Monday, December 10, 2007 - 8:29 AM

A test of the monophyly of the genus Pseudosinella (Collembola: Entomobryidae), with comments on speciation and the phylogenetic relevance of some subgeneric diagnostic characters

Joseph Reznik,, University of Vermont, Department of Biology, 120A Marsh Life, Burlington, VT and Felipe N. Soto-Adames,, University of Vermont, Biology, 120A Marsh Life Science Building, 109 Carrigan Drive, Burlington, VT.

A phylogenetic analysis of the North American Lepidocyrtus and Pseudosinella was conducted to assess the monophyly of the genus Pseudosinella, the phylogenetic importance of characters used to diagnose groups of Pseudosinella, and pattern of speciation associated with the invasion of caves. The analysis included 11 species of Lepidocyrtus and eight species of Pseudosinella from the Nearctic, three species from the Neotropics, and one species of Lepidocyrtus from Oceania (Philippines). Seven of the eight species of Pseudosinella include specimens from caves and represent three cave regions in North America (Edwards Plateau, Ozark Plateau, Heartland). The results support a paraphyletic Pseudosinella, suggesting the invasion of caves has been from multiple invasions into cave ecosystems. The invasion of caves by species of Lepidocyrtus and Pseudosinella from the Edwards Plateau supports the Adaptive Shift Hypothesis, while species of Pseudosinella from the Ozark Plateau and the Heartland support the Climatic Relict Model. The characters used to diagnose subgroups of Pseudosinella show high levels of homoplasy and are not phylogenetically important.

Species 1: Collembola Entomobryidae Pseudosinella violenta