mtCOI barcoding of true bugs from Western Ghats of India is reported.
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Study includes 9 families and 73 species; 43 from present work and 30 from GenBank.
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mtCOI barcodes can be used for species level identification of unknown bug taxa.
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Species identification even at nymphal stage could be achieved with this technique.
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Present study adds 41 new mtCOI sequences to the existing global database.
Abstract
Recent studies from East Asia and Canadian National Collection of Insects have established the utility of DNA barcoding technique in identification of true bugs. The present study is an expansion of the database by adding mitochondrial cytochrome c oxidase I (mtCOI) sequences from forty three species of indigenous true bugs of India. mtCOI gene analysis of infraorder Pentatomomorpha covering a total of seventy three species that belong to five superfamilies; Pentatomoidea, Coreoidea, Pyrrhocoroidea, Lygaeoidea and Aradoidea revealed more than 3% interspecific distances in all the taxa studied except for two cases which showed barcode sharing. Less than 2% intra-specific divergence was observed in 97% of the taxa analysed and the average interspecies genetic distance was about 29 times higher than the average intraspecies genetic divergence. Distinct sequence divergence pattern at generic level and NJ clustering analysis suggests that COI barcode is an excellent molecular marker for species level identification of unknown taxa; however it may not be useful for resolving deep levels of divergence. Species identification even at nymphal stage could be achieved confirming the efficacy of this technique.
Graphical abstract
Fig. 1. NJ tree based on mtCOI from Cyclopelta siccifolia in three different life stages; egg, nymph and adult. Two Cimicomorpha taxa Rhynocoris marginatus and Rhynocoris ornatus are used as outgroups.
Abbreviations
COI
Cytochrome c oxidase I
CBOL
Consortium for the Barcode of Life
iBOL
International Barcode of Life, dNTPs, deoxynucleotide triphosphates
EtBr
Ethidium bromide
PEG
Polyethylene glycol
K2P
Kimura-2-parameter
NCBI
National Centre for Biological Information
BLAST
Basic local alignment search tool, MEGA, Molecular evolutionary genetics analysis