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Abstract Sexual size variation in adult holometabolous insects may arise from selective pressures impacting ontogenetic stages associated with diverse habitats and resource use. In addition, scaling relations of these sexually dimorphic traits play an important role in morphological diversification. In mosquitoes, given the sexual differences in feeding strategies, investigations of the ontogeny of sexually dimorphic traits are of particular interest to understanding their reproductive biology and implementing early sex‐separating technologies for vector control. However, our current knowledge of the morphological scaling of body parts over development across sexes is centered around a few well‐known species of anthropophilic mosquitoes. In general, there is a noticeable gap in our understanding of the developmental biology of mosquitoes with limited medical consequences. One such mosquito isUranotaenia lowii(Diptera: Culicidae), a species of growing interest due to its unique host use of feeding exclusively on frogs by eavesdropping on their mating calls. This study takes a step forward toward filling this gap by investigating sexual size dimorphism during the ontogeny ofUr. lowii. We examined larval and pupal stages to focus on traits that allow sex identification to evaluate various sex‐sorting techniques that provide a foundation for experimental manipulation. We found that sex identification inUr. lowiiis possible during both larval and pupal stages. In the fourth larval instar, thorax length, abdomen length, and total body length differ significantly between the sexes, showing allometric scaling. In the pupal stage, the allometry of the head and thorax to body size remains consistent, as these parts fuse into the cephalothorax. Successful sorting based on cephalothorax length enables highly accurate pupal sex identification. This research sheds light on the biology ofUr. lowii,an understudied mosquito species, and lays the foundation for future studies on the developmental and reproductive biology of frog‐biting mosquitoes.
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Rearing and Shipping of Uranotaenia lowii, a Frog-Biting Mosquito
Many studies on mosquito biology rely on laboratory-reared colonies, emphasizing the need for standardized protocols to investigate critical aspects such as disease biology, mosquito behavior, and vector control methods. While much knowledge is derived from anthropophilic species from genera like Anopheles, Aedes, and Culex, there is a growing interest in studying mosquitoes that feed on non-human hosts. This interest stems from the desire to gain a deeper understanding of the evolution of diverse host range use and host specificity. However, there is currently a limited number of comprehensive protocols for studying such species. Considering this gap, we present a protocol for rearing Uranotaenia lowii, a mosquito species specialized in feeding on anuran amphibians by eavesdropping on host-emitted sound cues. Additionally, we provide instructions for successfully shipping live specimens to promote research on this species and similar ones. This protocol helps fill the current gap in comprehensive guidelines for rearing and maintaining colonies of anuran host–biting mosquitoes. It serves as a valuable resource for researchers seeking to establish colonies of mosquito species from the Uranotaeniini tribe. Ultimately, this protocol may facilitate research on the evolutionary ecology of Culicidae, as this family has recently been proposed to have originated from a frog-feeding ancestor.
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- Award ID(s):
- 2054636
- PAR ID:
- 10513262
- Publisher / Repository:
- Bio-protocol LLC
- Date Published:
- Journal Name:
- BIO-PROTOCOL
- Volume:
- 14
- Issue:
- 1346
- ISSN:
- 2331-8325
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.21769/BioProtoc.4996
