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1.
Zootaxa ; 5415(1): 181-192, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38480208

RESUMO

The South American palpimanid genus Fernandezina Birabn currently comprises 15 described species, all known from epigean environments. Representatives of Fernandezina are easily recognized by the unexpanded femora I in both sexes and by the dorsally extended opisthosomal scutum in males. Herein, F. fernandoi sp. nov. is described based on males and females from hypogean environments and F. angeloi sp. nov. is described based on a single male from a nearby epigean environment, both in Brazil. Additionally, we provide an identification key for the species of the genus.


Assuntos
Aranhas , Feminino , Masculino , Animais , Brasil , Distribuição Animal , Cavernas , Ecossistema
2.
Zootaxa ; 5399(5): 517-539, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38480122

RESUMO

The Caatinga is a nucleus of seasonally dry tropical forest (SDTF) known as a hotspot of diversification and endemism. Despite its importance, this biome is still insufficiently sampled, resulting in extensive knowledge gaps regarding its species richness and composition. In this study we report two species of Xenoctenidae that are endemic to, and widely distributed in the Caatinga. We redescribe and illustrate Odo vittatus (Mello-Leito, 1936), the only xenoctenid species previously known from the Caatinga. We transfer this species to Xenoctenus Mello-Leito,1938, a genus currently known from six species restricted to Argentina, Bolivia, and Colombia. We also newly describe the male of Xenoctenus vittatus comb. nov. and provide new records of this species, which was hitherto known only from the type-locality, throughout the Caatinga and nearby semiarid vegetation formations. We also describe and illustrate a new species, Xenoctenus kaatinga sp. nov., based on males and female specimens collected throughout the Caatinga. Additionally, we propose diagnostic characters for Xenoctenus and redescribe the type-species, X. unguiculatus.


Assuntos
Aranhas , Animais , Feminino , Masculino , Brasil , Ecossistema , Florestas
3.
Zootaxa ; 4979(1): 131146, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34187009

RESUMO

Zootaxa published more than a thousand papers on Araneae from 2002 to the present, including descriptions of 3,833 new spider species and 177 new genera. Here we summarise the key contributions of Zootaxa to our current knowledge of global spider diversity. We provide a historical account of the researchers that have actively participated as editors, and recognize the more than 1,000 reviewers without whom none of this would have been possible. We conduct a simple analysis of the contributions by authors and geographic region, which allows us to uncover some of the underlying trends in current spider taxonomy. In addition, we examine some of the milestones in twenty years of spider systematic research in Zootaxa. Finally, we discuss future prospects of spider taxonomy and the role that Zootaxa and its younger sister journal Megataxa will play in it. We would like to dedicate this contribution to the memory of Norman I. Platnick, a crucial figure in the advancement of spider systematics.


Assuntos
Aranhas/classificação , Animais , Biodiversidade , Publicações Periódicas como Assunto
4.
Syst Biol ; 69(6): 1122-1136, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32170955

RESUMO

Vicariance and dispersal events, combined with intricate global climatic history, have left an imprint on the spatiotemporal distribution and diversity of many organisms. Anelosimus cobweb spiders (Theridiidae), are organisms ranging in behavior from solitary to highly social, with a cosmopolitan distribution in temperate to tropical areas. Their evolutionary history and the discontinuous distribution of species richness suggest that 1) long-distance overwater dispersal and 2) climate change during the Neogene (23-2.6 Ma), may be major factors in explaining their distribution and diversification. Here, we test these hypotheses, and explicitly test if global Miocene/Pliocene climatic cooling in the last 8 Ma affected Anelosimus radiation in parallel in South America and Madagascar. To do so, we investigate the phylogeny and spatiotemporal biogeography of Anelosimus through a culmination of a 20-year comprehensive global sampling at the species level (69 species, including 84% of the known 75 species worldwide, represented by 268 individuals) using nucleotide data from seven loci (5.5 kb). Our results strongly support the monophyly of Anelosimus with an Oligocene ($\sim $30 Ma) South American origin. Major clades on other continents originate via multiple, long-distance dispersal events, of solitary or subsocial-but not social-lineages, from the Americas. These intercontinental dispersals were to Africa, Madagascar (twice), and SE Asia/Australasia. The early diversification of Anelosimus spiders coincides with a sudden thermal increase in the late Oligocene ($\sim $27-25 Ma), though no causal connection can be made. Our results, however, strongly support the hypothesis that global Neogene climatic cooling in the last 8 Ma drove Anelosimus radiation in parallel in South America and Madagascar, offering a rare empirical evidence for diversification of a socially diverse group driven by an interplay between long-distance dispersal and global Neogene climatic changes. [Cobweb spiders; diversification; global biogeography; long-distance dispersal; molecular phylogenetics; neogene climate changes; sociality; vicariance.].


Assuntos
Distribuição Animal/fisiologia , Biodiversidade , Filogenia , Aranhas/classificação , Aranhas/fisiologia , Animais , Mudança Climática
5.
Zootaxa ; 4567(1): zootaxa.4567.1.2, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-31716437

RESUMO

The genus Runcinioides is revised, including the redescription of R. argenteus Mello-Leitão, 1929 and R. litteratus (Piza, 1933). The male of R. litteratus is described and illustrated for the first time and Misumenops paranensis (Mello-Leitão, 1932) is here considered a junior synonym of R. argenteus. The known geographic distribution of both species is expanded with the inclusion of new occurrence data. Runcinioides pustulatus Mello-Leitão, 1929 and Runcinioides souzai Soares, 1942 are not related to the other species of the genus, and provisionally considered as incertae sedis.


Assuntos
Braquiúros , Distribuição Animal , Animais , Masculino
6.
Sci Rep ; 9(1): 6355, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015555

RESUMO

Traditional conservation techniques for mapping highly biodiverse areas assume there to be satisfactory knowledge about the geographic distribution of biodiversity. There are, however, large gaps in biological sampling and hence knowledge shortfalls. This problem is even more pronounced in the tropics. Indeed, the use of only a few taxonomic groups or environmental surrogates for modelling biodiversity is not viable in mega-diverse countries, such as Brazil. To overcome these limitations, we developed a comprehensive spatial model that includes phylogenetic information and other several biodiversity dimensions aimed at mapping areas with high relevance for biodiversity conservation. Our model applies a genetic algorithm tool for identifying the smallest possible region within a unique biota that contains the most number of species and phylogenetic diversity, as well as the highest endemicity and phylogenetic endemism. The model successfully pinpoints small highly biodiverse areas alongside regions with knowledge shortfalls where further sampling should be conducted. Our results suggest that conservation strategies should consider several taxonomic groups, the multiple dimensions of biodiversity, and associated sampling uncertainties.


Assuntos
Biodiversidade , Modelos Teóricos , Biota , Brasil , Conservação dos Recursos Naturais , Geografia
8.
Sci Rep, v. 9, 6355, abr. 2019
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: bud-2736

RESUMO

Traditional conservation techniques for mapping highly biodiverse areas assume there to be satisfactory knowledge about the geographic distribution of biodiversity. There are, however, large gaps in biological sampling and hence knowledge shortfalls. This problem is even more pronounced in the tropics. Indeed, the use of only a few taxonomic groups or environmental surrogates for modelling biodiversity is not viable in mega-diverse countries, such as Brazil. To overcome these limitations, we developed a comprehensive spatial model that includes phylogenetic information and other several biodiversity dimensions aimed at mapping areas with high relevance for biodiversity conservation. Our model applies a genetic algorithm tool for identifying the smallest possible region within a unique biota that contains the most number of species and phylogenetic diversity, as well as the highest endemicity and phylogenetic endemism. The model successfully pinpoints small highly biodiverse areas alongside regions with knowledge shortfalls where further sampling should be conducted. Our results suggest that conservation strategies should consider several taxonomic groups, the multiple dimensions of biodiversity, and associated sampling uncertainties.

9.
Sci Rep ; 9: 6355, 2019.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib15972

RESUMO

Traditional conservation techniques for mapping highly biodiverse areas assume there to be satisfactory knowledge about the geographic distribution of biodiversity. There are, however, large gaps in biological sampling and hence knowledge shortfalls. This problem is even more pronounced in the tropics. Indeed, the use of only a few taxonomic groups or environmental surrogates for modelling biodiversity is not viable in mega-diverse countries, such as Brazil. To overcome these limitations, we developed a comprehensive spatial model that includes phylogenetic information and other several biodiversity dimensions aimed at mapping areas with high relevance for biodiversity conservation. Our model applies a genetic algorithm tool for identifying the smallest possible region within a unique biota that contains the most number of species and phylogenetic diversity, as well as the highest endemicity and phylogenetic endemism. The model successfully pinpoints small highly biodiverse areas alongside regions with knowledge shortfalls where further sampling should be conducted. Our results suggest that conservation strategies should consider several taxonomic groups, the multiple dimensions of biodiversity, and associated sampling uncertainties.

10.
Zootaxa ; 4415(3): 423-451, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30313610

RESUMO

The spider genus Mecynogea comprises nine species distributed predominantly in the Neotropics. Although the genus has been revised recently, several aspects of its taxonomy and morphology are still unresolved. In this paper, Mecynogea infelix (Soares Camargo, 1948) is removed from the synonymy of Mecynogea bigibba Simon, 1903 and redescribed. Mecynogea chavona Levi, 1997 is considered a junior synonym of M. infelix. The male of Mecynogea buique Levi, 1997 is described and illustrated for the first time. The internal female genitalia of M. buique and M. infelix is described and shown to be remarkably different from each other. We show that part of the intraspecific variation reported previously for the female of M. infelix is the result of epigynum mutilation, possibly during copulation. We also report the presence of an internal branch on the terminal apophysis in the male palp of Mecynogea species. This structure, in some species visible only on the expanded bulb, is shown to be present in all Cyrtophorinae. The internal branch of the terminal apophysis, together with the conductor fully fused to the tegulum, is herein proposed as synapomorphic for the subfamily. Mecynogea lemniscata (Walckenaer, 1841) is recorded for the first time in Bolivia. We also provide new Brazilian records for M. infelix, M. bigibba, M. buique, M. eryhtromela (Holmberg, 1876), and M. sucre Levi, 1997. Mecynogea carvalhoi Mello-Leitão, 1944, currently considered a nomen dubium, is revalidated, transferred to Argiope Audouin, 1826, redescribed and illustrated for the first time.


Assuntos
Aranhas , Distribuição Animal , Animais , Bolívia , Brasil , Copulação , Feminino , Masculino
12.
Zootaxa ; 4527(1): 37-48, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30651474

RESUMO

Four new species of Oecobiidae Blackwall, 1862 are described based on specimens collected in the Madagascan provinces of Toliara, Mahajanga and Antsiranana. Oecobius kowalskii sp. nov. and Paroecobius skipper sp. nov. are described based on male and female specimens. Paroecobius rico sp. nov. and Paroecobius private sp. nov. are described based only on females. A new diagnosis is proposed for the genus Paroecobius Lamoral, 1981 and a new record for the synanthropic Oecobius marathaus Tikader, 1962 is provided for Madagascar.


Assuntos
Aranhas , Distribuição Animal , Animais , Feminino , Madagáscar , Masculino
13.
Cladistics ; 34(6): 579-626, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34706482

RESUMO

Gnaphosidae Pocock are a very diverse spider family with remarkable spinning organ morphology. Although the family has received intense taxonomic attention in recent years, its intergeneric relationships remain obscure. A phylogenetic analysis of Gnaphosidae genera was performed to untangle the evolutionary history of the family. A matrix of 324 morphological characters, scored for 71 gnaphosid genera and 29 outgroup taxa, was analysed through parsimony and Bayesian phylogenetic inference. Gnaphosidae are not recovered as a monophyletic group, neither were most of the previously proposed intrafamiliar groupings. In accordance with the phylogenetic results obtained, Vectius Simon and Hemicloea Thorell are transferred to Trochanteriidae, and Xenoplectus Schiapelli & Gerschman de Pikelin to Liocranidae. Micaria Westring, Nauhea Forster and Verita Ramírez & Grismado (and some related genera) are probably not gnaphosids, although their phylogenetic placement is uncertain. Gnaphosidae s.s. are defined as spiders with enlarged piriform gland spigots, longer and wider than the major ampullate gland spigots. Within Gnaphosidae s.s., well-supported clades allow the redefinition, on the basis of quantitative phylogenetic evidence, of Gnaphosinae Pocock, Zelotinae Platnick, Herpyllinae Platnick, Drassodinae Simon, Prodidominae Simon rank res. and the newly proposed Leptodrassinae subfam. nov. Many genera are not assigned to subfamily given their poorly supported and unstable relationships. The homology and evolution of structures such as the claw tuft clasper, the spinning organs and the modification of cheliceral promargin are discussed.

14.
An. acad. bras. ciênc ; 89(3): 1543-1553, July-Sept. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886741

RESUMO

ABSTRACT A list of spider species is presented for the Belém Area of Endemism, the most threatened region in the Amazon Basin, comprising portions of eastern State of Pará and western State of Maranhão, Brazil. The data are based both on records from the taxonomic and biodiversity survey literature and on scientific collection databases. A total of 319 identified species were recorded, with 318 occurring in Pará and only 22 in Maranhão. About 80% of species are recorded at the vicinities of the city of Belém, indicating that sampling effort have been strongly biased. To identify potentially high-diversity areas, discounting the effect of variations in sampling effort, the residues of a linear regression between the number of records and number of species mapped in each 0.25°grid cells were analyzed. One grid, representing the Alto Turiaçu Indigenous land, had the highest deviation from the expected from the linear regression, indicating high expected species richness. Several other grid cells showed intermediate values of the regression residuals, indicating species richness moderately above to the expected from the model.


Assuntos
Animais , Aranhas/classificação , Biodiversidade , Brasil , Densidade Demográfica , Geografia
15.
Sci Rep ; 7(1): 9141, 2017 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-28831073

RESUMO

Although Brazil is a megadiverse country and thus a conservation priority, no study has yet quantified conservation gaps in the Brazilian protected areas (PAs) using extensive empirical data. Here, we evaluate the degree of biodiversity protection and knowledge within all the Brazilian PAs through a gap analysis of vertebrate, arthropod and angiosperm occurrences and phylogenetic data. Our results show that the knowledge on biodiversity in most Brazilian PAs remain scant as 71% of PAs have less than 0.01 species records per km2. Almost 55% of Brazilian species and about 40% of evolutionary lineages are not found in PAs, while most species have less than 30% of their geographic distribution within PAs. Moreover, the current PA network fails to protect the majority of endemic species. Most importantly, these results are similar for all taxonomic groups analysed here. The methods and results of our countrywide assessment are suggested to help design further inventories in order to map and secure the key biodiversity of the Brazilian PAs. In addition, our study illustrates the most common biodiversity knowledge shortfalls in the tropics.


Assuntos
Artrópodes/crescimento & desenvolvimento , Conservação dos Recursos Naturais/métodos , Magnoliopsida/crescimento & desenvolvimento , Vertebrados/crescimento & desenvolvimento , Animais , Artrópodes/classificação , Biodiversidade , Brasil , Espécies em Perigo de Extinção , Magnoliopsida/classificação , Filogenia , Vertebrados/classificação
16.
An Acad Bras Cienc ; 89(3): 1543-1553, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28832719

RESUMO

A list of spider species is presented for the Belém Area of Endemism, the most threatened region in the Amazon Basin, comprising portions of eastern State of Pará and western State of Maranhão, Brazil. The data are based both on records from the taxonomic and biodiversity survey literature and on scientific collection databases. A total of 319 identified species were recorded, with 318 occurring in Pará and only 22 in Maranhão. About 80% of species are recorded at the vicinities of the city of Belém, indicating that sampling effort have been strongly biased. To identify potentially high-diversity areas, discounting the effect of variations in sampling effort, the residues of a linear regression between the number of records and number of species mapped in each 0.25°grid cells were analyzed. One grid, representing the Alto Turiaçu Indigenous land, had the highest deviation from the expected from the linear regression, indicating high expected species richness. Several other grid cells showed intermediate values of the regression residuals, indicating species richness moderately above to the expected from the model.


Assuntos
Biodiversidade , Aranhas/classificação , Animais , Brasil , Geografia , Densidade Demográfica
17.
Sci Rep ; 7(1): 2992, 2017 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-28592879

RESUMO

Amazonian rivers are usually suggested as dispersal barriers, limiting biogeographic units. This is evident in a widely accepted Areas of Endemism (AoEs) hypothesis proposed for Amazonian birds. We empirically test this hypothesis based on quantitative analyses of species distribution. We compiled a database of bird species and subspecies distribution records, and used this dataset to identify AoEs through three different methods. Our results show that the currently accepted Amazonian AoEs are not consistent with areas identified, which were generally congruent among datasets and methods. Some Amazonian rivers represent limits of AoEs, but these areas are not congruent with those previously proposed. However, spatial variation in species composition is correlated with largest Amazonian rivers. Overall, the previously proposed Amazonian AoEs are not consistent with the evidence from bird distribution. However, the fact that major rivers coincide with breaks in species composition suggest they can act as dispersal barriers, though not necessarily for all bird taxa. This scenario indicates a more complex picture of the Amazonian bird distribution than previously imagined.


Assuntos
Distribuição Animal , Aves/crescimento & desenvolvimento , Filogeografia , Animais , Rios
18.
Zootaxa ; 4216(5): zootaxa.4216.5.3, 2017 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-28183107

RESUMO

The spider genus Oxyopes Latreille occurs throughout the world, but is insufficiently known in South America and the Caribbean. In this study, three apparently related species of this genus are reported from the region. Oxyopes salticus Hentz, 1845 is redescribed and illustrated, and extreme variation in colour pattern and in female genitalia is reported within this species. Oxyopes m-fasciatus Piza, 1938 and Oxyopes nigrolineatus Mello-Leitão, 1941 are both considered junior synonyms of O. salticus. The material examined in this study, together with information from the literature, show this species is widely distributed throughout the continental Americas and the Caribbean. Oxyopes crewi Bryant, 1948 is redescribed and illustrated, and its geographic distribution is extended to Bahamas, Cuba, Dominican Republic, Jamaica, and Saint Kitts. A new species, Oxyopes incantatus sp. nov., is described and illustrated for the first time based on specimens from the Galápagos Islands.


Assuntos
Aranhas/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Ecossistema , Feminino , Masculino , Tamanho do Órgão , América do Sul , Aranhas/anatomia & histologia , Aranhas/crescimento & desenvolvimento
19.
Eur. J. Taxon. ; 388: 1-20, 2017.
Artigo em Inglês | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib17813

RESUMO

Loxosceles Heineken & Lowe, 1832 spiders are infamous for their medical importance, but a taxonomic picture of the genus is still far from complete. In this study, the Chilean species of Loxosceles are described and mapped. The males of Loxosceles surca Gertsch, 1967 and L. coquimbo Gertsch, 1967 are described for the first time. Three new species with narrow distributions are described from central and northern Chile: Loxosceles diaguita sp. nov. from the Antofagasta Region, L. pallalla sp. nov. from Coquimbo and L. vallenar sp. nov. from Atacama. The first two species are remarkable in their morphology and do not fit into any of Gertsch’s species groups, suggesting that Chile still harbours an undiscovered phylogenetic diversity of the genus. New distribution records for Loxosceles laeta (Nicolet, 1849) are provided throughout Chile.

20.
Iheringia Ser. Zool. ; 107(Supl.): e2017109, 2017.
Artigo em Português | Sec. Est. Saúde SP, SESSP-IBPROD, Sec. Est. Saúde SP | ID: but-ib15521

RESUMO

Nós compilamos uma lista de espécies de aranhas registradas no Mato Grosso do Sul (Brasil) a partir da literatura taxonômica e de inventários não publicados. A lista inclui 228 espécies em 134 gêneros e 32 famílias. Apenas cerca de 35% da área do estado apresenta registros de ocorrência de espécies de aranhas, e não mais que 5% apresenta mais de um registro de ocorrência por quadrícula de 0,5° (˜2.916 km2). Existem grandes lacunas de amostragem no estado, particularmente na porção norte do Pantanal. A maioria das espécies tem menos de 10 registros de ocorrência, ou seja, sua distribuição geográfica é praticamente desconhecida. Extrapolando a curva de acumulação de espécies dessas aranhas, concluímos que seria necessário ampliar em 10 vezes a área amostrada para que sejam listadas 90% das espécies que ocorrem no estado. Número de espécies: no mundo, 44.906; no Brasil, 3.730; no Mato Grosso do Sul, 228. Portanto, novos inventários são essenciais para que a araneofauna do Mato Grosso do Sul seja minimamente conhecida.


Here we compile a list of spider species recorded in Mato Grosso do Sul state (Brazil), based on information from the taxonomic literature and unpublished inventories. The list includes 228 species in 134 genera and 32 families. Only approximately 35% of the state area have records of spider species, and no more than 5% of the area presents more than one record per 0.5° grid cell (˜2,916 km2). There are large gaps in the knowledge of the state’s spider fauna, particularly in the northern Pantanal. Most of the species are known by less than 10 distribution records, indicating that their geographic distribution is virtually unknown. Extrapolating a species accumulation curve, we show that a ten-time increase in sampled area would be necessary to discover 90% of the species occurring in the state. Number of species: in the world, 44,906; in Brazil, 3,730; in Mato Grosso do Sul, 228. Therefore new inventories are essential for an adequate description of the spider fauna of the state of Mato Grosso do Sul.

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