Estudo da dispersão larval radial pós-alimentar em Chrysomya megacephala (Fabricius) (Diptera, Calliphoridae)

Abstract

ABSTRACT. Study of postfeeding larval radial dispersal in Chrysomya megacephala (Fabricius) (Diptera, Calliphoridae). Blowflies utilize discrete and ephemeral sites for breeding and larval nutrition. After the exhaustion of food, the larvae begin dispersing to search for sites to pupate or to additional food source, process referred as postfeeding larval dispersal. Some of the most important aspects of this process were investigated in Chrysomya megacephala, utilizing a circular arena to permit the radial dispersion of larvae from the center. To determinate the localization of each pupa, the arena was split in 72 equal sectors from the center. For each pupa, distance from the center of arena, weight and depth were determined. Statistical tests were performed to verify the relation among weight, depth and distance of burying for pupation. It was verified that the larvae that disperse farther are those with higher weights. The majority of individuals reached the depth of burying for pupation between 7 and 18 cm. The study of this process of dispersion can be utilized in the estimation of postmortem interval (PMI) for human corpses in medico-criminal investigations.

A review of postfeeding larval dispersal in blowflies: implications for forensic entomology

“…Other studies have described general aspects of larval dispersal in a circular arena and have confirmed results obtained using troughs (Gomes et al 2002(Gomes et al , 2003. The U circular arena arrangement used by Gomes et al (2002Gomes et al ( , 2003 (Fig.…”

“…The U circular arena arrangement used by Gomes et al (2002Gomes et al ( , 2003 (Fig. 1) provides a closer simulation of the natural conditions that the larvae face when they abandon their feeding substrate in search of a site to pupate (Ullyett 1950).…”

Rearing five species of Diptera (Calliphoridae) of forensic importance in Colombia in semicontrolled field conditions

“…L. eximia seems to be very sensitive to stress and in the present study this could have been caused by the lack of a successful migration event and posterior burial. This species, as others of the subfamily Calliphorinae (Greenberg, 1990), has been characterized by displaying strong intentions to escape from sample jars, showing their need for migration away from the food source and thus explaining the mass movement of larvae during the postfeeding stage in the jars (Anderson, 2000;Gomes et al, 2003;Gomes & Zuben, 2004). The absence of this migration requirement given by the small space, and the absence of burial given by the kind of substrate to pupate (sawdust instead sand), could explain the failure to reach pupation and the adult stage.…”

Dispersão larval pós-alimentar de Lucilia sericata (Diptera, Calliphoridae) em condições de laboratório

“…(GOMES & VON ZUBEN, 2004a). Trabalhos realizados com outros dípteros, referentes a propagação em arena circular, utilizando serragem como substrato de pupariação (GOMES et al, 2003;GOMES & VON ZUBEN, 2006), demonstraram grande variação quanto à profundidade média de pupariação. Segundo GOMES & VON ZUBEN (2004b), as larvas tendem a se aprofundar mais ou menos de acordo com a temperatura à qual estão submetidas, havendo um maior enterramento na tentativa de escapar das temperaturas mais baixas.…”