Mitochondrial DNA phylogeny and morphological diversity in the genus Mastus (Beck, 1837): a study in a recent (Holocene) island group (Koufonisi, south-east Crete)

Abstract

Three endemic Cretan land snail species of the genus Mastus (Beck, 1837) from the island group of Koufonisi (southeast Crete) and the eastern part of Crete, were studied by multivariate analysis of shell morphology and analysis of mtDNA sequences. The phylogeny of the populations studied and the processes effecting the genetic and morphological diversity of the species were investigated. Extremely high mtDNA sequence divergence was observed both within and between populations. The Cretan populations could not be distinguished morphologically, while the populations of the islets were more distinct. We argue that the active geological past of the area (including sea level changes) and the longterm presence of humans has produced a mixing up of Mastus populations leading to the accumulation of high divergence of mtDNA sequences on a small spatial scale. The limited morphological diversity and the distinct shell 'identity' of the islets' populations can be attributed to the selective pressures of the island group.

Inference of a Radiation in Mastus (Gastropoda, Pulmonata, Enidae) on the Island of Crete

“…The evidently complicated geotectonic history of the Aegean Archipelago has created a complex pattern with a profound effect on the morphological and genetic diversity of the taxa distributed in the area (see Douris et al 1998;Chatzimanolis et al 2003;Parmakelis et al 2003;Poulakakis et al 2003). The documented high levels of diversity exhibited both by vertebrate (Kassapidis 2001;Poulakakis et al 2003) and invertebrate groups (Douris et al 1998;Chatzimanolis et al 2003) present in the Aegean region resulted in a dramatic increase of the number of taxa recorded from the area.…”

“…As most of the variable position turned out to occur in the ITS-2 region, we will refer to this fragment as ITS-2 hereafter for convenience. The PCR conditions and the primers used for the amplification of the mitochondrial gene are described in Parmakelis et al (2003); the amplification of the nuclear genes was done using the primers LSU1 and LSU3 as described in Wade and Mordan (2000). Both strands of the PCR products were sequenced.…”

Inference of a Radiation in Mastus (Gastropoda, Pulmonata, Enidae) on the Island of Crete

“…The evidently complicated geotectonic history of the Ae-gean Archipelago has created a complex pattern with a profound effect on the morphological and genetic diversity of the taxa distributed in the area (see Douris et al 1998;Chatzimanolis et al 2003;Parmakelis et al 2003;Poulakakis et al 2003). The documented high levels of diversity exhibited both by vertebrate (Kassapidis 2001;Poulakakis et al 2003) and invertebrate groups (Douris et al 1998;Chatzimanolis et al 2003) present in the Aegean region resulted in a dramatic increase of the number of taxa recorded from the area.…”

Enhanced colour polymorphisms in island populations of the land snail Euhadra peliomphala

“…It is important to estimate source populations on the mainland of the populations in an oceanic island, and to clarify whether island populations are morphologically more variable than their mainland relatives. Except for very few examples (Johnson, Murray & Clarke, 1993;Parmakelis et al, 2003), however, quantitative studies of this sort are surprisingly scarce, at least with respect to patterns at a low taxonomic level (Schluter, 2000).…”