A comprehensive DNA sequence library is essential for identification with DNA barcodes

In this study we examine the possibility of utilising partial cox 1 gene sequences as barcodes to identify non-biting midges (Diptera: Chironomidae). We analysed DNA from 97 specimens of 47 species in the genera Cladotanytarsus, Micropsectra, Parapsectra, Paratanytarsus, Rheotanytarsus, Tanytarsus and Virgatanytarsus with a main focus on Micropsectra, Parapsectra and Paratanytarsus. Our findings show that (1) cox I is easily amplified from extracts from different life stages with the standard barcoding primers. (2) Although K2P-distances between con-specific sequences varied up to 4.9%, con-specifics clustered together with 91-100% bootstrap support in maximum parsimony analysis. This indicates that barcodes may be excellent tools to identify species that are already in a cox1 library. (3) Both neighbour joining and maximum parsimony failed to reconstruct monophyletic genera. Thus, if a well-matching cox I sequence is not already available in the library, the prospects of approximately identifying an unknown taxon, even to the correct genus of subtribe Tanytarsina, are not good. (C) 2006 Elsevier Inc. All rights reserved.