"Amazon Snake Mystery"

Alianza Cristiana, Loreto

Map of the expedition area around Laguna Anatico and Rio Huasaga.
click on map to enlarge and also see true extent of wetlands.

Alianza Cristiana is located along the eastern bank of Laguna Anatico, a very large flooded area surrounded by rainforest, the true extentof which is only visible from the air. We set up our base camp in an elevated building at the southern end of the Achuar village, living in tents erected inside and outside the building, which also had a large open area which was used for dining.

The Nenita from Iquitos, the long boat we had come down from Andoas aboard, and the smaller boats we would use in the tighter watercourses around Laguna Anatico, were moored below out base camp.

The rest of Alianza Cristiana was well laid out, organised and tidy, and centred around a large open area which served as football pitch, town park and helicopter landing zone.


Alianza Cristiana from the air, looking over Laguna Anatico.
Looking back over Laguna Anatico.
Our base and accommodation to the south of Alianza Cristiana
(aerial photographs taken after we had departed)



The Nenita moored alongside our longboat from Andoas and the floating trap. The road into Alianza Cristiana from our base camp house.
Apu Edwing, Achuar village headman of Alianza Cristiana in our tented camp. Director Jon Stephens (Col. Kurtz) reviewing the film schedule in the base camp house.

Our primary host was the Achuar headman Apu Edwing, who did everything in his power to make our stay productive and comfortable.


The trail leading out of the back of Alianza Cristiana passed through interesting microhabitats.. and led to a swampy area, here seen from above.
The swampy area was a possible anaconda haunt. The remains of a possible caiman nest.
We searched the entire swamp with a team of villagers, step by step, without success. The last section was the worst with some sort of underwater biting insect taking pieces out of us.

We searched a number of habitats around Alianza Cristiana, notably the creeks, secondary rainforest and gardens behind the village and a long strip of swampy ground we found a couple of kilometres into the forest. We felt this area held potential for anacondas and caiman but although we found a deserted caiman nest, including the remains of both caiman and turtle egg shells, and what could have been an anaconda trail, we did not find anything else of special herpetological interest, despite trudging slowly and searching thoroughly through the entire length of the swam on two separate occasions. Lutz and I were assisted in this smelly and uncomfortable task by villagers from Alianza Cristiana. We did encounter a large bee-hive in a solitary tree in the centre of the swamp, which we gave a wide birth, and also some ferocious tree ants, but the last stretch of the swamp was the worst as were bitten repeatedly by unseen mouths beneath the water surface.

Another problem was the unseasonal heavy rain which made filming difficult and raised the water-levels and further discoloured the already murky water in the lagoons, swamps and rivers.

Don Lorenzo, the shaman from Alianza Topal,was staying nearby and would be participating in the film when we came to hunt the large anaconda in Panna Cocha.

Lutz and I are both keen anglers and we took the opportunity to fish from the bank or the boats when ever there was a spare hour. Unfortunately we were not very successful, catching only a few small catfish, silver dollars and sardinas, but local fishermen did provide a more sumptuous meal of Black piranha (Serrasalmus rhombeus) and Red-bellied piranha (Pygocentrus nattereri)

The cook on the Nenita prepared a meal of piranha for Lutz and myself and we finished it off with a bowl of roasted ants, a Peruvian rainforest delicacy that tasted a lot better than might be imagined.

Shaman Don Lorenzo in our camp
at Alianza Cristiana.
The cook of the Nenita prepared Lutz and my fish catch, red and black piranha.
A man eating piranha! and to follow, a delicacy of the region,
roasted giant ants, mmmm!

We found most of the reptiles of the expedition around Alianza Cristiana.

Frogs recorded around Alianza Cristiana were the Cane toad (Rhinella marina), Sharp-nosed toad (R.dapsilis) and Crested forest toad (R.margaritifera), the leptodactylid Lowland chirping frog (Leptodactylus andreae), the Ucayali rocket frog (Allobates marchesianus), and the Plain treefrog (Dendropsophus leali).

Marine toad, Rhinella marina
Sharp-nosed toad, Rhinella dapsilis
Crested forest toad, Rhinella margaritifera
Lowland chirping frog, Leptodactylus andreae
Ucayali rocket frog, Allophryne marchesianus
Plain treefrog, Dendropsophus leali

The lizards included two geckos, the gekkonid Cosmopolitan house gecko (Hemidactylus mabouia) and the sphaerodactylid Common bent-toed gecko (Gonatodes humeralis), one skink, the Black-spotted skink (Mabuya nigropunctata), one microteiid, the Slender eyed lizard (Prionodactylus manicatus bolivianus) and two teiids, the Western forest whiptail (Kentropyx pelviceps) and Upper Amazon savanna whiptail (K.altamazonica). There were also two iguanians, the Slender anole (Anolis fuscoauratus fuscoauratus), from the Polychrotidae, and the Olive tree-runner (Plica umbra ochrocollaris), from the Tropiduridae.

Cosmopolitan gecko, Hemidactylus mabouia
Common bent-toed gecko, Gonatodes humeralis (male)
Black-spotted skink, Mabuya nigropunctata
Slender eyed lizard, Prionodactylus manicatus bolivianus
Western forest whiptail lizard, Kentropyx pelviceps
Upper Amazon savanna whiptail lizard, Kentropyx altamazonica
Slender anole, Anolis fuscoauratus fuscoauratus
Olive tree-runner, Plica umbra ochrocollaris


Snakes included several colubrid species, ie. two Amazon banded calico snakes (Oxyrhopus petola digitalis), a juvenile Amazon scarlet snake (Pseudoboa coronata) and a Blunt-headed treesnake (Imantodes cenchoa).


Amazon banded calico snake, Oxyrhopus petola digitalis
Amazon scarlet snake, Pseudoboa coronata
Blunt-headed treesnake, Imantodes cenchoa


We found two Amazonian rainbow boas (Epicrates cenchria*) near Alianza Cristiana, the only boas we found. Both were found close to human habitations and being feared by the villagers would probably have been killed if we were not present.

* The genus Epicrates contained nine species, eight of which were confined to the Caribbean. The sole mainland Central and South American species was Epicrates cenchria, the rainbow boa, with nine subspecies from Costa Rica to Argentina. The brightly patterned specimens we found in Loreto belonged to the Peruvian subspecies, E.c.gaigei, which was very similar in appearance to the much more familiar Brazilian rainbow boa, E.c.cenchria. However, all this has now changed with the publication of an important monograph (below). Today the nine taxa have been reduced in number to five, all of which have been elevated to specific status, with no subspecies recognised. Hardly surprisingly E.c.gaigei has been synonymised within the re-defined species E.cenchria, in the Amazon Bazin. The other four species are: E.maurus, in the north; E.alvarezi, to the southwest; E.crassus, in the south-centre, and E.assisi, in the east.

Passos, P. & R.Fernandes 2008 Revision of the Epicrates cenchria complex (Serpentes: Boidae). Herpetological Monographs 22:1-30.

Amazonian rainbow boas, Epicrates cenchria


Lutz and Mark with two
Amazonian rainbow boas, Epicrates cenchria

The bird-eating spider that exited the whole the boa went into!


A large bird-eating spider, Theraphosa blondi or Pamphobetus sp. ?


Lutz released the second rainbow boa down a hole in the rainforest, but the hole was already occupied by a large bird-eating spider which scuttled out as the boa dived in. I think this was the largest mygalomorph spider I have ever seen in the wild and closely resembled the Goliath bird-eating spider (Theraphosa blondi). However that species is northern South American, from Venezuela, Brazil and the Guianas, so if this is a correct identification if would be the first specimen recorded from Peru. It may also belong the a related genus of large bird-eating spiders, Pamphobetus, which does occur in the Andean foothills of western Amazonia. In the absence of collection permits the spider was also released.

The only venomous snake was also found at Alianza Cristiana, a specimen of Common lancehead (Bothrops atrox) found near a house on the periphery of the village. A venomous green pitviper was reported on the bank of the Laguna Anatico but we failed to find it which was a shame because it was almost certainly the attractive but extremely venomous Western two-striped forest-pitviper (Bothriopsis bilineata smaragdina).

Common lancehead, Bothrops atrox