Woodroaches from the genus Cryptocercus Scudder, 1862 are known to display low levels of morphological divergence, yet significant genetic divergence and variability in chromosome number. Compared with Cryptocercus taxa from North America, the diversity of the genus in Asia has received relatively little attention. We performed morphological and karyotypic examinations of multiple taxa from several previously unsampled mountainous areas of central and south-western China, and identified nine candidate species primarily on the basis of chromosome number. We then investigated diversity across all Asian Cryptocercus, through phylogenetic analyses of 135 COI sequences and 74 28S rRNA sequences from individuals of 28 localities, including species delimitation analysis in General Mixed Yule Coalescent (GMYC) and Automatic Barcode Gap Discovery (ABGD). Phylogenetic results indicated that individuals from the same locality constituted well supported clades. The congruence of GMYC and ABGD results were in almost perfect accord, with 28 candidate species described on the basis of karyotypes (including the nine identified in this study). We provide evidence that each valley population in the Hengduan Mountains contains a separate evolving lineage. We conclude that the principal cause of the rich Cryptocercus diversity in China has been the uplift of the Qinghai-Tibet Plateau.
Morphological characteristics, including male and female genitalia, combined with DNA barcodes were used to identify 470Anaplectaspecimens sampled from China. TenAnaplectaspecies are new to science, including three cryptic species:A. paraomeiZhu & Che,sp. nov.,A. condensaZhu & Che,sp. nov., andA. longihamataZhu & Che,sp. nov., which are distinguished mainly by their female genitalia. The other seven new species are as follows:A. bicrurisZhu & Che,sp. nov.,A. spinosaZhu & Che,sp. nov.,A. ungulataZhu & Che,sp. nov.,A. anomalaZhu & Che,sp. nov.,A. serrataZhu & Che,sp. nov.,A. bombycinaZhu & Che,sp. nov., andA. truncatulaZhu & Che,sp. nov.This study illustrates that differences in female genitalia can be used to distinguish among species ofAnaplecta. The female genitalia of 19 ChineseAnaplectaspecies are described and illustrated in this paper.
In this study, we examine 500 specimens of Anaplecta collected from China, of which 26 samples were used for COI sequencing. We confirm eight new species, i.e., Anaplecta corneola Deng & Che sp. nov., Anaplecta staminiformis Deng & Che sp. nov., Anaplecta arcuata Deng & Che sp. nov., Anaplecta strigata Deng & Che sp. nov., Anaplecta furcata Deng & Che sp. nov., Anaplecta cruciata Deng & Che sp. nov., Anaplecta nigra Deng & Che sp. nov. and Anaplecta bicolor Deng & Che sp. nov. based on morphological and molecular data using ABGD and GMYC analyses. The results of ABGD and GMYC were basically consistent with the morphospecies of Anaplecta. The intraspecific and interspecific genetic distances of Anaplecta ranged from 0 to 6.6% and 16.8% to 31.8%, respectively. We found the male genitalia of Anaplecta to exhibit intraspecific variation, especially in the phallomeres.
This study examined 504 Rhabdoblatta specimens sampled from China, of which, 86 Rhabdoblatta specimens were used for COI sequencing. A phylogenetic analysis using the ML method and MOTUs estimations by ABGD and GMYC based on COI sequences was performed. Eighteen Rhabdoblatta species were identified when these data were combined with morphological data. Six new species were established among these samples, i.e., Rh.similsinuatasp. n., Rh.densimaculatasp. n., Rh.gyroflexasp. n., Rh.chaulformissp. n., Rh.maculatasp. n., and Rh.ecarinatasp. n. For the first time, females including female genitalia of 14 known Rhabdoblatta species are described worldwide. Our study shows that combining molecular species delimitation methods with morphological data helps to delimit species and understand cockroach biodiversity.
In this study, the complete mitochondrial genome of Cryptocercus meridianus was sequenced. The circular mitochondrial genome is 15,322 bp in size and contains 13 protein-coding genes, two ribosomal RNA genes (12S rRNA and 16S rRNA), 22 transfer RNA genes, and one D-loop region. We compare the mitogenome of C. meridianus with that of C. relictus and C. kyebangensis. The base composition of the whole genome was 45.20%, 9.74%, 16.06%, and 29.00% for A, G, C, and T, respectively; it shows a high AT content (74.2%), similar to the mitogenomes of C. relictus and C. kyebangensis. The protein-coding genes are initiated with typical mitochondrial start codons except for cox1 with TTG. The gene order of the C. meridianus mitogenome differs from the typical insect pattern for the translocation of tRNA-SerAGN, while the mitogenomes of the other two Cryptocercus species, C. relictus and C. kyebangensis, are consistent with the typical insect pattern. There are two very long non-coding intergenic regions lying on both sides of the rearranged gene tRNA-SerAGN. The phylogenetic relationships were constructed based on the nucleotide sequence of 13 protein-coding genes and two ribosomal RNA genes. The mitogenome of C. meridianus is the first representative of the order Blattodea that demonstrates rearrangement, and it will contribute to the further study of the phylogeny and evolution of the genus Cryptocercus and related taxa.