Species Delimitation and Phylogenetic Relationships in Ectobiid Cockroaches (Dictyoptera, Blattodea) from China.

We collected Ectobiidae cockroach specimens from 44 locations in the south of the Yangtze valley. We obtained 297 COI sequences specimens and carried out phylogenetic and divergence dating analyses, as well as species delimitation analysis using a General Mixed Yule Coalescent (GMYC) framework. The intraspecific and interspecific sequence divergence in Ectobiidae cockroaches ranged from 0.0 to 7.0% and 4.6 to 30.8%, respectively. GMYC analysis resulted in 53 (confidence interval: 37-65) entities (likelihood ratio = 103.63) including 14 downloaded species. The COI GMYC groups partly corresponded to the ectobiid species and 52 ectobiid species were delimited successfully based on the combination of GMYC result with morphological information. We used the molecular data and 6 cockroach fossil calibrations to obtain a preliminary estimate of the timescale of ectobiid evolution. The major subfamilies in the group were found to have diverged between ~125-110 Ma, and morphospecies pairs were found to have diverged ~10 or more Ma.