Phylogenetic analysis and systematic revision of the genus Anchylohynchus Schoenherr, 1836 (Curculionidae: Derelomini), using discrete and continuous morphological characters

Author(s)

Bruno Augusto Souza de Medeiros

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
• Defense date: 2011-07-07

Examining board members

Sergio Antonio Vanin; José Ricardo Miras Mermudes; Silvio Shigueo Nihei

• Advisor: Sergio Antonio Vanin

Abstract

Recently, phylogenetic analysis based on continuous characters was made accessible. This increases the pool of characters available for morphology-based phylogenetic analyses, but there is still no consensus on how this kind of characters should be coded and analyzed. In the present study, I assessed the use of continuous characters in phylogenies from two distinct perspectives: computer simulations and an application to real data. The simulations indicate that one can indeed recover phylogenies based on continuous characters, given some precautions. The most important of them is the use of implied weighting. Even when this is done, poorly supported branches may be incorrect, probably due to long-branch attraction. For the phylogenetic analysis of Anchylorhynchus, I used both continuous and discrete characters, separately or combined. Trees obtained with separate matrices were significantly different, and the combined matrix resulted in a tree very similar to the tree obtained with discrete characters alone. Branch supports, however, increased with the addition of continuous characters. Continuous characters, therefore, should not be considered an alternative to traditional analyses. Rather, they should be added to discrete-character matrices. The taxonomic revision of Anchylorhynchus resulted in nine new species described and four new synonyms recognized. The genus resulted to be a monophyletic group containing 24 recognized species. Moreover, the information on weevils\' biology and geographical distribution was updated. Together with the phylogeny this information embased reconstructions of host relationships and biogeography. (AU)