It’s sometimes difficult to sex Dendrobates tinctorius frogs. I thought I would share a variety of images of the male and female from our pair to help others see the differences in dimorphism between the sexes of the species.
Note a flash was used for these photos to help illustrate the toe structure of the frogs – this tends to wash out the blue color of the frogs. There is one image of the female below without a flash to provide a reference for their coloration.
The male tends to be leaner and smaller. In general the male’s front toe pads are larger and “heart” shaped. The male also has a more gently sloping back when compared to the female:
The female is more stout and larger. She has a more distinct arch in her back, and generally smaller toe pads on her front feet. Personally the toe pad size is difficult for me to assess. It seems like this female has fairly large toe pads:
Pair side by side
Side by side the differences are more obvious, with the female being significantly larger (she is on the right) and her back arch is more pronounced: