Cryptic Taxa Revealed through Combined Analysis of Chromosomes and DNA Barcodes: The Polyommatus ripartii Species Complex in Armenia and NW Iran

Abstract

The detection of cryptic species in complexes that have undergone recent speciation is often difficult, since many standard nuclear markers have not yet accumulated differences between closely related taxa, and differences in mitochondrial markers can be leveled out due to mitochondrial introgressions. In these cases, the use of derived chromosomal characters such as non-ancestral chromosomal numbers and/or unusual karyotype features may be a solution to the species delimitation problem. However, non-ancestral but similar karyotypes may arise secondarily as a result of homoplastic evolution, and their interpretation as homologies may lead to incorrect taxonomic conclusions. In our study, we show that the combined use of mitochondrial DNA barcodes and karyotypes helps to solve this problem and identifies cryptic species in situations where each of these markers does not work individually. Using this approach, we show that the fauna of Armenia and adjacent Iran includes the following cryptic taxa of the Polyommatus ripartii species complex (haploid chromosome number, n in parentheses): P. ripartii paralcestis (n = 90), P. ripartii kalashiani, subsp. nov (n close to 90), P. emmeli, sp. nov. (n = 77–79), P. keleybaricus, sp. nov. (n = 86), P. demavendi belovi (n = 73–75), P. demavendi antonius, subsp. nov. (n = 71–73), P. admetus anatoliensis (n = 79) and P. eriwanensis (n = 29–34). Polyommatus admetus yeranyani is synonymized with P. admetus anatoliensis.