Genetic diversity and differentiation among populations of the Indian eri silkworm, Samia cynthia ricini, revealed by ISSR markers

Samia cynthia ricini (Lepidoptera:Saturniidae), the Indian eri silkworm, contributes significantly to the production of commercial silk and is widely distributed in the Brahmaputra river valley in North-Eastern India. Due to over exploitation coupled with rapid deforestation, most of the natural populations of S. cynthia ricini are dwindling rapidly and its preservation has become an important goal. Assessment of the genetic structure of each population is a prerequisite for a sustainable conservation program. DNA fingerprinting to detect genetic variation has been used in different insect species not only between populations, but also between individuals within a population. Since, information on the genetic basis of phenotypic variability and genetic diversity within the S. cynthia ricini populations is scanty, inter simple sequence repeat (ISSR) system was used to assess genetic diversity and differentiation among six commercially exploited S. cynthia ricini populations. Twenty ISSR primers produced 87% of inter population variability among the six populations. Genetic distance was lowest between the populations Khanapara (E5) and Mendipathar (E6) (0.0654) and highest between Dhanubhanga (E4) and Titabar (E3) (0.3811). Within population, heterozygosity was higher in Borduar (E2) (0.1093) and lowest in Titabar (E3) (0.0510). Highest gene flow (0.9035) was between E5 and E6 and the lowest (0.2172) was between E3 and E5. Regression analysis showed positive correlation between genetic distance and geographic distance among the populations. The high GST value (0.657) among the populations combined with low gene flow contributes significantly to the genetic differentiation among the S. cynthia ricini populations. Based on genetic diversity, these populations can be considered as different ecotypes and in situ conservation of them is recommended

Demonstration of reproductive isolating mechanisms in Callosamia (Saturniidae) by artificial hybridization

Volume: 19Start Page: 72End Page: 8

The John T. Mason Collection at Denver Museum of Natural History

Volume: 44Start Page: 194End Page: 19

PARASITOID AND HOST PLANT RECORDS FOR GENUS SCHINIA NOCTUIDAE IN TEXAS USA

Volume: 42Start Page: 144End Page: 14

The John T. Mason Collection at Denver Museum of Natural History

Volume: 44Start Page: 194End Page: 19

Two notable range extensions for Callosamia secuifera (Saturniidae) in Georgia and South Carolina

Volume: 35Start Page: 247End Page: 24

The life history of Hemileuca magnifica (Saturniidae) with notes on Hemileuca hera marcata

Volume: 26Start Page: 225End Page: 23

Data from: Phylogenomics supports incongruence between ecological specialization and taxonomy in a charismatic clade of buck moths

Local adaptation can be a fundamental component of speciation, but its dynamics in relation to gene flow are not necessarily straightforward. Herbivorous taxa with localized host plant or habitat specialization across their geographic range are ideal models for investigating the patterns and constraints of local adaptation and its impact on diversification. The charismatic, day-flying moths of the Hemileuca maia species complex (Lepidoptera: Saturniidae) are such taxa, as they are geographically-widespread, exhibit considerable ecological and morphological variability and host and habitat specificity, but apparently lack genetic differentiation across their range. Here, we use genome-wide single nucleotide polymorphisms to assess relationships and population structure of this group across North America, and investigate the scales where genomic divergence correlates with adaptive ecological characteristics. In contrast to previous genetic studies of the group, we find broad- and fine-scale genetic differentiation between lineages, which is at odds with various levels of taxonomic description and recognition of conservation units. Furthermore, ecological specialization only explains some fine-scale genetic differentiation, and across much of the group’s range, local adaptation is apparently occurring in the face of strong gene flow. These results provide unprecedented insight into drivers of speciation in this group, the relationship between taxonomy and genomics-informed species boundaries, and conservation management of internationally-protected entities. Broadly, this system provides a model for understanding how local adaptation in an herbivore can arise and be maintained in the face of apparently strong gene flow, and the importance of geographic isolation in generating genomic divergence, despite a lack of ecological divergence