ABSTRACT
ABSTRACT The SISBIOTA-BRASIL was a three-year multimillion-dollar research program of the Brazilian government to document plants and animals in endangered/understudied areas and biomes in Brazil. Distributional patterns and the historical events that generated them are extensively unknown regarding Brazilian fauna and flora. This deficiency hinders the development of conservation policies and the understanding of evolutionary processes. Conservation decisions depend on precise knowledge of the taxonomy and geographic distribution of species. Given such a premise, we proposed to research the diversity of Diptera of the Brazilian western arc of Amazon, Cerrado, and Pantanal in the states of Mato Grosso, Mato Grosso do Sul, and Rondônia. Three important biomes of the South American continent characterize these Brazilian states: Amazon forest, Cerrado (Brazilian Savannah), and Pantanal. Besides their ecological relevance, these biomes historically lack intensive entomological surveys. Therefore, they are much underrepresented in the Brazilian natural history collections and in the scientific literature, which is further aggravated by the fact that these areas are being exponentially and rapidly converted to commercial lands. Our project involved over 90 collaborators from 24 different Brazilian institutions and one from Colombia among researchers, postdocs, graduate and undergraduate students, and technicians. We processed and analyzed nearly 300,000 specimens from ~60 families of Diptera collected with a large variety of methods in the sampled areas. Here, we provide a detailed overview of the genera and species diversity of 41 families treated. Our results point to a total of 2,130 species and 514 genera compiled and identified for the three states altogether, with an increase of 41% and 29% in the numbers of species and genera known for the three states combined, respectively. Overall, the 10 most species-rich families were Tachinidae, Cecidomyiidae, Tabanidae, Psychodidae, Sarcophagidae, Stratiomyidae, Bombyliidae, Syrphidae, Tephritidae, and Asilidae. The 10 most diverse in the number of genera were Tachinidae, Stratiomyidae, Asilidae, Mycetophilidae, Syrphidae, Tabanidae, Muscidae, Dolichopodidae, Sarcophagidae, and Chloropidae. So far, 111 scientific papers were published regarding taxonomic, phylogenetic, and biogeographical aspects of the studied families, with the description of 101 new species and three new genera. We expect that additional publications will result from this investigation because several specimens are now curated and being researched by specialists.
ABSTRACT
In this paper, the overall morphological differences between populations of Simulium subpallidum Lutz, 1909 are studied. Several studies found in the literature point to a relationship between the labral fans and body size and the habitat where blackfly larvae occur. However, other characteristics potentially related to the microhabitat, such as abdominal hook circlet morphology, which is used for larvae to fix themselves in the substratum, and thoracic prolegs morphology, which help larvae move in the substratum, were analyzed in three different populations of S. subpallidum, one of which occupied a faster flow. The results suggest phenotypic plasticity in S. subpallidum and a tendency toward larger structures in faster flows.
ABSTRACT
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.
Subject(s)
Animals , Humans , Male , Simuliidae/anatomy & histology , Simuliidae/classification , Brazil , Larva/anatomy & histology , Pupa/anatomy & histologyABSTRACT
We describe the abiotic factors affecting the distribution of black flies at a microhabitat scale, rather than at the regional scale usually present in the literature on the Neotropics. Black fly larvae were sampled from the Tocantins River and three tributaries, located in the Brazilian savanna (state of Tocantins, Brazil) during six bi-monthly sampling periods from October 2004-August 2005. At each sampling site, 15 random quadrats (30 x 30 cm) were sampled each period and for each quadrat were determined mean water velocity, predominant substrate type (rocks, riffle litter or riparian vegetation) and depth detrended correspondence analysis (DCA) was used to determine associations with current velocity, whereas correspondence analysis (CA) was used to estimate site specific current velocity associations. Canonical correspondence analysis (CCA) was used to identify general microhabitat associations. The CCA showed that most species had a trend towards riffle litter, except for Simulium nigrimanum associated with rocky substrate and Simulium cuasiexiguum associated with riparian vegetation. The DCA showed a well defined pattern of water velocity associations. The CA revealed that the species showed different speed associations from one site to another, suggesting different competitive pressures resulting in the occurrence of different realized niches.
Subject(s)
Animals , Biodiversity , Simuliidae/classification , Brazil , Population Density , Population Dynamics , Rivers , Tropical ClimateABSTRACT
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.
Subject(s)
Animals , Female , Male , Phylogeny , Simuliidae/classification , Simuliidae/anatomy & histology , Simuliidae/geneticsABSTRACT
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.