Chromosomes of Theridiidae spiders (Entelegynae): interspecific karyotype diversity in Argyrodes and diploid number intraspecific variability in Nesticodes rufipes

Theridiidae is a derived family within the Araneoidea clade. In contrast to closely related groups, the 2n(male) = 20+X1X2 with acro/telocentric chromosomes is the most widespread karyotype among the theridiid spiders. In this work, the cytogenetic analysis of Argyrodes elevatus revealed original ch...

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Detalhes bibliográficos
Autores: Stavale, Leila Miguel [UNESP], Schneider, Marielle Cristina, Araujo, Douglas, Brescovit, Antonio Domingos, Cella, Doralice Maria [UNESP]
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2010
País:Brasil
Recursos:Universidade Estadual Paulista (UNESP)
Repositório:Repositório Institucional da UNESP
Idioma:inglês
OAI Identifier:oai:repositorio.unesp.br:11449/19633
Acesso em linha:http://dx.doi.org/10.1590/S1415-47572010005000076
http://hdl.handle.net/11449/19633
Access Level:Acceso aberto
Palavra-chave:chromosome morphology
cytogenetic
meiosis
nucleolar organizer region
sex chromosome system
Descrição
Resumo:Theridiidae is a derived family within the Araneoidea clade. In contrast to closely related groups, the 2n(male) = 20+X1X2 with acro/telocentric chromosomes is the most widespread karyotype among the theridiid spiders. In this work, the cytogenetic analysis of Argyrodes elevatus revealed original chromosome features different from those previously registered for Theridiidae, including the presence of 2n(male) = 20+X with meta/submetacentric chromosomes. Most individuals of Nesticodes rufipes showed family conserved karyotype characteristics. However, one individual had a 2n(male) = 24 due to the presence of an extra chromosome pair, which exhibited regular behavior and reductional segregation during meiosis. After silver staining, mitotic cells exhibited NORs localized on the terminal regions of the short arms of pairs 2, 3, and 4 of A. elevatus and on the terminal regions of long arms of pair 4 of N. rufipes. The comparative analysis with data from phylogenetically related species allowed the clarification of the origin of the interspecific and intraspecific chromosome variability observed in Argyrodes and in N. rufipes, respectively.