Here are some lovely frogs I photographed at the Universidad de los Andes in Bogotá. Click photos to enlarge (you can do this twice in succession).
Hemiphractus fasciatus (you can see the same frog’s remarkable gape here):
Phyllomedusa venusta. This frog becomes more camouflaged in the second picture, when it’s sitting amidst leaves:
Some of the gorgeous jeweled “harlequin frogs”. Phyllobates bicolor:
Phyllobates terribilis, the famous “golden poison frog”:
This frog is the world’s most poisonous vertebrate. It has in its skin lethal quantities of alkaloid toxins (obtained from its diet) that are used purely as defense against predators. Indigenous peoples make poison darts by heating the frogs in a fire and dipping points into the exudate.
The combination of batrachotoxin and homobatrachotoxin is produced in quantities up to 1900 micrograms per frog, which is at least 20-fold more than other toxic species in the family Dendrobatidae. The range of batrachotoxin-homobatrachotoxin produced by individual frogs was 700-1900 micrograms, with an average of 1100 micrograms per frog. The lethal dose of batrachotoxin-homobatrachotoxin for a 20 gram white laboratory mouse is .05 micrograms when injected subcutaneously. Thus one P. terribilis frog skin contains enough toxin to kill about 22,000 mice. The lethal dose of batrachotoxin for humans is not known but has been estimated at 200 micrograms, with a single frog thus potentially holding enough poison to kill about 10 humans.
Note that this frog is small, too: about 45 mm (ca. 1 and 3/4 inches) long.
Another shot of P. terribilis, showing its inky nose and feet:
These frogs were photographed in the lab of Vicky Flechas at UdlA, who, with her husband Andrew Crawford, hosted me. Many thanks for the hospitality and photography! Here’s Vicky in her meticulously ordered frog lab: