The Complete Mitochondrial Genomes Of Five Satyrid Butterfly Species And Their Phylogenetic Implications

Satyrinae is one of the largest butterfly groups of the lepidopteran family,the Nymphalidae. However, owing to the lack of detailed homologousmorphological and molecular data, the systematic relationships of Satyrinaewith other related nymphalid groups (Amathusiinae and Calinaginae, etc.) andrelations among the main Satyrinae groups (Elymniini, Melanitini and Lethina,etc.) are still standing as controversial issues.The insect mitochondrial DNA (mtDNA) has a circular structure that isabout14to20kb long, containing37mitochondrial genes:13putativeprotein-coding genes (PCGs),2ribosomal RNAs,22transfer RNAs and anon-coding AT-rich region. Owing to its unique characteristics in molecularevolutionary analysis, mtDNA has been widely applied in the study areas ofphylogenetics, comparative and evolutionary genomics, population genetics,ect.In this study, the complete mitochondrial genome (mitogenome) ofCallerebia suroia, Elymnias hypermnestra, Lethe dure, Melanargia asiaticaand Triphysa phryne were sequenced and analyzed using the long PCR and theconserved primer-walking technology. The results showed that the completemitochondrial genome sequences of Callerebia suroia, Elymnias hypermnestra,Lethe dure, Melanargia asiatica and Triphysa phryne were15208bp,15167bp,15259bp,15142bp,15143bp in length, respectively, and all of themcontaining13protein-coding genes (ATP6, ATP8, COI-III, ND1-6, ND4L,Cytb),2ribosomal RNA genes (lrRNA and srRNA),22transfer RNA genesand a AT-rich region. In addition, all the genes in the mitogenomes werearranged in the same order and orientation without rearangement as those ofother lepidopteran species determined.There are10,10,13,11and14intergenic spacer sequences totalling85bp,57bp,89bp,85bp and96bp throughout the C. suroia, E. hypermnestra, L.dure, M. asiatica and T. phryne mitogenomes, respectively, and the largest spacer region were all located between the tRNAGlnand ND2genes. In addition,There are14,13,13,12and8overlapping sequences totalling37bp,38bp,41bp,33bp and28bp throughout the C. suroia, E. hypermnestra, L. dure, M.asiatica and T. phryne mitogenomes, respectively. The large rRNA gene weredetermined to be1347bp,1331bp,1341bp,1336bp and1343bp in lengthwhile, the small rRNA gene were determined to be753bp,768bp,752bp,775bp and775bp in length, in the C. suroia, E. hypermnestra, L. dure, M. asiaticaand T. phryne mitogenomes respectively, respectively. All the tRNA genes havetypical leaf clover secondary structures, except for the tRNASer(AGN), whoseDHU arm forms a simple loop. Except for COI,12out of its13protein codinggenes (PCGs) use standard ATN as start codons; All the PCGs use commonstop codon (TAA/TAG), except for the COI, COII, ND5and ND4genes, whichterminate into a single T. For C. suroia, E. hypermnestra, L. Dure, M. asiaticaand T. phryne, their A+T rich regions are417bp,404bp,432bp,319bp,316bp in length each with their A+T content of94.3%,90.6%,92.3%,81.9%,and83.5%, respectively. and this regions usually contain microsatellite-likerepeating sequences such as (TA)8,(TA)8(AT),(AT)6,(TA)6T(TA),(TA)8(AT)and (TA)4.Recently, molecular phylogenetic analyses indicates that Nymphalidaeshould be divided into five major clades (satyrine clade, nymphaline clade,heliconiine clade, libytheine clade and danaine clade), and the satyrine cladeinclude four subfamilies (Satyrinae, Amathusiinae, Charaxinae andCalinaginae). In order to further clarify the taxonomic stata and phylogeneticrelationships of within and among Satyrine clades, especially among Satyrinaegroups, the phylogenetic trees of the ten representive Satyrine butterfly specieswere reconstructed with the maximum likelihood (ML) and bayesian inference(BI) methods based on the thirteen mitochondrial protein coding gene sequencedata, using a moth species Adoxophyes honmai as the outgroup. The resultsshowed the phylogenetic relationship is:((Calinaginae+Charaxinae)+(Amathusiinae+Satyrinae)); while the phylogenetic relationships within theSatyrinae was that ((Amathusiinae+Elymniini)+(Melanitini+(Satyrini,including Lethina))). In addition, from the view of coevolution, somewhatdegree of correlations were detected between the representative butterfly groups and their larval hostplants in this study. Thus, from the abovemultidisplinary studies, the conlusions could be drawn as follows: the subtribeLethina should be separated from the tribe Elymniini and categorizeded intothe tribe Satyrini, the Amathusiinae should be classified as a tribal taxon withinSatyrinae, which is sister-related to the Elymniini, and the Melanitini is closelyrelated to the Satyrini.