Sexing Phyllobates

Mick Bajcar

Phyllobates species are notoriously difficult to sex, particularly PP. bicolor and terribilis both of which have females that can call. 

P. bicolor
Photo by Carlos Cabrera

P. terribilis

Chris Miller (via Frognet) has noticed that the cloaca on females of this group is much larger than on the males. This certainly holds true of his P. bicolor (and presumably P. terribilis) and is very visible due to the colour contrast. 

Chris held back 45 P. bicolor tadpoles until the frogs were between 11 and 12 months old and found that, whilst not always true, it was right about 65% of the time. When coupled with fat deposit location and length of body it became accurate 87% of the time. 

Further observations would be welcomed from BDG members on other Phyllobates species. Chris can be contacted at vittatus@hotmail.com

If the photograph of P. terribilis above is yours, please email me so that you can be properly credited.