Males, which are slightly larger than females, possess a conspicuous proboscis, an elongated structure arising from the middle of the snout and about 1–2 cm (0.4–0.8 in) in length; it appears to be used in courtship displays, as is the dewlap that is present in both sexes.

[4] There are multiple colour morphs, with the proboscis ranging from greenish yellow to orange-brown, and variety of patterning over the body, including spots and stripes.

[4] Anolis proboscis bears many resemblances to the Greater Antillean twig anoles, both morphologically, with comparable sexual dimorphism, a slender body, short legs and tail, and in a behavioral sense, residing almost exclusively on narrow surfaces.

[5] One of the most notable features of the species is its proboscis - a pliable, blunt appendage extending beyond the snout approximately 85% of the head length.

[7] Likely, it serves as an intraspecific communication signal, and could also play a role in territorial displays as a way for males to assert dominance over each other or in mate choice.

[1] Despite most sightings of them occurring in areas with severe habitat fragmentation and destruction, it can be concluded that they prefer the deep forest where they are far more difficult to spot.

[6] At night, the lizards roost on small twigs and leaves (less than a centimeter in diameter) between 2.1 and 10 meters off of the ground, which allow them to detect the vibrations of potential predators.

[5] Observations in the Mindo area of Ecuador located the species in apple trees and bamboo plants, as well as in disturbed forest habitats.

[4] The species is currently classified as Endangered due to its possibly restricted distribution in combination with ongoing threats in the form of habitat loss from logging, human settlement, agriculture, and grazing.

[11] However, Anolis proboscis' rarity could be the result of several different factors, including a very niche environment (the canopies of cloud forests), and naturally low populations.

A large array of different insects is preyed on, with the primary sources of food including caterpillars, coleopterans(beetles), hemipterans (bugs), dipterans (flies), and hymenoptera (bees and wasps).

However, this species also eats pseudoscorpions, larvae, millipedes, spiders, and assorted plant material including flower petals, pieces of wood, and seeds.

[13] A. proboscis follows a polygynous mating system, with a wide variety of visual cues and movements involved in the entirety of the process.

[7] Courtship is deemed successful if and when the females runs past the male and continues in the opposite direction which leads to the second stage of mating called chasing.

It involves the male following the female in quick short sprints one to three steps long while frequently bobbing their heads in the same pattern as seen in courtship.

[7] They may also bring their rostral appendages against each other's faces, touching the opposing male with the tip or their snout, or perform slow tail undulations.

[14] During violent male-male interactions, the proboscis remains lifted, and some specimens bear scars, suggesting the appendage can be injured.