The Application of Mitochondrial COI Gene-Based Molecular Identification of Forensically Important Scuttle Flies (Diptera: Phoridae) in Korea

Scuttle fly Megaselia scalaris (Loew) (Diptera: Phoridae) endoparasitoid as a novel biocontrol agent against adult American cockroaches (Periplaneta americana)

The American cockroach, Periplaneta americana (Linnaeus, 1758) (Blattodea: Blattidae), is one of the most common pests that thrive in diverse environments and carries various pathogens, causing critical threats to public health and the ecosystem. We thus report in this study the first observation of decapitated American cockroaches as a result of infestation with scuttle fly parasitoids. Interestingly, behavioral alterations in the form of zombification-like behavior could be observed in cockroaches reared in the laboratory before being decapitated, implying that the insect targets cockroach heads. To identify this parasitoid, cockroaches' corpora were isolated in jars, and apodous larvae were observed. Larvae developed into small coarctate pupae, and adults emerged. The scuttle flies were collected and exhibited tiny black, brown, to yellowish bodies. The fly was initially identified based on its morphological properties as a member of the order Diptera, family Phoridae. To provide further insights into the morphological attributes of the phorid species, the fly was examined using a scanning electron microscope (SEM) and then identified as Megaselia scalaris accordingly. SEM analysis revealed the distinctive structure of M. scalaris concerning the head, mouth parts, and legs. Specifically, the mouth parts include the labrum, labellum, rostrum, and maxillary palps. Although further investigations are still required to understand the complicated relationships between M. scalaris and American cockroaches, our findings provide a prominent step in the control of American cockroaches using M. scalaris as an efficient biological control agent.

Drosophila melanogaster Laboratory Rearing for Wolbachia-Based Control Programs, a Component of Dengue Control

Background

Drosophila melanogaster flies are smooth, low upkeep and safe model organisms, they can be effortlessly used in different fields of life sciences like genomics, biotechnology, genetics, disease model, and Wolbachia-based approaches to fight vectors and the pathogens they transmit.

Methods

Fruit fly specimens were collected in 25 districts (14 provinces) of Iran and their morphological recognition was proven by molecular analysis based on sequence homology of mitochondrial COI barcode region. Essential information and specific requirements were provided for laboratory rearing of D. melanogaster.

Results

Drosophila melanogaster colonies were found in 23 out of 25 districts. Also, five related species coincident with D. melanogaster were reported in this study including D. ananassae/D. parapallidosa, D. hydei, D. repleta, Zaprionus indianus (Diptera: Drosophilidae), and Megaselia scalaris (Diptera: Phoridae). The Iranian D. melanogaster molecular signature and their rearing techniques have been described here. The complete life cycle, from (egg to adult), takes approximately 8 days at 25 °C. Some biological points have been presented with highlighting capturing, rearing, culturing, and embryo collection along with primitive recognition and segregation between females and males have been presented. A recipe for culture media and the quantity of various ingredients have been provided.

Conclusion

This is the first report on the D. repleta and D. ananassae/D. parapallidosa species for the country. Results of this study provide efficient and effective rearing procedures which are requirement for both small-scale for facilitating entomological research and large-scale use in justifiable vector control management such as disease model or Dengue control.

Genetic Identification and Traceability of Insect Meals

Insects have been proposed as a rich alternative source of protein for the partial or total replacement of fishmeal in aquaculture. For maximum safety and effectiveness of insect meals, control of the quality composition of these products is considered mandatory. The aim of this study was the genetic analysis of the composition of commercially available insect meals at the species level. Commercially available Hermetia illucens, Tenebrio molitor and Musca domestica individuals, as well as nine insect meals produced from these species, were analyzed. The genetic identification of insects at the species level was based on a COI fragment, and analysis of the insect meals' composition was performed with the processes of cloning and colony PCR. Genetic analysis indicated that the commercially available larvae morphologically identified as Musca domestica belonged to the species Muscina stabulans. In the commercially available insect meals, no other animal species was identified beyond the expected one. However, in the insect meal produced for research purposes, fungal growth was detected. The used methodology, herein, allows for the qualitative genetic identification of insect meals and could be included in the methods of traceability of products containing insects and other animal species.