Development of twenty-four novel microsatellite markers for the freshwater crayfish, Geocharax gracilis, using next generation sequencing
- 267 Downloads
The crayfish Geocharax gracilis is an important inhabitant of natural and agricultural drainage systems in south-eastern Australia. To investigate population structure, genetic diversity and patterns of connectivity in natural and human-altered ecosystems, we isolated and characterised 24 microsatellite loci using next generation sequencing. Loci were initially tested for levels of variation based on 12 individuals from across the species’ geographical range. A further 33 individuals from a single population were used to test for departures from Hardy–Weinberg equilibrium and linkage disequilibrium. We detected high to moderate levels of genetic variation across most loci with a mean allelic richness of 8.42 and observed heterozygosity of 0.629 (all samples combined). We found no evidence for linkage disequilibrium between any loci and only three loci (Geo01, Geo24 and Geo47) showed significant deviations from Hardy–Weinberg expectations. These same three loci, plus two additional loci (Geo06 and Geo28), also showed the presence of null alleles. These 24 variable markers will provide an important tool for future population genetic assessments in natural and human altered environments.
KeywordsCrustacean Dispersal Genetic structure Mating system Gene flow
We would like to thank A. Miller and A. Fitch for technical assistance. A Deakin University Central Research Grant Scheme grant, awarded to DI, CDHS and MS, supported this research.
- Casas JJ, Sanchez-Oliver JS, Sanz A, Furne M, Trenzado C, Juan M, Paracuellos M, Suarez MD, Fuentes F, Gallego I, Gil C, Ramos-Miras JJ (2011) The paradox of the conservation of an endangered fish species in a Mediterranean region under agricultural intensification. Biol Conserv 144:253–262CrossRefGoogle Scholar
- Raymond M, Rousset F (1995) Genepop (version-1.2)—population-genetics software for exact tests and ecumenicism. J Hered 86:248–249Google Scholar
- Rozen S, Skaletsky HJ (2000) Primer3 on the WWW for general users and for biologist programmers. In: Krawetz S, Misener S (eds) Bioinformatics methods and protocols: methods in molecular biology. Humana Press, Totowa, pp 365–386Google Scholar
- Schultz MB, Ierodiaconou DA, Smith SA, Horwitz P, Richardson AMM, Crandall KA, Austin CM (2008) Sea-level changes and palaeo-ranges: reconstruction of ancient shorelines and river drainages and the phylogeography of the Australian land crayfish Engaeus sericatus Clark (Decapoda: Parastacidae). Mol Ecol 17:5291–5314PubMedCrossRefGoogle Scholar