Filarial Parasitism in Furcifer viridis from Western Madagascar
Furcifer viridis and the Species Complex
Furcifer viridis belongs to a complex of three closely related species within the genus Furcifer.
These taxa are morphologically similar, with overlapping ranges in western Madagascar, making field identification challenging.
Populations around Morondava are particularly noted for parasitic infections, adding a health dimension to their ecological study.
What Are Filariae?
Filariae are slender parasitic worms (nematodes) of the superfamily Filarioidea.
In reptiles, the most common genus is Foleyella, which infects chameleons and other lizards.
Adults live in subcutaneous tissues or the body cavity, while their offspring (microfilariae) circulate in the blood.
Life Cycle in Chameleons
Adult worms reside in the host's tissues (subcutaneous nodules, intraperitoneal cavity).
Microfilariae are released into the bloodstream.
A mosquito or biting insect vector ingests microfilariae while feeding.
Inside the vector, larvae develop into the infective stage.
During subsequent bites, infective larvae are transmitted to a new reptile host.
The cycle continues, maintaining transmission within sympatric populations.
Clinical Signs in Chameleons
Visible swellings or nodules under the skin, especially in the gular (throat) region.
Subcutaneous infections may be detected during field surveys.
Heavy infections can impair health, though many wild individuals tolerate low parasite loads.
Conservation and Research Notes
The prevalence of filarial infections in F. viridis highlights the importance of vector ecology in western Madagascar.
Understanding parasite cycles is crucial for both wildlife health monitoring and captive husbandry, as imported wild chameleons may carry filariae.