Molecular identification and systematic assessment of Labidocera madurae A. Scott, 1909 (calanoid copepod) from Lakshadweep Archipelago, southwest coast of India, based on mitochondrial COI gene sequences
文摘
Labidocera madurae A. Scott, 1909, belonging to the family Pontellidae, may easily be mistaken for Labidocera pavo Giesbrecht 1889 or Labidocera bataviae A. Scott, 1909. L. madurae is distinguishable from its congeners by the presence of a moderately large and asymmetrical genital segment, with the middle of the right side considerably inflated and with a short anal segment in females, and a short, curved, thumb-like process on the proximal outer margin of the first joint of the right exopodite of the fifth pair of feet, the apical joint of left exopodite elongate and ovate, and twice as long as broad in males. Since Labidocera individuals exhibit close proximity in morphology, there exists the potential for misidentification. Intraspecific distance of L. madurae sequences developed in the present study ranged from 0.2 to 0.9 %, which was adequate to confirm the genetic congruence of the same. This study also supported the differentiation of Labidocera madurae from other individuals of the genus Labidocera. A point of major confusion concerning L. madurae and Labidocera sp. from the Hawaiian region was resolved in this study, as is evident from the molecular inference that L. madurae and Labidocera sp. individuals were the descendants of a common ancestor and close relatives to other individuals within the genus. The present database represents the first molecular data for L. madurae, which will be adaptable for resolving taxonomic ambiguities and inferring phylogenetic relationships of the genus Labidocera.