Centrolenidae

People are often surprised when they come to the Amazon that more frogs don't actually look like frogs should look. They are non-descript with dull brown colouring or camouflaged to look like decaying leaves. The classic green 'Kermit the Frog' just doesn't seem to show itself. However, high up in the canopy there is a family of frogs that fit that 'cartoony', bright green, big eyed description. The family is known as Centrolenidae (commonly known as glass frogs).

Centrolenidae are not often found during run of the mill amphibian surveys due to their arboreal nature. They are an excellent indicator species for the health of primary rainforests as they are extremely sensitive to environmental pressures. Their sensitivity stems from the fact that their skin is incredibly thin, so thin that the venter (underside) is in fact transparent. Internal organs can be seen through this window of skin, hence the name glass frog.

In addition to being thin, the skin of the Centrolenidae possesses a unique pigment that reflects the same wavelength of light as chlorophyll found in plant leaves. Undoubtedly this aids camouflage and gives glass frogs their intense green colouration. The green does not stop there though. Bile salts produced by the frog mean even their bones are green.

Although arboreal, Centrolenidae will come down to stream sides in order to mate and deposit eggs. Once fertilised these eggs are laid on leaves or rocks and the young will drop off into the stream on hatching. A recent satellite camp group were fortunate enough to see not one but three Centrolenidae on a night walk last week and two of those were in the act of mating. All are thought to be Cochranella midas species but verification is being sought from the Mueso Ecuatoriano de Ciencias Naturales (MECN) back in Quito. Walks like that really are special and the volunteers are all itching to see more.

Oliver Burdekin, GVI Amazon Field Staff

Centrolenidae