Forensic entomologists rely on laboratory growth data to estimate the time of colonization on human re-
mains thus extrapolating a minimum postmortem interval (PMI) if assumptions are satisfied. The flesh fly
Blaesoxipha plinthopyga (Wiedemann) is one species that occurs in casework in Idaho, Texas, and central
California. Because of the few laboratory studies on the development of this fly, the following study was con -
ducted to determine if different substrates impact immature development of the species. In this study, flies
were reared on different substrates that are likely to be encountered at indoor and outdoor scenes (Wet Sand,
Dry Sand, Clothes [Polyester fibers], and Carpet [Polypropylene fibers]) to determine the influence of substrate
on larval, intrapuparial, and total immature development times at 25°C, 50% RH, and 14:10 (L:D) h cycle. The
results revealed that substrate significantly affected minimum immature development times without affecting
the sexes differently; though a female bias in sex ratio was observed consistently. Average minimum larval de-
velopmental times were 160–179 h with a significantly faster development in Carpet than in Clothes. Similarly,
average minimum intrapuparial developmental times were 331–352 h; fastest on Carpet and the slowest in
Dry Sand. For this species, it may be important to consider the substrates encountered at a death scene as
they may affect the development of B. plinthopyga (Wiedemann) in casework by up to 29 h at 25°C and 50%
humidity. These effects will also be important to consider when planning future development studies with the
species.