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Antonio D Brescovit - One of the best experts on this subject based on the ideXlab platform.

  • insights on repetitive dna behavior in two species of ctenus walckenaer 1805 and guasuctenus polotow and brescovit 2019 araneae Ctenidae evolutionary profile of h3 histone 18s rrna genes and heterochromatin distribution
    PLOS ONE, 2020
    Co-Authors: Matheus Pires Rincão, Antonio D Brescovit, Ana Lúcia Dias
    Abstract:

    Ctenidae represents one of the most representative spider families in the tropical forests of Brazil. Its largest genus, Ctenus, has approximately 220 species out of the more than 520 Ctenidae species described, and several authors consider it polyphyletic. Chromosomal data are only available for four species of Ctenus, representing a large gap in the cytogenetic knowledge about the group. This study provided cytogenetic data on two Ctenus species and one Guasuctenus (previously described as Ctenus). All showed 2n♂ = 28 (26+X1X20). Guasuctenus longipes presented two chromosome pairs containing 18S rDNA genes and C. medius, however C. ornatus showed only one chromosome pair with the 18S rDNA gene. Hybridization data using histone H3 probe indicated specific profiles: histone H3 genes were found in one chromosome pair in G. longipes, in three pairs in C. medius, and in four pairs in C. ornatus. Furthermore, supernumerary chromosomes were identified in C. ornatus presenting a meiotic behavior similar to that of sex chromosomes; and a trivalent was found in C. medius, formed by the association of one sex chromosome and an autosomal bivalent, indicating the importance of these events for the diversification of sex chromosomes in spiders. The C-banding pattern was similar between C. medius and C. ornatus with regard to the number and locations of heterochromatic bands, suggesting that heterochromatin amplification and dispersion, affect karyotypic evolution in the genus. Cytogenetic data showed similarity between C. medius and C. ornatus, and differentiation of G. longipes congruent with morphological data. Moreover, although more comparative analyses are needed to specify composition of the dispersed heterochromatin in Ctenus, the mapping of heterochromatic bands provided insights about the evolution of the karyotypes in this genus.

  • phylogenetic analysis of the tropical wolf spider subfamily cteninae arachnida araneae Ctenidae
    Zoological Journal of the Linnean Society, 2014
    Co-Authors: Daniele Polotow, Antonio D Brescovit
    Abstract:

    A cladistic analysis based on parsimony was performed to test the monophyly of Cteninae. The data matrix comprises 72 terminal taxa scored for 88 characters from external morphology, female internal genitalia, and two behavioural characters. Cteninae, as currently delimited, is polyphyletic. The monoplyly of Cteninae requires the transfer of two Ctenus species to Enoploctenus (Acantheinae) and two Ctenus species to Asthenoctenus (Viridasiinae). Ctenus, the genus type, comprises approximately half of the described species of the family, and is polyphyletic as currently delimited. From the 32 Ctenus species added to this analysis, only 13 are recognized as Ctenus s.s.: (C. rectipes (C. pauloterrai (C. manauara, C. nigritus ((C. dubius, C. crulsi) ((C. amphora, C. minor) (C. medius, C. paubrasil (C. fernandae (C. ornatus, C. vehemens)))))))). The results suggest that at least eight new genera should be described to accommodate species misplaced in Ctenus. The result also refutes the monophyly of Amauropelma Raven, Stumkat & Gray, 2001, Celaetycheus Simon, 1897, Leptoctenus L. Koch, 1878, and Thoriosa Simon, 1910. The following taxonomic changes are proposed: Ctenus inazensis Strand, 1909 and Ctenus miserabilis Strand, 1916 are transferred to Enoploctenus; Ctenus tarsalis F.O. Pickard-Cambridge, 1902 and Ctenus bulimus Strand, 1909 are transferred to Asthenoctenus Simon, 1897; Celaetycheus modestus Bryant, 1942 is transferred to Ohvida Polotow & Brescovit, 2009. © 2014 The Linnean Society of London

  • microhabitat selection and co occurrence of pachistopelma rufonigrum pocock araneae theraphosidae and nothroctenus fuxico sp nov araneae Ctenidae in tank bromeliads from serra de itabaiana sergipe brazil
    Revista Brasileira De Zoologia, 2004
    Co-Authors: Sidclay Calaca Dias, Antonio D Brescovit
    Abstract:

    Microhabitat selection and co-occurrence of Pachistopelma rufonigrum Pocock (Theraphosidae) and Nothroctenus fuxico sp. nov. (Ctenidae), in tank bromeliads were investigated. Thermal conditions, inside and outside the plants, were measured in order to verify if the temperature of the water that accumulates inside the plant affects the behavior of these species. Measurements of foliar parameters were taken in order to evaluate if and how plant structure affects spider abundance and microhabitat selection. Apparently, differences in plant structure do not affect either spider abundance or microhabitat selection. No microhabitat preference was observed and co-ocurrence of both species was a random event. In addition, notes on the distribution range of P. rufonigrum and the description of N. fuxico sp. nov. from State of Sergipe, Brazil are presented.

  • Microhabitat selection and co-occurrence of Pachistopelma rufonigrum Pocock (Araneae, Theraphosidae) and Nothroctenus fuxico sp. nov. (Araneae, Ctenidae) in tank bromeliads from Serra de Itabaiana, Sergipe, Brazil
    Sociedade Brasileira de Zoologia, 2004
    Co-Authors: Sidclay Calaca Dias, Antonio D Brescovit
    Abstract:

    Microhabitat selection and co-occurrence of Pachistopelma rufonigrum Pocock (Theraphosidae) and Nothroctenus fuxico sp. nov. (Ctenidae), in tank bromeliads were investigated. Thermal conditions, inside and outside the plants, were measured in order to verify if the temperature of the water that accumulates inside the plant affects the behavior of these species. Measurements of foliar parameters were taken in order to evaluate if and how plant structure affects spider abundance and microhabitat selection. Apparently, differences in plant structure do not affect either spider abundance or microhabitat selection. No microhabitat preference was observed and co-ocurrence of both species was a random event. In addition, notes on the distribution range of P. rufonigrum and the description of N. fuxico sp. nov. from State of Sergipe, Brazil are presented.Foram estudadas a seleção de microhabitat e co-ocorrência de Pachistopelma rufonigrum Pocock (Theraphosidae) e Nothroctenus fuxico sp. nov. (Ctenidae) em bromélias-tanque. A condição da temperatura dentro e fora das plantas foi medida para verificar se a temperatura da água acumulada dentro da bromélia afeta algum aspecto comportamental das aranhas que ali vivem. Medidas dos parâmetros foliares foram realizadas para avaliar se a estrutura das plantas chega a afetar a abundância ou a seleção de microhabitat dessas aranhas. Aparentemente, as diferenças na estrutura das duas espécies de bromélias estudadas não afetam nem a abundância, nem a seleção de microhabitat de P. rufonigrum e N. fuxico sp. nov. A preferência e co-ocorrência de ambas as espécies de aranhas parece ser um evento ao acaso. Adicionalmente, apresenta-se notas sobre os limites de distribuição de P. rufonigrum e descreve-se N. fuxico sp. nov. do Estado de Sergipe, Brasil

Silva-dávila Diana. - One of the best experts on this subject based on the ideXlab platform.

  • Revision of the spider genus Caloctenus Keyserling, 1877 (Araneae, Ctenidae
    Facultad de Ciencias Biológicas Universidad Nacional Mayor de San Marcos, 2013
    Co-Authors: Silva-dávila Diana.
    Abstract:

    Se examina y redefine el género Caloctenus Keyserling. Este grupo incluye arañas pequeñas que se caracterizan por tener el cefalotórax con las regiones cefálica y torácica bien delimitadas por surcos profundos; el cuerpo enteramente cubierto por escamas iridicentes y una combinación de 5- 8/6-7 pares de espinas ventrales en las tibias/metatarsos del primer y segundo par de patas. Caloctenus incluye cuatro especies del norte de Sudamérica, se proporciona una clave para identificarlas. Los ejemplares machos de C. aculeatus Keys. y C. gracilitarsis Simon se describen por primera vez. Se presenta dos nuevas especies: C. carbonera, de Venezuela y C. oxapampa, del Perú. Otras especies previamente descritas bajo este género pertenecen a otros grupos. Caloctenus boetonensis Strand, C. celer Simon, y C. oreus Simon se transfieren al género Acantheis Thorell, 1891. Caloctenus fernandensis Simon se transfiere a Africactenus Hyatt, 1954. Caloctenus penicilliger Simon y C. variegatus Bertkau se transfieren a Enoploctenus Simon, 1897. Caloctenus abyssinicus Strand se considera incertae sedis en Ctenidae.Caloctenus Keyserling is examined and redefined to include small ground-dwelling spiders with an enhanced ventral spination beneath anterior tibiae/metatarsi -a combination of five-eight/six-seven paired-spines, pars cephalica well marked by a deep furrow, strongly convex pars thoracica, and body thickly coated with iridescent scales. As relimited, Caloctenus comprises four species from northern South America; a key to identify them is provided. Males of C. aculeatus Keyserling and C. gracilitarsis Simon are described for the first time, as are two new species, C. carbonera from Venezuela, and C. oxapampa from Peru. All other species described under this genus belong somewhere else. Caloctenus boetonensis Strand, C. celer Simon, and C. oreus Simon are transferred to Acantheis Thorell, 1891. Caloctenus fernandensis Simon is transferred to Africactenus Hyatt, 1954. Caloctenus penicilliger Simon and C. variegatus Bertkau are transferred to Enoploctenus Simon,1897. Caloctenus abyssinicus Strand is placed incertae sedis within Ctenidae

  • Revisión del género de arañas Caloctenus Keyserling, 1877 (Araneae, Ctenidae)
    Revista Peruana de Biología, 2011
    Co-Authors: Silva-dávila Diana.
    Abstract:

    SILVA-DAVILA, Diana. Revisión del género de arañas Caloctenus Keyserling, 1877 (Araneae, Ctenidae). Revista Peruana de Biología [en línea] ene./jul. 2004, vol. 11, no. 1, p.5-26. ISSN 1727-9933.Se examina y redefine el género Caloctenus Keyserling. Este grupo incluye arañas pequeñas que se caracterizan por tener el cefalotórax con las regiones cefálica y torácica bien delimitadas por surcos profundos; el cuerpo enteramente cubierto por escamas iridicentes y una combinación de 5-8/6-7 pares de espinas ventrales en las tibias/metatarsos del primer y segundo par de patas. Caloctenus incluye cuatro especies del norte de Sudamérica, se proporciona una clave para identificarlas. Los ejemplares machos de C. aculeatus Keys. y C. gracilitarsis Simon se describen por primera vez. Se presenta dos nuevas especies: C. carbonera, de Venezuela y C. oxapampa, del Perú. Otras especies previamente descritas bajo este género pertenecen a otros grupos. Caloctenus boetonensis Strand, C. celer Simon, y C. oreus Simon se transfieren al género Acantheis Thorell, 1891. Caloctenus fernandensis Simon se transfiere a Africactenus Hyatt, 1954. Caloctenus penicilliger Simon y C. variegatus Bertkau se transfieren a Enoploctenus Simon, 1897. Caloctenus abyssinicus Strand se considera incertae sedis en Ctenidae

  • Revisión del género de arañas Caloctenus Keyserling, 1877 (Araneae, Ctenidae)
    'Universidad Nacional Mayor de San Marcos Vicerectorado de Investigacion', 2004
    Co-Authors: Silva-dávila Diana.
    Abstract:

    Caloctenus Keyserling is examined and redefined to include small ground-dwelling spiders with an enhanced ventral spination beneath anterior tibiae/metatarsi -a combination of five-eight/six-seven paired-spines, pars cephalica well marked by a deep furrow, strongly convex pars thoracica, and body thickly coated with iridescent scales. As relimited, Caloctenus comprises four species from northern South America; a key to identify them is provided. Males of C. aculeatus Keyserling and C. gracilitarsis Simon are described for the first time, as are two new species, C. carbonera from Venezuela, and C. oxapampa from Peru. All other species described under this genus belong somewhere else. Caloctenus boetonensis Strand, C. celer Simon, and C. oreus Simon are transferred to Acantheis Thorell, 1891. Caloctenus fernandensis Simon is transferred to Africactenus Hyatt, 1954. Caloctenus penicilliger Simon and C. variegatus Bertkau are transferred to Enoploctenus Simon,1897. Caloctenus abyssinicus Strand is placed incertae sedis within Ctenidae.Se examina y redefine el género Caloctenus Keyserling. Este grupo incluye arañas pequeñas que se caracterizan por tener el cefalotórax con las regiones cefálica y torácica bien delimitadas por surcos profundos; el cuerpo enteramente cubierto por escamas iridicentes y una combinación de 5- 8/6-7 pares de espinas ventrales en las tibias/metatarsos del primer y segundo par de patas. Caloctenus incluye cuatro especies del norte de Sudamérica, se proporciona una clave para identificarlas. Los ejemplares machos de C. aculeatus Keys. y C. gracilitarsis Simon se describen por primera vez. Se presenta dos nuevas especies: C. carbonera, de Venezuela y C. oxapampa, del Perú. Otras especies previamente descritas bajo este género pertenecen a otros grupos. Caloctenus boetonensis Strand, C. celer Simon, y C. oreus Simon se transfieren al género Acantheis Thorell, 1891. Caloctenus fernandensis Simon se transfiere a Africactenus Hyatt, 1954. Caloctenus penicilliger Simon y C. variegatus Bertkau se transfieren a Enoploctenus Simon, 1897. Caloctenus abyssinicus Strand se considera incertae sedis en Ctenidae

Daniele Polotow - One of the best experts on this subject based on the ideXlab platform.

  • total evidence analysis of the phylogenetic relationships of lycosoidea spiders araneae entelegynae
    Invertebrate Systematics, 2015
    Co-Authors: Charles E Griswold, Daniele Polotow, Anthea Carmichael
    Abstract:

    Phylogenetic relationships within the superfamily Lycosoidea are investigated through the coding and analysis of character data derived from morphology, behaviour and DNA sequences. In total, 61 terminal taxa were studied, representing most of the major groups of the RTA-clade (i.e. spiders that have a retrolateral tibial apophysis on the male palp). Parsimony and model-based approaches were used, and several support values, partitions and implied weighting schemes were explored to assess clade stability. The morphological–behavioural matrix comprised 96 characters, and four gene fragments were used: 28S (~737 base pairs), actin (~371 base pairs), COI (~630 base pairs) and H3 (~354 base pairs). Major conclusions of the phylogenetic analysis include: the concept of Lycosoidea is restricted to seven families: Lycosidae, Pisauridae, Ctenidae, Psechridae, Thomisidae, Oxyopidae (but Ctenidae and Pisauridae are not monophyletic) and also Trechaleidae (not included in the analysis); the monophyly of the ‘Oval Calamistrum clade’ (OC-clade) appears to be unequivocal, with high support, and encompassing the Lycosoidea plus the relimited Zoropsidae and the proposed new family Udubidae (fam. nov.); Zoropsidae is considered as senior synonym of Tengellidae and Zorocratidae (syn. nov.); Viridasiinae (rank nov.) is raised from subfamily to family rank, excluded from the Ctenidae and placed in Dionycha. Our quantitative phylogenetic analysis confirms the synonymy of Halidae with Pisauridae. The grate-shaped tapetum appears independently at least three times and has a complex evolutionary history, with several reversions.

  • phylogenetic analysis of the tropical wolf spider subfamily cteninae arachnida araneae Ctenidae
    Zoological Journal of the Linnean Society, 2014
    Co-Authors: Daniele Polotow, Antonio D Brescovit
    Abstract:

    A cladistic analysis based on parsimony was performed to test the monophyly of Cteninae. The data matrix comprises 72 terminal taxa scored for 88 characters from external morphology, female internal genitalia, and two behavioural characters. Cteninae, as currently delimited, is polyphyletic. The monoplyly of Cteninae requires the transfer of two Ctenus species to Enoploctenus (Acantheinae) and two Ctenus species to Asthenoctenus (Viridasiinae). Ctenus, the genus type, comprises approximately half of the described species of the family, and is polyphyletic as currently delimited. From the 32 Ctenus species added to this analysis, only 13 are recognized as Ctenus s.s.: (C. rectipes (C. pauloterrai (C. manauara, C. nigritus ((C. dubius, C. crulsi) ((C. amphora, C. minor) (C. medius, C. paubrasil (C. fernandae (C. ornatus, C. vehemens)))))))). The results suggest that at least eight new genera should be described to accommodate species misplaced in Ctenus. The result also refutes the monophyly of Amauropelma Raven, Stumkat & Gray, 2001, Celaetycheus Simon, 1897, Leptoctenus L. Koch, 1878, and Thoriosa Simon, 1910. The following taxonomic changes are proposed: Ctenus inazensis Strand, 1909 and Ctenus miserabilis Strand, 1916 are transferred to Enoploctenus; Ctenus tarsalis F.O. Pickard-Cambridge, 1902 and Ctenus bulimus Strand, 1909 are transferred to Asthenoctenus Simon, 1897; Celaetycheus modestus Bryant, 1942 is transferred to Ohvida Polotow & Brescovit, 2009. © 2014 The Linnean Society of London

Polotow Daniele - One of the best experts on this subject based on the ideXlab platform.

Sidclay Calaca Dias - One of the best experts on this subject based on the ideXlab platform.

  • microhabitat selection and co occurrence of pachistopelma rufonigrum pocock araneae theraphosidae and nothroctenus fuxico sp nov araneae Ctenidae in tank bromeliads from serra de itabaiana sergipe brazil
    Revista Brasileira De Zoologia, 2004
    Co-Authors: Sidclay Calaca Dias, Antonio D Brescovit
    Abstract:

    Microhabitat selection and co-occurrence of Pachistopelma rufonigrum Pocock (Theraphosidae) and Nothroctenus fuxico sp. nov. (Ctenidae), in tank bromeliads were investigated. Thermal conditions, inside and outside the plants, were measured in order to verify if the temperature of the water that accumulates inside the plant affects the behavior of these species. Measurements of foliar parameters were taken in order to evaluate if and how plant structure affects spider abundance and microhabitat selection. Apparently, differences in plant structure do not affect either spider abundance or microhabitat selection. No microhabitat preference was observed and co-ocurrence of both species was a random event. In addition, notes on the distribution range of P. rufonigrum and the description of N. fuxico sp. nov. from State of Sergipe, Brazil are presented.

  • Microhabitat selection and co-occurrence of Pachistopelma rufonigrum Pocock (Araneae, Theraphosidae) and Nothroctenus fuxico sp. nov. (Araneae, Ctenidae) in tank bromeliads from Serra de Itabaiana, Sergipe, Brazil
    Sociedade Brasileira de Zoologia, 2004
    Co-Authors: Sidclay Calaca Dias, Antonio D Brescovit
    Abstract:

    Microhabitat selection and co-occurrence of Pachistopelma rufonigrum Pocock (Theraphosidae) and Nothroctenus fuxico sp. nov. (Ctenidae), in tank bromeliads were investigated. Thermal conditions, inside and outside the plants, were measured in order to verify if the temperature of the water that accumulates inside the plant affects the behavior of these species. Measurements of foliar parameters were taken in order to evaluate if and how plant structure affects spider abundance and microhabitat selection. Apparently, differences in plant structure do not affect either spider abundance or microhabitat selection. No microhabitat preference was observed and co-ocurrence of both species was a random event. In addition, notes on the distribution range of P. rufonigrum and the description of N. fuxico sp. nov. from State of Sergipe, Brazil are presented.Foram estudadas a seleção de microhabitat e co-ocorrência de Pachistopelma rufonigrum Pocock (Theraphosidae) e Nothroctenus fuxico sp. nov. (Ctenidae) em bromélias-tanque. A condição da temperatura dentro e fora das plantas foi medida para verificar se a temperatura da água acumulada dentro da bromélia afeta algum aspecto comportamental das aranhas que ali vivem. Medidas dos parâmetros foliares foram realizadas para avaliar se a estrutura das plantas chega a afetar a abundância ou a seleção de microhabitat dessas aranhas. Aparentemente, as diferenças na estrutura das duas espécies de bromélias estudadas não afetam nem a abundância, nem a seleção de microhabitat de P. rufonigrum e N. fuxico sp. nov. A preferência e co-ocorrência de ambas as espécies de aranhas parece ser um evento ao acaso. Adicionalmente, apresenta-se notas sobre os limites de distribuição de P. rufonigrum e descreve-se N. fuxico sp. nov. do Estado de Sergipe, Brasil