Insights into the karyotype evolution and speciation of the beetle Euchroma gigantea (Coleoptera: Buprestidae)

Autor(es)

Xavier, Crislaine ^[1] ; Santos Soares, Rogean Vinicius ^[1] ; Amorim, Igor Costa ^[1] ; Cabral-de-Mello, Diogo Cavalcanti ^[2] ; de Moura, Rita de Cassia ^[1]

Afiliação do(s) autor(es)

^[1] Univ Pernambuco UPE, Inst Ciencias Biol, Lab Biodiversidade & Genet Insetos, Rua Arnobio Marques 310, BR-50100130 Recife, PE - Brazil

^[2] Univ Estadual Paulista UNESP, Dept Biol, Inst Biociencias, Rio Claro, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Chromosome Research; v. 26, n. 3, p. 163-178, SEP 2018.
• Citações Web of Science: 1

Resumo

Euchroma Dejean, 1833 (Buprestidae: Coleoptera) is a monotypic genus comprising the species Euchroma gigantea, with populations presenting a degree of karyotypic variation/polymorphism rarely found within a single taxonomic (specific) unit, as well as drastically incompatible meiotic configurations in populations from extremes of the species range. To better understand the complex karyotypic evolution of E. gigantea, the karyotypes of specimens from five populations in Brazil were investigated using molecular cytogenetics and phylogenetic approaches. Herein, we used FISH with histone genes as well as sequencing of the COI to determine differential distribution of markers and relationships among populations. The analyses revealed new karyotypes, with variability for chromosome number and morphology of multiple sex chromosome mechanisms, occurrence of B chromosome variants (punctiform and large ones), and high dispersion of histone genes in different karyotypes. These data indicate that chromosomal polymorphism in E. gigantea is greater than previously reported, and that the species can be a valuable model for cytogenetic studies. The COI phylogenetic and haplotype analyses highlighted the formation of three groups with chromosomally polymorphic individuals. Finally, we compared the different karyotypes and proposed a model for the chromosomal evolution of this species. The species E. gigantea includes at least three cytogenetically polymorphic lineages. Moreover, in each of these lineages, different chromosomal rearrangements have been fixed. Dispersion of repetitive sequences may have favored the high frequency of these rearrangements, which could be related to both adaptation of the species to different habitats and the speciation process. (AU)

• Processo FAPESP: 14/11763-8 - Contribuições ao entendimento da estrutura e evolução de sistemas de cromossomos sexuais utilizando como modelos espécies de gafanhotos e grilos
• Beneficiário: Diogo Cavalcanti Cabral de Mello
• Modalidade de apoio: Auxílio à Pesquisa - Regular