Assessing genetic diversity, fine-scale population structure, and demographics in the narrow endemic chittenango ovate amber snail (Novisuccinea chittenangoensis)

Abstract

We document isolation and characterization of 12 tetra-nucleotide microsatellite DNA markers in the hermaphroditic Chittenango ovate amber snail ( Novisuccinea chittenangoensis ) endemic to Chittenango Falls in central New York State, USA. The markers displayed a moderate level of allelic diversity (averaging 5.2 alleles/locus) and heterozygosity (averaging 58.6%) in the single extant population. Allelic diversity was sufficient to produce unique multilocus genotypes; no indication of selfing was observed among this cosexual species. Minimal deviations from Hardy–Weinberg equilibrium and no linkage disequilibrium were observed when three collections, representing different rock ledge heights, were analyzed separately. A series of analyses identified weak population differentiation among the ledge collections. Demographic analyses suggested each collection has achieved mutation-drift equilibrium. The microsatellite markers developed for N. chittenangoensis yielded sufficient genetic diversity to: (i) distinguish all individuals and assess the level of selfing; (ii) elucidate fine-scale population structuring; and (iii) provide unique demographic perspectives for recovery efforts.