Rhinella “margaritifera” Crested Forest Toad
Some other names for this species:
South American Common Toad
The genus Rhinella was split from Bufo by Frost et al in 2006. Many references still use the long-established name Bufo margaritifer for this species. Still older references use Bufo typhonius, which was a name in use until someone noticed that it already been used for an Old World toad.

Rhinella "margaritifera" is considered a species complex. This means that herpetologists believe that multiple difficult-to-distinguish species are covered by this name, and no researcher has yet done the work required to differentiate them.

Madre Selva Biological Station, Loreto, PeruJanuary 13, 2013
Crested Forest Toad (Rhinella "margaritifera")
These odd little diurnal toads were very common at both of the field stations we stayed at in Peru.

Here is a complete list of the herps I saw in the wild on my 2013 MT Amazon Expeditions trip.

Madre Selva Biological Station, Loreto, PeruJanuary 14, 2013
Crested Forest Toad (Rhinella "margaritifera") Crested Forest Toad (Rhinella "margaritifera")
Some of them are strongly patterned, whereas others are very plain.
Madre Selva Biological Station, Loreto, PeruJanuary 15, 2013
Crested Forest Toad (Rhinella "margaritifera")
Some of them have really perfected the dead-leaf look.
Madre Selva Biological Station, Loreto, PeruJanuary 16, 2013
Crested Forest Toad (Rhinella "margaritifera") Crested Forest Toad (Rhinella "margaritifera")
This mostly-dark-with-yellowish-highlights look was a fairly popular one. Looking at these photos, I'm pretty sure they are of the same individual, though they were taken about four hours apart on one of the forest trails.
Santa Cruz Forest Reserve, Loreto, PeruJanuary 20, 2013
Crested Forest Toad (Rhinella "margaritifera")
Here is a tiny little youngster.
Santa Cruz Forest Reserve, Loreto, PeruJanuary 20, 2013
Crested Forest Toad (Rhinella "margaritifera")
Some individuals have a pronounced vertebral stripe, which further breaks up the animal's outline, making it even harder to recognize when not moving. This is a pretty large adult, with high cranial crests.
Santa Cruz Forest Reserve, Loreto, PeruJanuary 21, 2013
Crested Forest Toad (Rhinella "margaritifera") Crested Forest Toad (Rhinella "margaritifera")
A couple more medium-sized individuals, further displaying the wide assortment of shapes, sizes, and colors currently grouped together in this species complex.
Madre Selva Biological Station, Loreto, PeruJanuary 13, 2014
Crested Forest Toad (Rhinella "margaritifera")
For some reason, these toads were not nearly as common in 2014 as they were in 2013. This is the only one I saw in the first few days, whereas the previous year I saw at least four or five every time I went out hiking.

Here is a complete list of the herps I saw in the wild on my 2014 MT Amazon Expeditions trip.

Madre Selva Biological Station, Loreto, PeruJanuary 15, 2014
Crested Forest Toad (Rhinella "margaritifera")
This one is medium-sized and rather plain. You can see low-rise cranial crests, which might grow much taller as it ages.
Santa Cruz Forest Reserve, Loreto, PeruJanuary 19, 2014
Crested Forest Toad (Rhinella "margaritifera") Crested Forest Toad (Rhinella "margaritifera")
The teeny-tiny forest Rhinella typically have the brightest colors and most dramatic patterns. The very blue toad above was extremely small, less than half an inch long. The one on the lens cap was a little larger, and quite a bit less colorful. I'm not completely certain that these are R. "margaritifera" rather than R. dapsilis, but that's what I'm calling them for now.
Santa Cruz Forest Reserve, Loreto, PeruJanuary 21, 2014
Crested Forest Toad (Rhinella "margaritifera")
A particularly leaf-litter-colored toadlet in the leaf litter.
Madre Selva Biological Station, Loreto, PeruJanuary 31, 2016
Crested Forest Toad (Rhinella "margaritifera")
Another trip to Peru, another batch of toads in this complex. As always, some of these might instead be the difficult-to-distinguish Rhinella dapsilis instead. I think the pronounced crests on this particular toad rule out R. dapsilis.

My Travelogues and Trip Lists page includes a complete list of the herps I saw in the wild on my 2016 MT Amazon Expeditions trip.

Madre Selva Biological Station, Loreto, PeruFebruary 1, 2016
Crested Forest Toad (Rhinella "margaritifera") Crested Forest Toad (Rhinella "margaritifera")
As in previous years, these toads were the most frequently-seen amphibian species on the trip. They came in various color patterns, shapes, and sizes, and were found on the forest floor and on low vegetation.
Madre Selva Biological Station, Loreto, PeruFebruary 2, 2016
Crested Forest Toad (Rhinella "margaritifera") Crested Forest Toad (Rhinella "margaritifera") Crested Forest Toad (Rhinella "margaritifera")
It is hard to find two of these toads that look the same. However, it is not hard to find two of these toads.
Madre Selva Biological Station, Loreto, PeruFebruary 3, 2016
Crested Forest Toad (Rhinella "margaritifera")
Here's a particularly reddish and particularly jowl-encrusted individual.
Madre Selva Biological Station, Loreto, PeruFebruary 3, 2016
Crested Forest Toad (Rhinella "margaritifera") Crested Forest Toad (Rhinella "margaritifera")
This one had a prominent row of spines down the back, and similar (though smaller) rows of spines on the side and on the back legs.
Santa Cruz Forest Reserve, Loreto, PeruFebruary 7, 2016
Crested Forest Toad (Rhinella "margaritifera")
A perfect color match for the decaying leaves on which it was perching.
Santa Cruz Forest Reserve, Loreto, PeruFebruary 8, 2016
Crested Forest Toad (Rhinella "margaritifera") Crested Forest Toad (Rhinella "margaritifera") Crested Forest Toad (Rhinella "margaritifera") Crested Forest Toad (Rhinella "margaritifera")
Here's one last assortment of these ominipresent toads from 2016. Until next time, variable little toads!
Online references: