Multi-gene Phylogenetic Analysis and Genetic Diversity of Discrete Elytral Color Phenotypes in Menochilus sexmaculatus (Coleoptera: Coccinellidae)

Abstract

The phenotype variations of elytral color patterns are common in ladybird beetles. However, phylogenetic relationships and genetic diversity of discrete color patterns in coccinellids is still poorly known. Here, we present a comprehensive genetic diversity analyses and phylogenetic relationships within seventeen different phenotypes of elytral color patterns in Menochilus sexmaculatus based on two mitochondrial genes, cytochrome oxidase subunit I (COI) and II (COII), and two nuclear genes, carbamoyl phosphate synthetase (CAD) and histone subunit 3 (H3). Results indicated the average genetic distance was 0.005 among the different elytral forms of M. sexmaculatus based on combined dataset, which shows very close genetic relationships among them. Results also showed a high level of haplotype diversity (Hd = 0.902) and the low level of nucleotide diversity (Pi = 0.004). In addition, the number of haplotypes was 17 and the same elytral color patterns of M. sexmaculatus didn’t share the same haplotype. Furthermore, phylogenetic analyses showed all M. sexmaculatus samples formed a single clade, but the identical elytral pattern individuals do not cluster together as no special relationships among different phenotypes individuals. Our systematic analyses illustrated the same elytral forms of M. sexmaculatus do not possess closely-related phylogenetic relationships. However, these clear photographs of different elytral color patterns of M. sexmaculatus and the results of our analyses may prevent our incorrect identification for this species.