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The upper thermal tolerance for a Texas population of the hairy maggot blow fly Chrysomya rufifacies Macquart (Diptera: Calliphoridae)

NCJ Number
Ecological Entomology Dated: 2020
Date Published

This study investigated the upper thermal tolerance of C. rufifacies exposed to different temperatures (20–45 °C), times (1–6 h), and nutrients (no food or water, water only, or a food-water mixture) for both sexes and two age ranges (young = 6–8 days post pupal emergence; old = 9–11 days post pupal emergence).


The hairy maggot blow fly (Chrysomya rufifacies: Macquart) is an invasive necrophagous fly found throughout the continental United States. Chrysomya rufifacies is of medical/veterinary, forensic, and ecological importance due to its ability to cause myiasis, colonize human remains, and displace native Diptera; however, little is known about their upper thermal tolerance, which could be used to better predict their invasion potential. In the current study, as temperature or duration increased, the probability of knockdown increased (0–100 percent at 20 and 45 °C and from 41 to 75 percent at 1 and 6 h), while the probability of survival decreased (99–2 percent at 20 and 45 °C and from 75 to 28 percent at 1 and 6 h). The availability of nutrients increased thermal tolerance at moderate temperatures (40 and 42 °C). Female flies were more thermally tolerant than males (probability of knockdown = 49 percent vs 58 percent; probability of survival = 58 percent vs 46 percent). Thermal tolerance did not differ by age. These data reveal details about the upper thermal tolerance for a single population of C. rufifacies and suggest that environmental and organismal factors ought to be considered to make meaningful predictions about the invasion potential of C. rufifacies in North America. (publisher abstract modified)

Date Published: January 1, 2020