The possible dissimilitudes relating to the duration of the egg incubation period and larval stage of Cochliomyia macellaria (Fab., 1775) from offsprings of females from larvae with and without pigmentation on Malpighi tubules, morphotype 1 and 2, respectively, was questioned. The experiment was conducted in climatized chamber regulated at 30ºC, 65±10% RH and 14 hour photophase. No significant difference was observed on average duration of first and second larval instars berween the two morphotypes, taking into account not only the conventional interpretation for the reading of different development phases of the larval stages (morphotype 1:11.0 and 11.9 hours and morphotype 2:11.7 and 12.7 hours for first and second instars, respectively), but also the reading made through the interpretation preconized by Snodgrass & Hinton (morphotype 1:10.3 and 9.6 hours and morphotype 2:9.8 and 10.8 hours for the first and second instars, respectively). The incubation period was significantly longer for eggs posited by females from non-pigmented larvae.
Secondary screwworm; blow fly; ontogeny; carrion-eating dipterous; necrophagous flies