Molecular Phylogenetics of Dichoplus and related genera: karyotype diversification.

COLOMBO, P., CIGLIANO, M, SEQUEIRA, A., LANGE, C., VILARDI, J., CONFALONIERI, V.A.

CLADISTICS (PRINT)

Ed. Blackwell Publishing and The Willi Hennig Society

Año: 2005 vol. 21 p. 375 - 381

0748-3007

The neotropical genus Dichroplus and related genera are characterized by a relatively uniform external morphology and a remarkably divergent male genitalia and hence its taxonomy is controversial. It also shows an extreme karyotypic diversi.cation. In this study we used molecular and morphological characters to test the monophyly of the genus and to evaluate chromosome evolution. Twenty-seven species from Dichroplus and related genera were included in the analysis. Morphological characters refer to the general morphology, male genitalia and female structures. Molecular studies were performed, sequencing part of two mitochondrial genes, cytochrome oxidase I and II. Independent and combined phylogenetic analyses of the data were performed under maximum parsimony. The karyotypic characters (rearrangements) were either mapped onto the combined topology or combined with the other data sets. While the molecular analysis con.rms some results attained with morphology, some others do not. All point towards the paraphyly of the genus. Our results show the relevance of morphological data in phylogenetic studies because morphology and molecules supply complementary evidence. The mapping of chromosome characters on the combined tree shows that the most extreme karyotype, in D. silveiraguidoi, is a derived condition, probably reached through several centric fusions, and that X-autosome centric fusions were recurrently .xed during the evolution of the group.Dichroplus and related genera are characterized by a relatively uniform external morphology and a remarkably divergent male genitalia and hence its taxonomy is controversial. It also shows an extreme karyotypic diversi.cation. In this study we used molecular and morphological characters to test the monophyly of the genus and to evaluate chromosome evolution. Twenty-seven species from Dichroplus and related genera were included in the analysis. Morphological characters refer to the general morphology, male genitalia and female structures. Molecular studies were performed, sequencing part of two mitochondrial genes, cytochrome oxidase I and II. Independent and combined phylogenetic analyses of the data were performed under maximum parsimony. The karyotypic characters (rearrangements) were either mapped onto the combined topology or combined with the other data sets. While the molecular analysis con.rms some results attained with morphology, some others do not. All point towards the paraphyly of the genus. Our results show the relevance of morphological data in phylogenetic studies because morphology and molecules supply complementary evidence. The mapping of chromosome characters on the combined tree shows that the most extreme karyotype, in D. silveiraguidoi, is a derived condition, probably reached through several centric fusions, and that X-autosome centric fusions were recurrently .xed during the evolution of the group.Dichroplus and related genera were included in the analysis. Morphological characters refer to the general morphology, male genitalia and female structures. Molecular studies were performed, sequencing part of two mitochondrial genes, cytochrome oxidase I and II. Independent and combined phylogenetic analyses of the data were performed under maximum parsimony. The karyotypic characters (rearrangements) were either mapped onto the combined topology or combined with the other data sets. While the molecular analysis con.rms some results attained with morphology, some others do not. All point towards the paraphyly of the genus. Our results show the relevance of morphological data in phylogenetic studies because morphology and molecules supply complementary evidence. The mapping of chromosome characters on the combined tree shows that the most extreme karyotype, in D. silveiraguidoi, is a derived condition, probably reached through several centric fusions, and that X-autosome centric fusions were recurrently .xed during the evolution of the group.D. silveiraguidoi, is a derived condition, probably reached through several centric fusions, and that X-autosome centric fusions were recurrently .xed during the evolution of the group. The Willi Hennig Society 2005.The Willi Hennig Society 2005.