ABSTRACT
The proliferation of DNA data is revolutionizing all fields of systematic research. DNA barcode sequences, now available for millions of specimens and several hundred thousand species, are increasingly used in algorithmic species delimitations. This is complicated by occasional incongruences between species and gene genealogies, as indicated by situations where conspecific individuals do not form a monophyletic cluster in a gene tree. In two previous reviews, non-monophyly has been reported as being common in mitochondrial DNA gene trees. We developed a novel web service "Monophylizer" to detect non-monophyly in phylogenetic trees and used it to ascertain the incidence of species non-monophyly in COI (a.k.a. cox1) barcode sequence data from 4977 species and 41,583 specimens of European Lepidoptera, the largest data set of DNA barcodes analyzed from this regard. Particular attention was paid to accurate species identification to ensure data integrity. We investigated the effects of tree-building method, sampling effort, and other methodological issues, all of which can influence estimates of non-monophyly. We found a 12% incidence of non-monophyly, a value significantly lower than that observed in previous studies. Neighbor joining (NJ) and maximum likelihood (ML) methods yielded almost equal numbers of non-monophyletic species, but 24.1% of these cases of non-monophyly were only found by one of these methods. Non-monophyletic species tend to show either low genetic distances to their nearest neighbors or exceptionally high levels of intraspecific variability. Cases of polyphyly in COI trees arising as a result of deep intraspecific divergence are negligible, as the detected cases reflected misidentifications or methodological errors. Taking into consideration variation in sampling effort, we estimate that the true incidence of non-monophyly is â¼23%, but with operational factors still being included. Within the operational factors, we separately assessed the frequency of taxonomic limitations (presence of overlooked cryptic and oversplit species) and identification uncertainties. We observed that operational factors are potentially present in more than half (58.6%) of the detected cases of non-monophyly. Furthermore, we observed that in about 20% of non-monophyletic species and entangled species, the lineages involved are either allopatric or parapatric-conditions where species delimitation is inherently subjective and particularly dependent on the species concept that has been adopted. These observations suggest that species-level non-monophyly in COI gene trees is less common than previously supposed, with many cases reflecting misidentifications, the subjectivity of species delimitation or other operational factors.
Subject(s)
Classification/methods , Lepidoptera/classification , Lepidoptera/genetics , Phylogeny , Animals , Bias , DNA Barcoding, Taxonomic , DNA, Mitochondrial , Genes, MitochondrialABSTRACT
A new species, Piarosoma arunachalensis sp. nov., is described and illustrated based on external characters and the genitalia of two male specimens from Tale Wildlife Sanctuary, Lower Subansiri District, Arunachal Pradesh, India. The new species is distinguished from other Piarosoma by a combination of: a) presence of large hyaline patches on the wings, b) the absence of any white or yellow markings on the patagia and the abdominal segments, and c) differences in male genitalia.
Subject(s)
Lepidoptera , Moths , Male , Animals , Genitalia , Genitalia, Male , India , Animals, WildABSTRACT
Based on morphological and molecular data, Ino budensis var. mollis Grum-Grshimailo, 1893, from China, so far treated as a synonym of Jordanita (Roccia) paupera (Christoph, 1887), is here recognized as a good species, Jordanita (Roccia) mollis (Grum-Grshimailo, 1893), stat. nov. This species is recorded as new for the fauna of Russia and Korea. An identification key for this species is provided.
Subject(s)
Lepidoptera , Animals , China , Asia, Eastern , Republic of Korea , RussiaABSTRACT
Levuana iridescens Bethune-Baker, 1906, a day-flying moth purported to be endemic to the Fijian Island of Viti Levu and a former pest of its coconut palm trees, was last observed in 1956 and has been officially declared extinct by IUCN since 1996. The controversial classical biological control method that resulted in the (presumed) demise of this moth has given this species an iconic status in biological control studies. We investigated the sister-group relationships and phylogenetic placement of this moth using NGS-obtained ancient DNA sequences from museum specimens of L. iridescens collected in the 1920s, combined with 31 morphological characters used in earlier studies and 2 new characters. Our findings show that Levuana is most closely related to the Australian genus Myrtartona. The significance of these findings is discussed.
Subject(s)
Extinction, Biological , Moths/anatomy & histology , Moths/classification , Animals , Australia , Female , Male , PhylogenyABSTRACT
The karyotype of the blue butterflies from the Angarskiy Pass (Crimea), previously attributed to Polyommatus (Agrodiaetus) poseidon (Herrich-Schäffer, 1851), was re-examined. In all 19 studied individuals, we found the haploid chromosome number n = 26, including 7 pairs of relatively large and 19 pairs of relatively small chromosomes. According to the chromosome number and karyotype structure, the studied population does not differ from P. (A.) damocles krymaeus (Sheljuzhko, 1928) from the eastern part of the Crimean Mountains. This result does not confirm the previously formulated hypotheses, according to which (1) two morphologically similar but karyologically different species, P. (A.) poseidon and P. (A.) damocles krymaeus, occur sympatrically in the Crimea and (2) there is hybridization between these taxa on the Angarskiy Pass. Thus, only three species of the subgenus Agrodiaetus Hübner, 1822 have been reliably established for the Crimea: P. (A.) damone pljushtchi Lukhtanov & Budashkin, 1993, P. (A.) damocles krymaeus (Sheljuzhko, 1928) and P. (A.) ripartii budashkini Kolev & de Prins, 1995.