Analysis on fly artifacts produced by forensically important blowfly, Chrysomya
megacephala (Fabricius) (Diptera:Calliphoridae), revealed several unique patterns. They can be
divided into fecal spots, regurgitation spots and swiping stains. The characteristics of fecal spots
are round with three distinct levels of pigmentation; creamy, brownish and darkly pigmented.
Matrix of the spots appears cloudy. The round spots are symmetrical and non-symmetrical,
delineated by irregular and darker perimeter which only visible in fairly colored fecal spots.
Diameter of these artifacts ranged from 0.5 mm to 4 mm. Vomit or regurgitation spots are
determined by the presence of craters due to sucking activity of blowflies and surrounded by
thickly raised and darker colored perimeter. The size of these specks ranged from 1 mm to 2 mm.
Matrix of the spots displays irregular surface and reflective under auxiliary microscope light.
Swiping stains due to defecation by flies consists of two distinguishable segments, the body and
tail. It can be seen as a tear drop-like, sperm-like, snake-like and irregular tadpole-like stain. The
direction of body and tail is inconsistent and length ranged between 4.8 mm to 9.2 mm. A finding
that should be highlighted in this observation is the presence of crater on tadpole-like swiping
stain which is apparent by its raised border characteristic and reflective under auxiliary microscope
light. The directionality of this darkly brown stain is random. This unique mix of regurgitation
and swiping stain has never been reported before. Highlighting the features of artifacts produced
by flies would hopefully add our understanding in differentiating them from blood spatters
produced from victims at crime scenes.