This huge toad, Rhinella schneideri – over 20 cm in length – lives in South America: throughout North and Central Argentina, central Bolivia, the Atlantic coast of Brazil, Paraguay and Uruguay (1). It occurs in a wide variety of habitats, from urban areas to the Chaco, Cerrado and Atlantic Forest regions. Fortunately, it is not threatened – listed as being of Least Concern by the IUCN – and is common throughout its range; it is said to adapt well to anthropogenic disturbance, which perhaps explains why it is increasing in numbers, and bodes well for its future. (2)
It is called the Cururu Toad, or the Rococo Toad. Cururu is a river in the Pará state of north-central Brazil; presumably a lot of these toads live there! Rococo is however, a very good alternative name for this toad; the word was derived from the French word “rocaille”, which means pebbles and refers to the stones and shells use to decorate the interiors of caves. The toad looks very much like it is covered with small pebbles.
It is not too fussy about what it eats, as long as it is insect-like and crunchy! Beetles, insect larvae and ants are the mainstay of its diet, but it has even been seen swallowing bees at hives, so bee-keepers consider it a pest! (1)
Don’t try eating this toad! It has poison glands on its back legs, as well as on either side of its head, which can squirt a poison, which causes eyes or mucous membranes to burn painfully. According to one report, ‘a dog that has taken such a toad in its mouth will immediately and yowling release it’! (3) But the interesting thing is that some of the complex organic compounds found in the skin secretions from this toad – at least 10 different compounds have been isolated – are highly active against human cancer cells (4). So who knows, perhaps it contains a cure for cancer?
I took these photographs in March 2012, at a ranch in Corrientes Province, northern Argentina. The frog was obviously feeding on insects attracted to the lights on the buildings at night. I did not notice it at the time, but there is a red and white beetle on the back of the toad. What is it doing? In may be a prey item that just made a lucky escape, or perhaps there is some other sort of relationship occurring? Is it feeding on something on the toad? Who knows? There is also a mosquito feeding on the toad (just behind the right eye), sucking the blood no doubt – see below.
This blog has reminded me once again, that once you start looking closely at an animal, all sorts of interesting – and sometimes unexplained things – pop up!
2) Lucy Aquino, Steffen Reichle, Guarino Colli, Norman Scott, Esteban Lavilla, Jose Langone 2004. Rhinella schneideri. The IUCN Red List of Threatened Species. Version 2014.3. http://www.iucnredlist.org/details/54755/0
4) Cunha-Filho, Geraldino A., et al. (2010). Cytotoxic profile of natural and some modified bufadienolides from toad Rhinella schneideri parotoid gland secretion. Toxicon 56(3): 339-348.
I am a retired entomologist with a background in quarantine pests and invasive invertebrates. I studied zoology at Imperial College (University of London) and did a PhD on the population dynamics of a cereal aphid (Metopolophium dirhodum) in the UK. I spent 5 years with the British Antarctic Survey studing cold hardiness of Antarctic invertebates and 17 years with the Food and Environment Research Agency. My main interests now are natural history, photography, painting and bird watching.