Cryptic divergence and strong population structure in the colonial invertebrate Pycnoclavella communis (Ascidiacea) inferred from molecular data
Perez-Portela, R.; Turon, X. (2008). Cryptic divergence and strong population structure in the colonial invertebrate Pycnoclavella communis (Ascidiacea) inferred from molecular data. Zoology (Jena) 111(2): 163-178. https://dx.doi.org/10.1016/j.zool.2007.06.006
In: Zoology (Jena). Fischer: Jena. ISSN 0944-2006; e-ISSN 1873-2720, meer
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| Trefwoorden |
Pycnoclavella communis Pérez-Portela, Duran & Turon, 2007 [WoRMS]
Marien/Kust |
| Author keywords |
Free swimming larvae; Restricted dispersal; COI; Microsatellites; Western Mediterranean |
| Abstract |
We studied sequence variation in the mitochondrial gene cytochrome c oxidase subunit I (COI) for 135 individuals from eight Mediterranean populations of the colonial ascidian Pycnoclavella communis across most of its presently known range of distribution in the Mediterranean. Three haplotypes from Atlantic locations were also included in the study. Phylogenetic, phylogeographic and population genetic analyses were used to unravel the genetic variability within and between populations. The study revealed 32 haplotypes for COI, 29 of them grouped within two Mediterranean lineages of P. communis (mean nucleotide divergence between lineages was 8.55%). Phylogenetic and network analyses suggest the possible existence of cryptic species corresponding to these two lineages. Population genetic analyses were restricted to the five populations belonging to the main genetic lineage, and for these localities we compared the information gleaned from COI sequence data and from eight microsatellite loci. A high genetic divergence between populations was substantiated using both kinds of markers (COI, global Fst=0.343; microsatellite loci, global Fst=0.362). There were high numbers of private haplotypes (COI) and alleles (microsatellites) in the populations studied. Restricted gene flow and inbreeding occur in the present range of distribution of the species. Microsatellite loci showed a strong incidence of failed amplifications, which we attribute to the marked intraspecies variability that hampered the application of these highly specific markers. Our results show important genetic variability at all levels studied, from within populations to between basins, possibly coupled to speciation processes. This variability is attributable to restricted gene flow among populations due to short-distance dispersal of the larvae. |
| Dataset |
- CorMedNet- Distribution and demographic data of habitat-forming invertebrate species from Mediterranean coralligenous assemblages between 1882 and 2019., meer
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