Karyotype and COI gene sequences of Chironomus melanotus Keyl, 1961 from the Yaroslavl region, Russia, and the difficulties with its identification using GenBank and BOLD systems

By

Bolshakov, Viktor
Movergoz, Ekaterina

Type

Article

Date of Publication

2022

Original Publication

Comparative cytogenetics : international journal of plant & animal cytogenetics, karyosystematics and molecular systematics

Volume

16

Series / Issue

Issue: 3

Pages

161--172

Subjects

Chironomidae , Chironomus melanotus , COI , dark taxa , DNA-barcode , karyotype

Contributed by

Pensoft Publishers

Language

English

Published by

St. Petersburg, Russia [Published] with technical support of Zoological Institute RAS [2007]-

Identifiers

DOI: https://doi.org/10.3897/compcytogen.v16.i3.90336

 

Abstract

Karyotype and COI gene sequences of Chironomus melanotus Keyl, 1961 from the Yaroslavl region (Russia) were analyzed. A low level of chromosomal polymorphism has been confirmed, eventually eight banding sequences were found: melA1, melB1, melC1, melD1, melE1, melF1, and melG1; only melD2 was found in two larvae from the Sunoga river. Analysis of phylogenetic tree and estimated genetic distances has shown not all COI gene sequences of Ch. melanotus in GenBank and BOLD to belong to this species. The lower distance of 0.4% was observed between two sequences from the Yaroslavl region and Finland, apparently these are true Ch. melanotus sequences. The distances between true Ch. melanotus and other sequences from Finland were 9.5% and 12.4%, and from Sweden it was 11%. The average genetic distance between studied sequences of 9.1% is out of the range of the 3% threshold previously determined for chironomids. According to our estimates, there are two sequences with a distance of 2.9% that may belong to Ch. annularius Meigen, 1818, and one sequence with a genetic distance of 2.1%, may belonging to Ch. cingulatus Meigen, 1830, which has been confirmed karyologically. Another two sequences form a separate cluster. We suggest that they either belong to a known species, but are not present in the databases, or belong to a distinct, undescribed species.