Stories
We found (and yelled at) a crazy tentacled caterpillar
On my recent travels through the Peruvian Amazon, I came upon the craziest caterpillar that I have ever seen and subsequently yelled at it for hours. Why did I yell at it? Well, its strange behavior towards sound was why I noticed it in the first place. I had just climbed to the top of a canopy tower overlooking the rainforest when I called to my group below me – suddenly a flash of movement at eye-level caught my attention.
Hear about my caterpillar adventures below. And to check out more otherworldly jungle creatures — and even help with scientific discovery — join in our Wired Amazon project!
On a nearby tree branch hung a caterpillar with four strange tentacle-like appendages protruding from its abdomen. I might never have noticed this small brown insect had it not been for its unusual movement: noises would cause it to fire its tentacles in randomized directions, then slowly twirl back into a spring-like “ready” position to await its next alarm. This reaction to noise was so peculiar that once my group joined me around the creature, we proceeded to take turns yelling at it and filming its contorting reactions for over an hour.
After a little research, I found that this caterpillar is in the moth family Geometridae and is in the genus Nematocampa. Also referred to as ‘horned-spanworms’ or ‘filament bearers’, these peculiar caterpillars can be found in North America and the Neotropics.

David Wagner, in his field guide ‘Caterpillars of Eastern North America,’ notes:
“It is difficult to imagine what the [Nematocampa] larva is mimicking, but the overall effect is not unlike a fallen brown flower with exerted stamens. Alarmed caterpillars shunt hemolymph into filaments, enlarging them by as much as twice their resting length.” [1]
What Wagner seems to be proposing is that the larva movement is similar to the way flowers or other plant matter move in the wind: the behavior more effectively blends the caterpillar into its surroundings.
Other potential purposes this behavior may serve to include:
- The tentacles extend when the caterpillar is alarmed so that an attacking predator (such as a bird) has a higher probability of snagging a tentacle, as opposed to the main body, so that the caterpillar may drop away and escape with its life (similar to how some lizards are able to lose their tails).
- The setae, or “hairs,” located at the tip of a long tentacle could be highly sensitive vibration detectors that are able to sense predacious birds or insects that make nearby sounds [2].

What do you think? Screaming at caterpillars doesn’t fall into most people’s job descriptions. But that’s exactly what I found myself doing a couple of weeks ago in the Peruvian Amazon, all to bring the story of this bizarre organism to you! Leave a comment below and let us know how you feel about this peculiar caterpillar found in Tambopata, Peru.
To discover these fascinating caterpillars, along with dozens of other incredible species, book your dream trip to the Amazon today!
By Aaron Pomerantz, Entomologist
You can follow me on Twitter @AaronPomerantz
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Fantastic to be deep in the forest surrounded by incredible wildlife with our amazing guide Juan Carlos Yatto, who really knew his stuff! Also his photography skills meant that we could share our experience even better through his telescope using our phone cameras! We learned so much!! He went to extra lengths to find butterflies and moths for us along with so many different birds and monkeys. This was a travel highlight for us as experienced wildlife travellers. We loved our spacious room with no windows and open to more wildlife visitors but after 5 nights the bed could have been a little more comfortable. Luckily we had a second bed to use. Otherwise it was fantastic with hot water showers and fresh drinking water all the time. We were amazed at the variety of food on offer for breakfast, lunch and dinner and couldn’t believe they could have such a wonderful food offering in such a remote location. Even the wine and cocktails were great. I highly recommend spending the extra money and time getting to this location. We stayed at another lodge later which was closer to Puerto Maldonado and there was far less wildlife. Read all
Ederson made the stay at the lodge amazing. I have had many guides around the world and Ederson may be the best I have had across 50 countries. The lodge itself is nice, and has electricity. Food is good, and you really feel immersed in the amazon staying there. Its great that a portion of the money goes back to conservation and research. Noteworthy details: Ederson, the "commander" is the best guide! Read all
Through a travel agency in Lima we booked a 4day/3-night stay at Refugio Amazonas. We were looking for a lodge that was far away from Puerto Maldonado but didn't require almost a day to get there (like TRC), with extensive walking trails and with the principal jungle highlights nearby. We were not disappointed. As we later learned, this is probably the best lodge in the region! Well run, quiet, excellent food, beautifully located in the middle of the forest, everything was "right". Surprisingly there were few mosquitos or bugs. Emperatriz (MP as some call her), our guide, has a keen eye and took us on some unforgettable walks and boat rides, both day and night. The birds at the clay lick were fantastic. The lodge also had evening lectures by young researchers as well as special activities such as collecting night moths and setting a trap camera. We later received videos and photo's of what was found (including a puma!). I can recommend this lodge without reservation. Read all
Abbiamo scelto il Tambopata Research Center perché il nostro obbiettivo era di poter vedere le are da vicino. Ci siamo stati ad inizio dicembre scorso, l'inizio della stagione delle piogge, perciò abbiamo scelto di restare 5 notti/6 giorni, abbiamo messo in conto di perdere delle giornate a causa della pioggia e per la lontananza da Puerto Maldonado, per nostra fortuna durante il nostro soggiorno ha piovuto solo il giorno di partenza proprio quando arrivavamo in aeroporto. Non c'é stato un giorno che non ne abbiamo visto: are di diverse specie e colori e molti altri uccelli e primati, spettacolare l'incontro a pochi centimetri con un formichiere bianco, ma non il giaguaro. Consigliamo di pernottatre almeno 3 notti, il viaggio é molto lungo. Noi eravamo all'aeroporto di Lima già alle 8:00 di mattina e tra un volo in ritardo, uno spostamento in bus di ca. 45 minuti per arrivare al fiume, ed un trasferimento in barca veloce, siamo arrivati al lodge verso le 16:30. All'aeroporto ci ha accolto la nostra guida privata Alfred, che ci ha seguito per tutto il soggiorno, di giorno in giorno abbiamo deciso le escursioni da fare, ed Alfred si é rivelato essere una super guida, un occhio di falco per scoprire anche il più piccolo uccellino, con pazienza é riuscito a farci camminare chilometri nella giungla, ci ha spiegato molto sulla flora e fauna. Bravissimo a far video e foto con i nostri telefoni col suo binocolo e cavalletto che si portava sempre appresso, queste foto sono dei magnifici ricordi. TRC non é un hotel, é un centro di ricerca per le are, in mezzo ad una foresta ed a ore dal primo centro abitato, perciò non avevamo delle grandi aspettative ne sul cibo ne sull'alloggio Read all
This place is a treat!! Incredible flora & fauna, food and service - the staff is quite attentive. Interesting research, with lots of potential. Visiting the Peruvian Amazon Rainforest is a must do! Read all
We had the most amazing time EVER at Refugio Amazonas, and I am so very glad I booked our stay here. Honestly, this is to date probably the best travel experience we have ever had and I will never forget our time in the Amazon here. First of all, the lodge is beautiful. Our room was lovely. The beds were comfy. The bathrooms are large. It is incredible waking up to the sounds of the jungle and falling asleep to the insects at night. We did have some insects in our room, and a rodent, and even a tarantula (non poisonous)! But it was part of the experience. The food was great and they prioritize native and local ingredients. My partner and I are both vegan and they took SUCH good care of us. The food was delicious, and we had ample vegan options every meal. Everything from the first email contacts with Katia to the transfers to the first night info session to the activities-- which I will get to in a second-- was incredible. It is a bit pricey, but everything is included and there is nothing you need to worry about, and it was so worth it. OK now for the best part-- the activities. Holy wow. First of all, we had the best guide EVER-- Juan Carlos. He was amazing. He is a bird expert, knows so much about the animals who live in the rainforest, the insects, the trees, the plant life, it was incredible. He also so clearly cared that everyone in our group had an amazing time. He took so many pictures for us, pointed out so many animals for us, and made sure we all enjoyed every moment. I can’t thank him enough because it made our time here so very special. We went on many activities that were amazing, and we saw so many animals— capybaras, howler monkeys, capuchin monkeys, so many incredible insects, frogs, tarantulas, so many many birds and butterflies. Every activity was amazing but the highlights were the macaw clay lick and the canopy tower. And we were super impressed and happy to hear about their commitment to conservation, protecting the animals, and supporting the native community nearby. There is so much I could say about our stay here but I would recommend a 3 night stay over 2 nights (so you can do more activities), and make sure you read the guides they send via email before you come so you pack correctly and know what to expect and bring--the guide includes everything so that there are no surprises, and we knew exactly what to expect, although our stay exceeded our expectations! I highly, highly recommend staying here, it was magical, it was a once in a life time adventure, and I will never forget it. I also want to shout out the manager of the lodge, I forgot her name, but she was incredible, as well as the service staff at meal times, who were so kind and helpful to point out what was vegan all of the time. I truly hope we can come back some day!! Read all
The lodge was kept very clean, and the staff paid close att to people's needs. It was very easy find activities and the guides were excellent with a genuine intended approach towards sustainability and environment longevity. Read all
A superb stay in a top class Lodge which gave a wonderful insight into the Amazon wildlife. Our guide was Juan Carlos who has incredible knowledge and a lovely sense of humour. The staff in the lodge were so friendly and the meals provided were something to look forward to. A wonderful experience! Read all
I traveled with my mom, who is elderly, and we were a little scared but decided to go for it. Upon arrival, our guide, Christian Herrera, was waiting for us. He was very friendly and had extensive knowledge of the area. The lodge is wonderful, 100% connected to nature. The food is delicious, and everything there is to do near the lodge is incredible. I highly recommend going to the tower at sunset and the macaw clay lick at dawn. Thank you guys for everything, the stay was a dream. Read all
This place totally stole the show! We came to Peru for Machu Picchu, but I think it’s safe to say Refugio Amazonas became the absolute highlight of our trip.It manages to be as luxurious as a stay in the Amazon can be without feeling like too much hand-holding. The rooms don't have windows, which lets you be super close to nature. Sure, that means moths, but it also means drifting off to the peaceful sound of cicadas and waking up to howler monkeys. I honestly can't remember the last time I had such deep, peaceful sleep.The food is another major plus; it's exceptionally fresh, especially considering it’s a buffet. You should absolutely check out their menu, too—it’s one of the most thoughtful and best-designed ones I’ve ever seen. Kevin hosted us at dinner most nights, and he was such great company and so mindful of my wife's dietary restrictions. It really adds to the experience when you feel that people genuinely care.We also took advantage of the exceptional massage here. After a long trip, a massage by Kelly was exactly what the doctor ordered.But the real star of the show is the activities and the guides. We got incredibly lucky with the very best: Juan Carlos. He was funny, great company, and extraordinarily knowledgeable. All the guides at Refugio Amazonas understand that it's not about just ticking a box but about living the experience. That’s why you might take 30 minutes longer to complete a hike—because you decided to spend some time watching Tamarins playing with each other. Jonathan was another guide we had a wonderful, very knowledgeable, and fun time with. We honestly just didn't want to leave and wish we could have stayed longer. Read all
We just finished three weeks in Peru and without a doubt Refugio Amazonas lodge was a real highlight of the trip. You need to know there is NO AC but honestly you don't need it at night in October, There's a ceiling fan and the bed was super comfortable with netting and additional fan within the bed area. The sounds of the jungle at night and Howler monkeys in the morning was great experience. The staff was excellent with a special mention for Paul our guide. He is an excellent Birder as well and can't thank him enough for over 110 new bird species during our four days there. The early morning Macaw clay lick experience with the boat ride in the dark was very cool. The buffet style meals were ok, make sure you bring shoes for mud and extra to walk around with in the lodge. Refugio provides boots for water on trails. See photos Read all
This place totally stole the show! We came to Peru for Machu Picchu, but I think it’s safe to say Refugio Amazonas became the absolute highlight of our trip.It manages to be as luxurious as a stay in the Amazon can be without feeling like too much hand-holding. The rooms don't have windows, which lets you be super close to nature. Sure, that means moths, but it also means drifting off to the peaceful sound of cicadas and waking up to howler monkeys. I honestly can't remember the last time I had such deep, peaceful sleep.The food is another major plus; it's exceptionally fresh, especially considering it’s a buffet. You should absolutely check out their menu, too—it’s one of the most thoughtful and best-designed ones I’ve ever seen. Kevin hosted us at dinner most nights, and he was such great company and so mindful of my wife's dietary restrictions. It really adds to the experience when you feel that people genuinely care.We also took advantage of the exceptional massage here. After a long trip, a massage by Kelly was exactly what the doctor ordered.But the real star of the show is the activities and the guides. We got incredibly lucky with the very best: Juan Carlos. He was funny, great company, and extraordinarily knowledgeable. All the guides at Refugio Amazonas understand that it's not about just ticking a box but about living the experience. That’s why you might take 30 minutes longer to complete a hike—because you decided to spend some time watching Tamarins playing with each other. Jonathan was another guide we had a wonderful, very knowledgeable, and fun time with. We honestly just didn't want to leave and wish we could have stayed longer. Nearby activities: We did the macaw clay lick, mammal clay lick, night walk, medicinal trail, canopy walk twice, and the oxbow lake. Safety: As safe as you can be in the Amazon rainforest Food & drinks: Excellent varied buffet lunches and dinners every day. Read all
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