Forensic aspects of the blow fly Calliphoria vicina

Abstract

Estimations of the post mortem interval form the corner stone of forensic entomology. This is mainly accomplished with the help of larvae of blow flies. However, the wandering stage of 3rd instar larvae and the pupal stage of the important blow fly species Calliphora vicina constitute more than 60% of the total length of the immature stages. These two stages have been very difficult to age until now.
The age of pupae of C. vicina can reliable be estimated without the need for
extensive instrumentation, molecular procedures or the use of colour using a method that is exceptionally fast. The simple dissection of the yellow body allows an estimate of the pupal age with a resolution of 40 °D.
Ageing blow fly pupae based on morphological changes of external characters
of the pharate developing adults is an even simpler method than using the yellow body of the metamorphosing midgut. It is also the simplest method currently available.
The minimum temperature of C. vicina has been for the first time established
under laboratory conditions. It is 11.8ºC.  A new, lower minimum temperature has
been established for C. vicina for survival under diapaus. This is the first study that also includes arrest under diapause.
The first larval instar of C. vicina depends on bacteria as nutrition. Specific
Sphingomonas species are associated with the egg surface and consumed by the first instar larvae.
The nuclei of the salivary glands of C. vicina larvae show sufficient change
during the three days of the wandering stage to allow the ageing of the wandering stage. This is the first investigating in ageing the wandering stage based on morphology.

Date of Award	2015
Original language	English
Awarding Institution	Bangor University
Sponsors	Tetfund, Nigeria
Supervisor	Henk Braig (Supervisor)