiguum Shelley, Luna Dias, Maia-Herzog & Lowry and Simulium obesum Vulcano and provide new distribution records of four black fly species in the State of São Paulo (Simulium cuasiexiguum, Simulium metallicum s.l. Bellardi, Simulium stellatum Gil Azevedo, Figueró & Maia-Herzog and Simulium oyapockense s.l. Floch & Abonnenc) and three species in the State of Minas Gerais (Simulium duodenicornium Pepinelli, Hamada & Trivinho-Strixino, Simulium obesum and Lutzsimulium pernigrum Lutz).

Neste manuscrito são descritos os estágios larvais de Simulium cuasiexiguum Shelley, Luna Dias, Maia-Herzog & Lowry e Simulium obesum Vulcano. São fornecidos ainda novos registros para quatro espécies de borrachudos para o estado de São Paulo (Simulium cuasiexiguum, Simulium metallicum s.l. Bellardi, Simulium stellatum Gil Azevedo, Figueró & Maia-Herzog e Simulium oyapockense s.l. Floch & Abonnenc) e de três para Minas Gerais (Simulium duodenicornium Pepinelli, Hamada & Trivinho-Strixino, Simulium obesum e Lutzsimulium pernigrum Lutz).

Cytotaxonomy of Simulium cauchense Floch & Abonnenc and Simulium quadrifidum Lutz (Diptera: Simuliidae) in Brazilian Amazonia

Simulium cauchense Floch & Abonnenc and Simulium quadrifidum Lutz are widely distributed in the Amazon region and are morphologically similar at the larval and pupal stages. Chromosomally, these species are readily distinguished by the position of the nucleolar organizer, which is in the short arm of chromosome I in S. cauchense and in the long arm of chromosomes III in S. quadrifidum. They also differ by three fixed inversions. Sex chromosomes are undifferentiated in both species. Chromosomal resolution of the two species allowed us to evaluate four structural features previously used as diagnostic aids at the larval stage. Characters that distinguish larvae of the two species are the number of branches and branching patterns of the dorsal abdominal setae and the dark band on each primary fan. Branching patterns of the gill histoblasts were often diagnostic, with S. quadrifidum exhibiting more proximal branching and S. cauchense more distal branching. Sites where both species occurred sometimes had larvae with one petiole branching proximally and the other distally; in these cases examination of the chromosomes permitted assignment of the specimen to species. Pigmentation patterns of larvae, on the other hand, are highly variable. Color typically is sex linked in both species.

New records of Simuliidae (Diptera, Nematocera) in the State of São Paulo, Brazil

Adult and immature Simuliidae were studied in 31 streams of 8 regions of the State of São Paulo. Among the 25 species collected, seven are new records for the State of São Paulo, and one of them, Simulium shewellianum Coscarón, 1985 for Brazil as well.

Black flies (Diptera: Simuliidae) of French Guiana: cytotaxonomy and a preliminary list of species

The objectives of the present study were to broaden the survey of simuliid species in French Guiana and to cytologically analyze the species in the Simulium perflavum species group. Twelve species of Simulium were collected from which S. goeldii, S. quadrifidum, S. trombetense, S. near incrustatum, S. metallicum (s.l.) sp1, S. metallicum (s.l.) sp2 and S. ochraceum (s.l.) are reported for the first time for this region. The only species collected in the S. perflavum group was S. rorotaense; 34 larvae of this species were cytologically analyzed, all of which had the standard sequence. S. metallicum (s.l.), S. ochraceum (s.l.), S. guianense (s.l.) and S. oyapockense (s.l.) are involved with transmission of onchocerciasis in Central and South America, however, in French Guiana these species were not found biting humans during the sampling period. With the few collections made during this study, we increase the number of simulid species known in French Guiana from 6 to 13. It is clear that more simuliid species can be expected to be found when more sampling is done, including collections in other ecoregions in French Guiana

Morphometric comparison of Simulium perflavum larvae (Diptera: Simuliidae) in relation to season and gender in Central Amazônia, Brazil

Number of larval instars, age structure and environmental effects on these parameters represent basic information in the study of insect population biology. When species have economic importance, this information is essential in order to choose the best period to apply different control methods and to determine the stages of the life cycle of the insect that are most susceptible to each treatment. The family Simuliidae has many species of medical/veterinary importance in the world, and some studies in the temperate region have suggested that the number of larval instars and the larval size can vary according to the season, gender and some environmental factors, such as temperature and diet. This study, with the zoophilic species Simulium perflavum Roubaud, is the first in the Neotropics observing some of these factors and will serve as a template for other species of medical importance in the region. S. perflavum larvae were collected in five streams in Central Amazônia (Manaus and Presidente Figueiredo counties, State of Amazonas), in Sept./Oct. 1996 (dry season) and Feb./Mar. 1997 (rainy season). These larvae were measured (lateral length of head capsule and width of cephalic apodema) to determine the number of larval instars (n=3985), to compare the larval size between seasons and genders (last and penultimate larval instars, n=200). Seven larval instars were determined for this species using frequency distributions, t-tests and CrosbyÝs growth rule. Significant differences were not detected (t-test, p>0.05) in larval size between seasons and genders. Our results differ from some found in temperate regions suggesting that in the Neotropical region the larval size in different seasons and different genders remains constant, although some environmental parameters, such as diet, change depending on the season

Simulium cuasiexiguum, a new blackfly species (Diptera: Simuliidae) from the Minaçu area in the State of Goiás, Central Brazil

During studies of Simuliidae at a suspected new focus of human onchocerciasis in central Brazil a new species of Simulium was found. Full descriptions of the adults and pupae of this species, S. cuasiexiguum, are described here, its affinities to closely related species in the subgenus Notolepria are discussed and its distribution in Brazil recorded

A new species of Simulium (Diptera: Simuliidae) from open areas in Central Amazonia, Brazil

The larva, pupa, male and female of Simulium daltanhani n.sp. are described and illustrated. This species shares diagnostic characteristics with Simulium quadrifidum Lutz, Simulium cauchense Floch & Abonnenc, Simulium brevifurcatum Lutz and Similium siolii Py-Daniel. It was collected in three countries (Manaus, Presidente Figueiredo and Itacoatiara) in the State of Amazonas, Brazil. Its habitat includes streams in disturbed, open areas where the forest has been cut for road constuction; it was not collected in adjacent forested streams, suggesting that it colonizes disturbed habitats. The larval subesophageal ganglion i discussed as a useful character, when pigmented, to distinguish this species within a limited geographic area.

Revisión de la familia simuliidae (Diptera, Nematocera) en Venezuela / Review of the simuliidae family (Diptera, Nematocera) in Venezuela

En la presente revisión, se hace una exposición cronológica de los estudios sobre taxonomía y sistemática de simúlidos que se han llavado a cabo hasta el presente en Venesuela. Se acompaña un mapa indicando la distribución geográfica de los vectores y fondos de oncocercosis y mansonelosis en el país. Del género Simulium Latreille, 1902, se sañalan 51 especies y 7 del género Gigantodax Enderlein, 1925. Se presenta una lista sobre la distribución geográfica por entidades de las 59 especies de la familia Simuliidae Schiner, 1864, sañalando un total de 14 sinonimos en Venezuela

Simuliidae (Diptera: Culicomorpha) no Brasil: V. Sobre o Simulium (chirostilbia) friedlanderi sp.n. e revisäo do Simulium (C.) laneportoi Vargas, 1941 / Simuliidae (Diptera: Culicomorpha) in Brazil: V. On Simulium (Chirostilbia) friedlanderi sp.n. and review of Simulium (C.) laneportoi Vargas, 1941

Uma espécie nova, Simulium friedlanderi, do subgênero Simulium (Chirostilbia) Enderlein é descrita, sendo a mesma procedente do norte da Província Hidrogeológica do Centro-Oeste, subprovíncia Alto Paraguai. Simulium (Chirostilbia) laneportoi Vargas, 1941 é revisada, sendo o Simulium (C.) dekeyseri Shelley e Py-Daniel, 1981 colocada em sua sinonimia, e apresentando uma distribuiçäo geográfica tanto no norte da Província Hidrogeológica do Centro-Oeste, subprovíncia Alto Paraguai, como no sudeste da Província Hidrogeológica do Escudo Central. Säo apresentadas chaves diferenciativas para larvas e pupas do grupo pertinax