Ecological Drivers and Sex-Based Variation in Body Size and Shape in the Queensland Fruit Fly, Bactrocera tryoni (Diptera: Tephritidae)

Abstract

The Queensland fruit fly (Bactrocera tryoni; Q-fly) is an Australian endemic horticultural pest species, which has caused enormous economic losses. It has the potential to expand its range to currently Q-fly-free areas and poses a serious threat to the Australian horticultural industry. A large number of studies have investigated the correlation between environmental factors and Q-fly development, reproduction, and expansion. However, it is still not clear how Q-fly morphological traits vary with the environment. Our study focused on three morphological traits (body size, wing shape, and fluctuating asymmetry) in Q-fly samples collected from 1955 to 1965. We assessed how these traits vary by sex, and in response to latitude, environmental variables, and geographic distance. First, we found sexual dimorphism in body size and wing shape, but not in fluctuating asymmetry. Females had a larger body size but shorter and wider wings than males, which may be due to reproductive and/or locomotion differences between females and males. Secondly, the body size of Q-flies varied with latitude, which conforms to Bergmann’s rule. Finally, we found Q-fly wing shape was more closely related to temperature rather than aridity, and low temperature and high aridity may lead to high asymmetry in Q-fly populations.

Morphometrics of Adult Chinese Citrus Fly Bactrocera minax (Enderlein) (Diptera: Tephritidae) in Nepal

“…Drew et al, 2007 described a morphological description of the adult Chinese citrus fly, noting that the fly is likely the biggest of all Bactrocera species. Ecological situation may be a key factor that influence in the morphological characteristics such as body shape and size of fruit flies within the species (Zhou, 2020). The larval diet and nutritional content are thought to be the most critical variables determining juvenile growth and eventual adult body size.…”

Host effect on morphology of the fruit fly Anastrepha zenildae (Diptera: Tephritidae) from the Semi‑Arid region of Rio Grande do Norte

“…The flies from our work also showed sexual dimorphism in size for Guava, but not for Jua, with females being significantly larger than males in the former host, but not in the latter. Sexual dimorphism in body size has already been reported for several tephritid fly species, with female flies being larger than males (Dodson, 1985; Lemic et al, 2020;Shelly, 2018;Zhou et al, 2020). This size difference between sexes can be attributed to several factors.…”

Seasonal variation in wing size and shape of Drosophila melanogaster reveals rapid adaptation to environmental changes

“…Our results are not consistent with some other studies about the relationship between size and precipitation and humidity. For example, the wing size of Bactrocera tryoni, an Australian endemic horticultural pest species, is also affected by precipitation but shows a negative relationship with precipitation seasonality 86 . Stilwell et al 40 proposed that the latitudinal cline in body size of the seed—feeding beetle Stator limbatus generated by humidity and seasonality then temperature, and the results support humidity for a better candidate to explain the body size clines where body size increased with decreased humidity.…”