| Anaplecta belongs to Anaplectinae,Anaplectidae,Blattoidea,Dictyoptera.The body size of Anaplecta is small.The significant difference from other species of Blattoidea is that the wing has a large appendicular field and can be folded on the back of the body.Anaplecta recently transferred from Blaberoidea to Blattoidea,and it plays an important role on the study of the phylogeny and evolutionary history of Blattoidea.Anaplecta omei is widely distributed in the provinces of southern China,with some morphological variation and uninterrupted morphology with other species,which is a good material for speciation and lineage differentiation.This study aims to determine the boundary between Anaplecta omei and other species of Anaplecta;clarify the genetic diversity,genetic structure,infer the evolutionary histories and the causes of the current geographical distribution patterns of Amaplecta omei,so as provide a reference for further study on the speciation and lineage differentiation mechanism of Blattodea.Therefore,in this study,morphological and DNA barcodes were used to define the species of Anaplecta in China.Then,the genetic diversity and genetic structure of Amaplecta omei were detected by using the principles and methods of phylogeography.In addition,geological events,Quaternary glacial-interglacial cycles,divergence time and population history dynamics were combined to discuss the differentiation of related species and the causes of population historical dynamics.The main findings are as follows:(1)In this study,the existing samples of Anaplecta were examined.Based on morphological characteristics(including male and female external genitalia)and DNA Barcodes(COI,using the molecular species definition method ABGD),the samples with some differences from Anaplecta omei were identified as 3 cryptic species(Anaplecta longihamata Zhu & Che,2022;Anaplecta condensa Zhu & Che,2022;Anaplecta paraomei Zhu & Che,2022),and the remaining 7 species were named and described(Anaplecta ungulata Zhu & Che,2022;Anaplecta anomala Zhu & Che,2022;Anaplecta serrata Zhu & Che,2022;Anaplecta bombycina Zhu & Che,2022;Anaplecta bicruris Zhu & Che,2022;Anaplecta spinosa Zhu & Che,2022 and Anaplecta truncatula Zhu & Che,2022).At the same time,9 known species from mainland China were defined and re-described to supplement the characteristics of the female genitalia.(2)Mitochondrial genome data of 97 samples from 24 geographical populations of Anaplecta omei and 11 samples of related species were obtained in this study.The sequences of Anaplecta omei are 15347～15367 bp in length with 30.3%～30.4% GC contents.Genetic diversity analysis showed that 79 haplotypes were found in 97 samples of Anaplecta omei.The overall haplotype diversity of Anaplecta omei was high(Hd=0.994),but the nucleotide diversity was low(π=0.00371).(3)Based on bayesian analysis of genetic population structure(BAPS),phylogenetic analysis and haplotype network diagram,the samples of Anaplecta omei were divided into four lineages: GDQLS,HNDPL,Southwest and Southeast.The analysis of molecular variance(AMOVA)showed that most of the genetic variation among lineages.The genetic differentiation index Fst values showed that the genetic differentiation among all lineages and most populations was significant(Fst>0.25),gene communication was scarce.(4)The analysis of divergence time indicated that the divergence of the four species(A.omei,A.paraomei,A.longihamata and A.condensa)mainly occurred in the late Miocene(6.31 ～13.94 Ma),when the mountains around the Tibetan Plateau were continuously uplifting.The divergence of lineages within the species of Anaplecta omei mainly occurred in the early Pleistocene or early Middle Pleistocene,when the climate was turbulent.The lineages of GDQLS and the other three diverging at 1.64 Ma [95% CI: 1.04～2.35 Ma].Subsequently,the lineage of HNDPL(0.83 Ma,95%CI: 0.53～1.18 Ma)diverged.The time of divergence between the southeast and southwest lineages(0.62 Ma,95%CI: 0.40～0.88 Ma)was consistent with Wangkun Glaciation(0.5～0.7 Ma).(5)The population history dynamic dection results showed that the southeast and southwest lineages had experienced population expansion.The southeast lineage expanded during 40～50 Ka,when the climatic conditions were similar to the present;while the southwest lineage obviously expanded before the Last Glacial Maximum(20～30 Ka).Based on the above research results,the main conclusions are as follows: 1)Morphological characteristics,including male and female genitalia,combined with DNA barcodes can accurately distinguish Anaplecta omei and related species,and female genitalia can be used for auxiliary identification of Anaplecta;2)The existing genetic diversity level of Anaplecta omei may have been formed by population expansion in Pleistocene;3)Geographical barrier and heterogeneity of living environment had a great influence on the divergence and genetic structure of Anaplecta omei;4)The continuous uplift of Qinghai Tibet Plateau and the Hengduan Mountains may have affected the divergence of Anaplecta omei and the related species;the Pleistocene climate turbulence may have an important impact on the divergence of each lineage;5)The contraction and expansion of the last glacial period were the important driving force of the population migration of Anaplecta omei. |
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