A scary finding.These larvae were found near the tail head of a stray dog. The dog is approximately 2 years-old but no other history was available. The larvae were submitted to the diagnostic lab for identification.  Image 1: Gross specimen. Lateral view (16 mm in length)  Image 2: Posterior end of larva showing spiracular plate. Diagnosis:
Lucilia sericata third instar. Also called common green bottle fly. Found throughout the world, but is more specifically described as having a Holarctic (Northern Hemisphere) distribution, being widely distributed throughout the United States and southern Canada. The larvae feed exclusively on carrion and excrement where they develop after hatching from eggs. The larval stages can cause myasis in animals and humans. Larvae: All stages are smooth, conical-shaped, and have a complete peritreme on the posterior spiracles. The larvae are white or yellowish through all three instars of development and reach a maximum of 12–18 mm before pupation. Adults: The adults are usually a metallic green color and can also have a copper green hue. The back is hairy and the overall diameter is about 8–10 mm.
Posterior segment with two spiracles (three slits per spiracle = third instar), distance between each papilla (P) similar to distance between P1 and P2. Complete peritreme (black arrow) and central button (blue arrow). |