Molecular systematics of sclerosomatid harvestmen (Opiliones, Phalangioidea, Sclerosomatidae): Geography is better than taxonomy in predicting phylogeny

• Published in: Molecular phylogenetics and evolution 2012-01, Vol.62 (1), p.224-236
• Main Authors: Hedin, Marshal, Tsurusaki, Nobuo, Macías-Ordóñez, Rogelio, Shultz, Jeffrey W.
• Format: Article
• Language: English
• Subjects: Animals; Arachnida; Arachnida - anatomy & histology; Arachnida - classification; Arachnida - genetics; Arthropod Proteins - genetics; Bayes Theorem; Biogeography; Boreotropic Concept; Convergence; Diagnostic systems; Electron Transport Complex IV - genetics; Elongation; Evolution; Female; Genes; Genes, Mitochondrial; Geography; Histones; Histones - genetics; Likelihood Functions; Male; molecular systematics; monophyly; Morphological homoplasy; Opiliones; Peptide Elongation Factor 1 - genetics; Phalangiidae; Phylogenetics; Phylogeny; Phylogeography; polyphyly; prediction; ribosomal RNA; RNA, Ribosomal - genetics; Sequence Analysis, DNA; Tropics
• ISSN: 1055-7903; 1095-9513
• DOI: 10.1016/j.ympev.2011.09.017

[Display omitted] ► Molecular phylogenies are reconstructed for sclerosomatid harvestmen (Opiliones). ► Phylogenetic results indicate that most major scerlosomatid groups are polyphyletic. ► Molecular clades typically correspond to biogeographically regionalized faunas. ► Morphological homoplasy is evident in both somatic and reproductive morphology. Phylogenetic relationships within the Sclerosomatidae, the largest family of harvestmen, are explored using molecular data from four nuclear genes (28S and 18S rRNA, Histone 3 and Elongation factor-1α) and two mitochondrial gene regions (COI-COII, 16S and 12S rRNA). The taxon sample includes representative species from all families in Phalangioidea and all subfamilies of Sclerosomatidae (Gagrellinae, Gyinae, Leiobuninae, Sclerosomatinae). Our results solve several major taxonomic problems, including placement of Gyinae sensu stricto in Phalangiidae, the monophyly of the Metopilio group and its exclusion from Sclerosomatidae, and reaffirmation of the familial rank of Protolophidae. However, most major groups of sclerosomatids (Leiobuninae, Gagrellinae, Leiobunum, Nelima) are recovered as polyphyletic, although with a phylogenetic structure suggesting a strong association between geography and monophyly as well as notable morphological convergence in traditional diagnostic characters. Phylogenetic affinities between biotas of the New World and Asian tropics, as well as between temperate North American and East Asia, suggest that sclerosmatid historical biogeography may conform with the Boreotropic Concept. Finally, we discuss how the many problems that remain in sclerosomatid systematics might be addressed.