The phylogeography of Indoplanorbis exustus (Gastropoda: Planorbidae) in Asia

Abstract

BackgroundThe freshwater snail Indoplanorbis exustus is found across India, Southeast Asia, central Asia (Afghanistan), Arabia and Africa. Indoplanorbis is of economic importance in that it is responsible for the transmission of several species of the genus Schistosoma which infect cattle and cause reduced livestock productivity. The snail is also of medical importance as a source of cercarial dermatitis among rural workers, particularly in India. In spite of its long history and wide geographical range, it is thought that Indoplanorbis includes only a single species. The aims of the present study were to date the radiation of Indoplanorbis across Asia so that the factors involved in its dispersal in the region could be tested, to reveal potential historical biogeographical events shaping the phylogeny of the snail, and to look for signs that I. exustus might be polyphyletic.ResultsThe results indicated a radiation beginning in the late Miocene with a divergence of an ancestral bulinine lineage into Assam and peninsular India clades. A Southeast Asian clade diverged from the peninsular India clade late-Pliocene; this clade then radiated at a much more rapid pace to colonize all of the sampled range of Indoplanorbis in the mid-Pleistocene.ConclusionsThe phylogenetic depth of divergences between the Indian clades and Southeast Asian clades, together with habitat and parasitological differences suggest that I. exustus may comprise more than one species. The timescale estimated for the radiation suggests that the dispersal to Arabia and to Southeast Asia was facilitated by palaeogeographical events and climate change, and did not require human involvement. Further samples from Afghanistan, Africa and western India are required to refine the phylogeographical hypothesis and to include the African Recent dispersal.

Recent range expansion of an intermediate host for animal schistosome parasites in the Indo-Australian Archipelago: phylogeography of the freshwater gastropod Indoplanorbis exustus in South and Southeast Asia

“…1, 2 and 3). This strongly suggests that proto- Indoplanorbis might have originated in the humid subtropical plains of Nepal or in unstudied southern adjacent areas such as northern India as suggested by Liu et al [30]. It is unlikely that this tropical species group originated in a more northern region where the highland water temperatures are drastically colder and thus inhibit the completion of the life cycle [63].…”

A phylogeny for the pomatiopsidae (Gastropoda: Rissooidea): a resource for taxonomic, parasitological and biodiversity studies

“…The use of MP afforded an analysis free of the assumptions underlying ML methods, and the use of POY with its dynamic homology approach (where characters (transformation series) are inferred during the process of phylogenetic reconstruction) frees the analysis of any effects particular to the alignment inferred by Sequencher [150]. The choice of weighting schemes and run settings used followed published procedures [151]. …”

DNA multigene sequencing of topotypic specimens of the fascioliasis vector Lymnaea diaphana and phylogenetic analysis of the genus Pectinidens (Gastropoda)

“…and C. occulta (AJ626858) (Bargues et al 2006) (Bargues et al 2011a), P. columella (PCU82073) (Remigio & Blair 1997a); (v) mtDNA cox1 gene: S. elodes (AY227368), F. bulimoides (AY227367) and Austropeplea tomentosa (AY227365) (Remigio & Hebert 2003), G. truncatula from Spain (AM494011) (Bargues et al 2007) and Germany (EU818799) (Albrecht et al 2008), L. cubensis cox1a (AM494009) and cox1b (FN182205), L. neotropica cox1a (AM494008) and cox1b (FN356741), L. humilis cox1a, cox1b and cox1c (FN182197-9) (Bargues et al 2007, 2011a, Mera y Sierra et al 2009), P. columella (FN598165) (Bargues et al 2011b) and P. columella (AY227366) (Remigio & Hebert 2003), Radix rubiginosa (GU451737) (Liu et al 2010).…”