Relações filogenéticas do grupo panarthropoda avaliadas através de sequências do gene rDNA 18s

Abstract

The group Ecdysozoa is compounded by invertebrates that make cuticle exchange or ecdise. This group was proposed by Aguinaldo et al.1997 in his molecular analysis with the 18S ribosomal subunit and it contrasts with the morphological hypothesis of the Articulata group. In the Ecdysozoa, there is a group of animals with similar characteristics called Panarthropoda. This group is compounded by Onychophora, Tardigrada and Euarhtropoda. It has been discussed a lot about basal group ofPanarthropoda and also about the phylogenetic relationships among members of this group. The 18S is a molecular orthologue marker gene and it has been used in many studies of phylogeny with good acceptance for the resolution of the relationships between clades. This study aimed to solve the phylogenetic position of the phylum Onychophora within the group using Panarthropoda as sequence markers of the 18S gene. For this analysis it was used the methods of maximum parsimony, maximumlikelihood and Bayesian analysis. Although it has been found statistical support for the relationship between some groups of Panarthropoda, there was no sufficient statistical support to solve the position of the phylum Onychophora.