Population genetic structure and genetic diversity of the threatened White Mountain arctic butterfly (Oeneis melissa semidea)

Abstract

The White Mountain arctic butterfly [WMA;Oeneis melissa semidea (Say)] is endemic to the alpine zone of Mts. Washington and Jefferson, New Hampshire, USA, and because of its small and declining population size, it is considered threatened. White Mountain arctic adults occur only within four alpine meadows, and it has been suggested that dispersal, and hence gene flow, may be restricted among these meadow subpopulations. Furthermore, although the WMA likely is biennial (i.e., requires 2 years for development) like all other species of Oeneis, adults emerge annually. Thus the WMA population may be further structured into two allochronic cohorts, reproductively isolated by their asynchronous adult emergence in either even-or odd-numbered years. We assessed the spatial (among meadows) and temporal (between even-and odd-year cohorts) genetic structure and diversity of the WMA using mtDNA and AFLP markers generated from non-lethally sampled wing and leg tissue. We found no evidence for restricted gene flow among meadows. AFLPs indicated weak differentiation between alternate year cohorts; however, it remains unclear whether this resulted from allochronic reproductive isolation or genetic drift. Despite the WMA's small population size and isolation, levels of AFLP genetic diversity were generally high. Rather than focusing on factors related to population connectivity and adult dispersal, our results suggest that management efforts for the WMA should instead focus explicitly on factors affecting recruitment and mortality.

High genetic drift in endangered northern peripheral populations of the Behr's hairstreak butterfly (Satyrium behrii)

“…For example, across 17 species reviewed in the study by Gradish et al (2015), 12 show a considerably higher proportion of polymorphic loci than we observed in the Behr's hairstreak (values ranging from 0.35 to 1.00, compared to a range of 0.19-0.34 in the Behr's hairstreak) and only one species shows a lower value (≤0.17). Among the 14 of those species for which expected heterozygosity (H E ) estimates were also available, nine show higher values than the Behr's hairstreak (values ranging from 0.10 to 0.46 versus a range of 0.07-0.11 in the Behr's hairstreak) and only two species showed lower values (≤0.06) (Gradish et al, 2015). Interestingly, the Behr's hairstreak shows very similar levels of diversity to endangered populations of the Mormon metalmark from southern British Columbia, which are also at their northern range periphery and for which the proportion of polymorphic loci ranges from 0.17 to 0.23 and H E ranges from 0.07 to 0.09 (Crawford et al, 2011).…”

The role of allochrony in speciation

“…Some organisms have a two‐year life cycle, with individuals that breed in alternate years being reproductively separated from each other. The White Mountain arctic butterfly ( Oeneis melissa semidea ), a threatened butterfly endemic to four sedge meadows in New Hampshire, USA, provides an example (Gradish, Keyghobadi, & Otis, ). While no genetic differentiation was found between meadows, sympatric allochronic cohorts exhibit moderate differentiation (Gradish et al., ).…”

“…The White Mountain arctic butterfly ( Oeneis melissa semidea ), a threatened butterfly endemic to four sedge meadows in New Hampshire, USA, provides an example (Gradish, Keyghobadi, & Otis, ). While no genetic differentiation was found between meadows, sympatric allochronic cohorts exhibit moderate differentiation (Gradish et al., ). Pink salmon ( O. gorbuscha ) provide another example of populations breeding in alternate years, in addition to seasonal allochrony (above); yearly cohorts are genetically differentiated, and genetic differentiation is stronger between cohorts than among populations breeding within the same year in different rivers (Aspinwall, ).…”

Effect of Climatic Conditions and Land Cover on Genetic Structure and Diversity of Eunica tatila (Lepidoptera) in the Yucatan Peninsula, Mexico

“…In addition, microsatellites are inherently difficult to use in butterflies, partially due to the high frequency of null alleles [49]. Therefore, ISSR genetic markers have been widely applied in studies on butterfly population genetic [15][16][17]43,48,[50][51][52][53][54][55][56][57].…”