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Extensão da distribuição geográfica de Plecturocebus baptista (Pitheciidae, Primates) e uma possível zona híbrida com Plecturocebus hoffmannsi: implicações evolutivas e de conservação
Get PDFTiti monkeys (family Pitheciidae) are Neotropical primates highly diversified in morphology, ecology and genetics, with a wide geographic distribution, including the Amazon, Atlantic Forest, Cerrado, Pantanal and Caatinga. This diversity, together with knowledge gaps, generates uncertainties in titi monkey taxonomy and distribution. An example is Plecturocebus baptista, with only 14 occurrence records and an ill-defined distribution based on untested geographical barriers. Here, we report the occurrence of this species at a new locality outside its known range, across the Paraná-Urariá River, which was considered a distributional limit for the species. The new record implies an overlap of P. baptista with the range of P. hoffmannsi. We document the sighting of an apparent hybrid animal. Our observations suggest that i) the distribution of P. baptista needs to be reviewed, and ii) the evolutionary relationships between P. baptista and P. hoffmannsi may be more complex than previously assumed. Since both species share contiguous areas of potential hybridization, we question whether the two species arose via allopatric speciation.Macacos zogue-zogue (família Pitheciidae) são primatas neotropicais altamente diversificados em morfologia, ecologia e genética, com distribuição geográfica abrangente, incluindo a Floresta Amazônica, Mata Atlântica, Cerrado, Pantanal e a Caatinga. Essa diversificação, juntamente com lacunas de conhecimento, gera incertezas na taxonomia e distribuição das espécies. Um exemplo é Plecturocebus baptista, com apenas 14 registros de ocorrência e distribuição indefinida, baseada em barreiras geográficas não testadas. Aqui nós relatamos a ocorrência da espécie em uma nova localidade, fora de sua área conhecida de distribuição, que transpõe uma suposta barreira geográfica, o Rio Paraná-Urariá. O novo registro de P. baptista se sobrepõe à distribuição de P. hoffmannsi e, neste contexto, observamos um indivíduo aparentemente híbrido entre as duas espécies. Nossas observações sugerem que i) a distribuição de P. baptista necessita ser revisada, e ii) a relação evolutiva entre P. baptista e P. hoffmannsi pode ser mais complexa do que se pensava. Como ambas espécies compartilham áreas contínuas de potencial hibridização, questionamos se as duas espécies resultaram de especiação alopátrica
Testing main Amazonian rivers as barriers across time and space within widespread taxa
No full textAim: Present Amazonian diversity patterns can result from many different mechanisms and, consequently, the factors contributing to divergence across regions and/or taxa may differ. Nevertheless, the river-barrier hypothesis is still widely invoked as a causal process in divergence of Amazonian species. Here we use model-based phylogeographic analyses to test the extent to which major Amazonian rivers act similarly as barriers across time and space in two broadly distributed Amazonian taxa. Local: Amazon rain forest. Taxon: The lizard Gonatodes humeralis (Sphaerodactylidae) and the tree frog Dendropsophus leucophyllatus (Hylidae). Methods: We obtained RADseq data for samples distributed across main river barriers, representing main Areas of Endemism previously proposed for the region. We conduct model-based phylogeographic and genetic differentiation analyses across each population pair. Results: Measures of genetic differentiation (based on FST calculated from genomic data) show that all rivers are associated with significant genetic differentiation. Parameters estimated under investigated divergence models showed that divergence times for populations separated by each of the 11 bordering rivers were all fairly recent. The degree of differentiation consistently varied between taxa and among rivers, which is not an artifact of any corresponding difference in the genetic diversities of the respective taxa, or to amounts of migration based on analyses of the site-frequency spectrum. Main conclusions: Taken together, our results support a dispersal (rather than vicariance) history, without strong evidence of congruence between these species and rivers. However, once a species crossed a river, populations separated by each and every river have remained isolated—in this sense, rivers act similarly as barriers to any further gene flow. This result suggests differing degrees of persistence and gives rise to the seeming contradiction that the divergence process indeed varies across time, space and species, even though major Amazonian rivers have acted as secondary barriers to gene flow in the focal taxa. © 2019 John Wiley & Sons Lt
Encyclia, Epidendrum, or Prosthechea? Clarifying the Phylogenetic Position of a Rare Amazonian Orchid (Laeliinae-Epidendroideae-Orchidaceae)
No full textThe phylogenetic position of a rare orchid species, which was described by Mansfeld from the Brazilian Amazon, is discussed. Although originally described under Epidendrum despite having a column that is not fully adnate to the lip claw, a feature not common in this genus, Epidendrum apuahuense has been transferred to Encyclia and Prosthechea by other authors. About 90 yr after its description, we found a new population of this species in Brazil, which allowed us to study its taxonomy. A phylogenetic reconstruction was performed using nuclear (ITS rDNA) and plastid (matK exon, rpl32-trnL spacer, trnL intron, and trnL-trnF spacer) datasets, aiming to clarify the generic placement of this taxon. Our results strongly support keeping E. apuahuense under Epidendrum. We also neotypify this name, since the original specimens were destroyed and no illustration is available. The morphological affinities of E. apuahuense and allied taxa are discussed. © 2019 by the American Society of Plant Taxonomists
Caracterização Dos Estádios Ontogenéticos Pós Germinativos De Oenocarpus Bataua Mart. (Arecaceae)
No full textTwo new species of Zatypota (Hymenoptera: Ichneumonidae, Pimplinae) sharing the same host spider in Northeast Brazil
No full textSome polysphinctine wasps of the genus Zatypota complete their life cycles upon theridiid host spiders. The host range of these wasps is usually species-specific, although in some less common associations more than one wasp species interacts with the same host spider. Here we describe and illustrate the polysphinctine wasps Zatypota baezae sp. n. and Zatypota mulunguensis sp. n. (Hymenoptera: Ichneumonidae), both koinobiont ectoparasitoids of the spider Anelosimus baeza (Theridiidae). The two parasitoid wasps show the same development time (12 days) which was longer when compared with other parasitoid wasps Z. anomala Holmgren and Z. riverai Gauld (nine days). As described for other species of Zatypota and Hymenoepimecis, the second larval instar remains attached to the spider by the remains of the chorion and also by a rigid brownish-semitransparent membrane called a saddle. © 2019 Magnolia Press
Does water type influence diet composition in Amazonian manatee (Trichechus inunguis)? A case study comparing black and clearwater rivers
No full textWe assessed the feeding habits of the Amazonian manatee inhabiting blackwater (Negro River) and clearwater (Tapajós River) igapós (floodplains) using δ13C and δ15N of dentin and bone collagen from different ontogenetic classes (nursing calves, juveniles, and adults). Within an individual, the dentine δ13C and δ15N values did not vary with tooth position. Bones were more depleted in 13C and 15N compared to teeth, and the δ13C and δ15N in bone differed among classes. Food sources had δ13C values typical of algae, plants of C3 or C4 photosynthetic pathways. Mixing models showed that lactating females (inferred by isotopic values from nursing calves) had higher proportional consumption of C4 plants, while, for other adults, C3 plants were more frequent in the diet of manatees from both rivers. Juveniles had a mixed diet of C3 pants and C4 plants. We hypothesize the C4 plants signal of calves results from female movements to the floodplains of nearby whitewater rivers (várzeas), where C4 plants are abundant. Individuals from Tapajós may be more resident, as C3 plants and C4 plants are available during the flood pulse. Results demonstrate that manatee diets vary with ontogenetic classes and water typology. Preservation of habitats (igapó/várzea) is therefore required for the survival of Amazonian manatees. © 2019, Springer Nature Switzerland AG
Redescription of Polichnodes americana Giglio-Tos, 1898 (Orthoptera: Tettigoniidae) with a new record and habitat notes from Brazilian Amazon Rainforest
No full textIn this work it was made the redescription of male of Polichnodes americana including new traits as internal genitalia and morphology of stridulatory files. Also it was recorded for the first time the distribution of this species to Brazil, in Amazonas, and notes on habitat. Copyright © 2019 Magnolia Pres
FragSAD: A database of diversity and species abundance distributions from habitat fragments
Get PDFHabitat destruction is the single greatest anthropogenic threat to biodiversity. Decades of research on this issue have led to the accumulation of hundreds of data sets comparing species assemblages in larger, intact, habitats to smaller, more fragmented, habitats. Despite this, little synthesis or consensus has been achieved, primarily because of non-standardized sampling methodology and analyses of notoriously scale-dependent response variables (i.e., species richness). To be able to compare and contrast the results of habitat fragmentation on species’ assemblages, it is necessary to have the underlying data on species abundances and sampling intensity, so that standardization can be achieved. To accomplish this, we systematically searched the literature for studies where abundances of species in assemblages (of any taxa) were sampled from many habitat patches that varied in size. From these, we extracted data from several studies, and contacted authors of studies where appropriate data were collected but not published, giving us 117 studies that compared species assemblages among habitat fragments that varied in area. Less than one-half (41) of studies came from tropical forests of Central and South America, but there were many studies from temperate forests and grasslands from all continents except Antarctica. Fifty-four of the studies were on invertebrates (mostly insects), but there were several studies on plants (15), birds (16), mammals (19), and reptiles and amphibians (13). We also collected qualitative information on the length of time since fragmentation. With data on total and relative abundances (and identities) of species, sampling effort, and affiliated meta-data about the study sites, these data can be used to more definitively test hypotheses about the role of habitat fragmentation in altering patterns of biodiversity. There are no copyright restrictions. Please cite this data paper and the associated Dryad data set if the data are used in publications. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ
Criação de gado em Reservas Extrativistas: ameaça ou necessidade? O caso da Reserva Extrativista Tapajós-Arapiuns, Pará, Brasil
Get PDFThe development of livestock activities within Extractive Reserves in the Amazon has been the cause of controversies and inflammatory debates in the environmental area since the establishment of the SNUC Law. The history of the extractive movement had in the "draws" its main fight flag, as a strategy to fight the advance of the agricultural frontier. Regardless of the advances made by the movement, it is a fact that, over the last 20 years, cattle ranching has been the predominant use in deforested areas in the Amazon, including within the Extractive Reserves. This work sought to measure the current environmental impact caused by the conversion of forests to pasture formation in Federal Extractive Reserves, under the management of ICMBio, based on the analysis of the data provided by INPE/TerraClass Project, from the years 2004, 2010 and 2014, especially in the Tapajós-Arapiuns Extractive Reserve, one of the most populous in the state of Pará, besides promoting a socio-environmental analysis of this case in the face of the management challenges of the Protected Area-PA. Among the main results, it was observed that the contribution of pastures is below 3% of land use in 28 of the 30 terrestrial Resex in the Amazon. It is noteworthy that in the Tapajos-Arapiuns more than 90% of the area is preserved, with only 0.35% being pasture, supporting a herd of about 3,000 heads and an average of 14 heads per farmer. Another relevant aspect is related to the financial and social importance of the activity, since 60% of breeders reported that their herds supply the Resex communities, that is, they are marketed within the PA itself. It is concluded that the cattle raising activity in the Tapajós-Arapiuns Extractive Reserve was characterized as subsistence due to the size and modes of production identified and, finally, it is not the main vector of deforestation in the PA, and its contribution is practically irrelevant. © 2019 Universidade Federal do Parana. All rights reserved
Reproductive allocation by Amazon fishes in relation to feeding strategy and hydrology
No full textSeasonal environments favor the evolution of capital breeding, whereby reproduction uses surplus energy from resources acquired during an earlier period. Consequently, reproductive effort in capital breeders is expected to depend on traits associated with energy storage rather than environmental conditions at the time of reproduction. Based on a 15-year dataset, we investigate the effect of phenotype (body size and condition) and environmental conditions (intensity of hydrological seasons, predator density, and density of conspecifics) on fecundity three capital breeding fish species from the strongly seasonal Amazon River floodplain: Psectrogaster rutiloides, Triportheus angulatus, and Acestrorhynchus falcirostris. Fecundity of all three species was strongly correlated with phenotype and modulated by unfavorable environmental conditions during the period of reproduction, especially high density of conspecifics. Fecundity was negatively affected by the density of conspecifics for small females of A. falcirostris, and for T. angulatus females with poor body condition. Fecundity of P. rutiloides declined during periods of drought when density of conspecifics was highest. A clear tradeoff between quantity and quality of oocytes was found only for P. rutiloides. This study highlights that reproductive allocation of capital breeders in seasonal environments is strongly linked to environmental conditions before and during the reproductive period. © 2018, Springer Nature Switzerland AG