Incipient speciation within the Namalycastis abiuma (Annelida: Nereididae) species group from southern India revealed by combined morphological and molecular data
Memoirs of Museum Victoria Vol 71 p. 169–176 (2014)
Namalycastis abiuma (Grube, 1872), originally described from Brazil, comprises a species complex of morphologically similar forms occurring circumtropically, including India. Apart from the Namalycastis abiuma species group, four other Namalycastis species are presently known from India: N. indica Southern, 1921, N. fauveli Nageswara Rao, 1981, N. glasbyi Fernando & Rajasekaran, 2007, and N. jaya Magesh, Kvist & Glasby, 2012. Recent sampling along the southern Indian coast has uncovered new specimens of the N. abiuma species group. The present study uses combined morphological and molecular data (DNA barcoding) to explore species boundaries within the complex in southwest India and thereby resolve existing taxonomic confusion. In order to evaluate morphological variability within the N. abiuma species group, a total of 50 specimens were sampled from different geographical regions in southern India, and assessed using traditional methods. For 18 of the specimens, a 509 bp fragment of COI, the proposed DNA barcoding gene, was sequenced and subjected to tree reconstruction using both distance methods and maximum parsimony. Based on similarity alone, six different haplotypes were recognized within the dataset and these were also subsequently recovered as six distinct clades in the parsimony analysis. There is significant concordance between the morphotypes and the genetic haplotypes, suggesting that significant structural forces are acting on the specimens at a population level, and that these specimens may even be in an early stage of speciation.
Magesh, M., Kvist, S. & Glasby, C.J., 2014. Incipient speciation within the Namalycastis abiuma (Annelida: Nereididae) species group from southern India revealed by combined morphological and molecular data. Memoirs of Museum Victoria 71: 169-176. http://doi.org/10.24199/j.mmv.2014.71.14
PUBLICATION DATE: 18 December 2014