Aerial roots on steroids at Parque Nacional Volcán Arenal (Costa Rica)

[Gunnar Hillert]

I was hiking 2 days ago at Parque Nacional Volcán Arenal in Costa Rica. The trail started slow but further along, things became truly impressive. I encountered several species of palms that I will be trying to narrow down a bit over the next few days (My ability to identify palms in the field is sadly still severely lacking). Nonetheless, I saw a ton of specimens of a palm with aerial roots that just knocked my socks off. Based on some cursory research this may be Chamaedorea tepejilote (??, PLEASE correct if I am off!!) but I have not seen any comparable pictures on Google with such an assortment of amazing aerial root. Is this just caused by the extreme levels of humidity? I actual have one Chamaedorea tepejilote in my garden but it sadly does not have anything like this. Many of the specimens had this type of aerial roots.  4 examples with picture follow below.

In this palm, the main tap root does not even touch the soil. 

[Gunnar Hillert]

Example palm 2:

[Gunnar Hillert]

Example palm 3:

[Gunnar Hillert]

Example palm 4. This one is particularly interesting as the trunk just creeps horizontally along the soil and then takes a 90 degree vertical turn with aerial roots (can you call them stilt roots?) forming at the turn point.

[awkonradi]

Very interesting.  Morphology similar to a mangrove, but not in a tidal zone.  I speculate these "flying buttress" roots stabilize a skinny palm growing upwards to the canopy and sunlight.  Perhaps a wiser PalmTalker than me will comment.

[awkonradi]

I speculate the bent palm fell over, and then established some new roots, and then turned upwards again.

[Jonathan]

19 hours ago, Gunnar Hillert said:

Example palm 2:

Great stuff Gunnar, those are fascinating pictures. I've never seen a palm with aerial roots for the full height of the trunk before, very strange. It's reasonably easy to understand why they would be useful at the base as stilt roots to stabilise and add mass to the root system...but up the trunk? Does it help,them scramble through the canopy maybe? Cool, thanks for sharing!

[Gunnar Hillert]

Is it a different form? Here is an example (same/similar species) from the Caribbean side (Punta Cocles, Jaguar Rescue Center) where the areal roots go ALL the way to the top. This example is at sea level. I am just a bit baffled that this is so common around here but, yet, I did not see much on Google on this ¯\_(ツ)_/¯

[Jonathan]

Very strange indeed, makes me wonder if there's a genetic predisposition in that particular population. The tropics never cease to come up with novel life forms! 

I pulled a leaf base off from just under the crown of a C elegans a few days ago and was surprised to see a cluster of roots growing in there, yet none down the rest of the trunk. I guess it's just a nice humid place to grow some roots, although hard to see the advantage to the palm.