Molecular Identification of Necrophagous Dermestes Species in South Korea Using Cytochrome c Oxidase Subunit I Nucleotide Sequences (Genus Dermestes)

Development of Dermestes tessellatocollis Motschulsky under different constant temperatures and its implication in forensic entomology

Dermestidae generally appears on dry corpses and carcasses, especially if mummified or skeletonized. They are forensically important insect species for estimating longer postmortem intervals (PMI). As they develop, Dermestidae larvae undergo multiple larval ecdyses; however, a lack of guidelines for determining the larval instar limits their forensic application. Herein, we explored how temperature impacts the development of Dermestes tessellatocollis Motschulsky, 1860 (Coleoptera: Dermestidae). At seven constant temperatures (16, 19, 22, 25, 28, 31, and 34 °C), the developmental time from egg to adult was 163.87 ± 9.19, 103.56 ± 3.02, 63.59 ± 2.88, 51.49 ± 2.74, 47.86 ± 3.01, 44.62 ± 4.65, and 41.80 ± 4.87 days respectively. Four morphological indexes, including head capsule width, pronotum width, mesonotum width, and body length, were taken in vivo at regular intervals to identify methods for larval instar determination in D. tessellatocollis. The acquired morphological data were used to simulate fitted curves and equations depicting the relationship between the four morphological indexes and instars. From the validation experiment, we could hardly determine a specific instar based on the morphological indexes. The combination of morphometric data (head capsule, pronotum, and mesonotum width) generated the classification accuracy at 100%, 87.5%, 85%, and 93% for the 1st, 2nd/3rd, 4th/5th, and 6th/7th instars, respectively. Nevertheless, the accuracy was unsatisfactory for application in forensic casework. This study provides fundamental development data for adopting D. tessellatocollis in minimum postmortem interval (PMI_min) estimations; however, further studies are needed to improve the classification accuracy for the larval instar determination.

The phylogenetic position of Arhaphe deviatica within Hemipteran insects: A potential model species for eco-devo studies of symbiosis

Insecta is known to be the most diverse group of species, exhibiting numerous forms of endosymbiotic associations. Molecular techniques have provided significant indicators for insect-microbe interactions. The present study aimed to register one of the true bugs of pentatomomorpha and clarify its taxonomic position through phylogenetic analysis of the partial 16S rRNA gene region. A maximum likelihood analysis retrieved a generally well-supported phylogeny based on Tamura 3-parameter model. Based on the partial mitochondrial 16S rRNA gene sequences, a phylogenetic study of suborder Heteroptera relationships within Hemipteras' order was constructed. Sequences of 221 bases of the 3' end of the gene from 28 species within 16 families were analyzed. This analysis and bootstrap confidence revealed two major clades comprising four suborders within Hemiptera, with a close relationship between Heteroptera + (Sternorrhyncha + (Auchenorrhycha + Coleorrhyncha)). Infraorder Pentatomomorpha is forming a sister group with a substantial bootstrap value to Cimicomorpha. Pyrrhocoroidea forms a sister relationship with Lygaeoidea + Coreoidea. There is a close relationship between Largidae and Pyrrhocoridae within Pyrrhocoroidea. The results show that the present species is firmly embedded in the genus Arhaphe with 94.35% sequence resemblance to its congeners. Besides, the recovered hemipteran species considered a potential model group for studying different symbionts. We propose both phylogenetic and ecological evolutionary developmental biology viewpoints for a more synthetic understanding of insect populations' molecular evolution.

Comparative mitochondrial genomics of five Dermestid beetles (Coleoptera: Dermestidae) and its implications for phylogeny

Dermestid beetles (Coleoptera: Dermestidae) are important pests of various stored products, posing potential threats to international trade. Their detailed characterization on molecular basis is a pre-requisite for proper identification and for understanding of their phylogenetic relationships. In this work, the whole mitochondrial genomes (mitogenomes) of Trogoderma granarium, Dermestes lardarius, D. ater, Attagenus augustatus augustatus and Attagenus unicolor japonicus were firstly sequenced to update the database using the next-generation sequencing technique. Based on the selected model species, a comparative analysis of four Dermestidae genera was performed. The mitochondrial genomes of these five species above showed high similarity in nucleotide composition, base composition and gene order, including 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs) and a non-coding control region, which was similar to most of Coleoptera species. The phylogenetic analysis based on the PCGs and two rRNAs indicated that the relationships within Dermestidae were reconstructed as (((Trogoderma + Anthrenus) + Attagenus) + Dermestes) using both Maximum Likelihood (ML) and Bayesian Inference (BI) analysis. However, more mitogenomes should be sequenced to obtain a more holistic view of the whole family. This study not only showed the mitogenomes of five Dermestidae species and their high conservativeness, but also discussed its implications for reconstructing a more comprehensive phylogeny of dermestids.