Species diversity analysis of commercial Mantidis Ootheca samples contaminated by store pests based on DNA metabarcoding

Abstract

Mantidis Ootheca (Sangpiaoxiao, mantis egg case) is a typical multi-origin Chinese medicinal material. The Chinese Pharmacopoeia stipulates that the Mantidis Ootheca originates from three species of Mantis: Tenodera sinensis, Statilia maculate, and Hierodula patellifera. However, Mantidis Ootheca mainly relies on field collection, which leads to confusion of its actual origin in the market. As the clinical use of Mantidis Ootheca with unknown original mantis species will pose potential risks to drug safety, it is necessary to survey the commercially available Mantidis Ootheca origin species. However, as the egg case of Mantis, the morphological characters of Mantidis Ootheca are limited and usually cannot serve as accurate identification tool. DNA barcoding, which is widely used in taxonomic studies of animals, is severely affected by the impact of storage pests and DNA degradation. Thus, this study collected a total of 4580 Mantidis Ootheca and pooled separately Mantidis Ootheca samples according to 18 different sources as DNA samples to analyze the origin diversity of Mantidis Ootheca individuals contaminated by common store pests collected in in the market using DNA metabarcoding, and to provide a basis for quality control of Mantidis Ootheca. 37 Mantis ASVs and 9 Mantis MOTUs were identified through species delimitation, and the high-level intraspecific diversity was depicted as haplotype network plot. Besides Tenodera sinensis and Hierodula patellifera as genuine original mantis species defined in the Chinese Pharmacopoeia, Tenodera angustipennis was also the origin species of these Mantidis Ootheca samples.