The Orthalicoidea is a dominant faunal element in the Neotropics, but also has a number of genera with a Gondwanan distribution.[1]
Taxonomy
2005 taxonomy
This taxonomy, as accepted by Bouchet & Rocroi, was based on the study by Nordsieck, published in 1986,[3] and the classification as formulated by Schileyko in 1999.[4] However Bouchet & Rocroi diverged from this classification in uniting the families Bulimulidae and Orthalacidae. They also considered the family Placostylidae as a distinct family from Orthalicidae, and the family Coelociontidae a distinct family from Urocoptidae. However, the position of the families Megaspiridae and Grangerellidae is doubtful.[5]
Family Prestonellidae van Bruggen, 1978 - A study by Herbert and Mitchell, published in 2009, places this enigmatic family, of which the phylogenetic relationships were previously unknown, in the Gondwanan superfamily Orthalicoidea,[7] while it was previously tentatively placed as a synonym of Aillyidae.[5]
Breure & Romero (2012)[9] confirmed previous results from 2010, additionally they elevated Simpulopsini to Simpulopsidae, renamed Placostylidae to Bothriembryontidae.[9] Therefore, there are recognized seven extant[9] families and one extinct[5] family within Orthalicoidea:
^Nordsieck H. (1986). "The system of the Stylommatophora (Gastropoda), with special regard to the systematic position of the Clausiliidae, II. Importance of the shell and distribution". Archiv für Molluskenkunde. 117 (1–3): 93–116.
^Schileyko A. A. (1998–2003). "Treatise on recent terrestrial pulmonate molluscs". Ruthenica. suppl. 2: 1–1626.
^Uit de Weerd D. R. (2008). "Delimitation and phylogenetics of the highly diverse land snail family Urocoptidae (Gastropoda, Pulmonata) based on 28S rRNA sequence data: A reunion with Cerion". Journal of Molluscan Studies74: 317-329. doi:10.1093/mollus/eyn023.
^ abcBreure A. S. H., Groenenberg D. S. J. & Schilthuizen M. (2010). "New insights in the phylogenetic relations within the Orthalicoidea (Gastropoda, Stylommatophora) based on 28S sequence data". Basteria74(1-3): 25-31.
Borrero F. J. & Breure A. S. H. (Submitted). "The Orthalicoidea (Mollusca: Gastropoda: Stylommatophora) from Colombia and adjacent areas: a review of taxonomy and biogeography. 1. Dryptus Albers, 1860 and Plekocheilus Guilding, 1828".