Anolis occultus

In Puerto Rico, Anolis is represented by 10 separate species. All share adaptations to live primarily arboreal, diurnal lives, while being insectivorous. In comparison to all other Puerto Rican anoles, A. occultus is smaller in size and has a smaller, elongated head. The scales of the head are much smaller in this lizard. The dewlap is also sparsely scaled laterally and tucks under the heavily scaled skin of the throat, which is unique to this species. The mostly closely related lizards by similarity in features include A. fuscoauratus, A. Chloris, and A maculiventris. == Description ==

A. occultus is a slender lizard with a downwards sloping snout and very short limbs. This anole is a small lizard averaging only 1.25 inches in snout to vent length. In contrast to other anole species, both sexes of A. occultus look identical in appearance. The tail of A. occultus is rounded and has small dorsal, overlapping scales. The coloration of the lizard varies and can be shades of white, brown, olive-green, yellowish-green, or dark orange. A. occultus has a mottled, cryptic pattern on its head and body with distinct body banding running from its neck to its vent. The head is grey with sparse dark mottles and the eyelids are a lighter yellow coloration. The flanks are yellowish grey and turn slightly green towards the limbs. The ventral side of the lizard is white besides speckling on the throat and tail. A. occultus has the ability to change color with ease and become slightly darker or lighter in a short period of time. == Habitat and distribution ==

A. occultus is largely an arboreal lizard and is most commonly found in the canopies of the forest. It can also be found in bushes, ferns, and close to the edge of the forest suggesting this species is not restricted to the canopy layer. This lizard is endemic to Puerto Rico and is found throughout the forest of the Cordillera Central mountain range that spans the midline of Puerto Rico from west to east. Home range A. occultus inhabit the peripheral foliage of the mountain rangers and is best defined as a canopy-dwelling species. A. occultus prefers bare twigs and vines in clearings of the canopy. They will not occupy any vegetation in an area with a closed canopy. Twigs are selected carefully as sleeping perches. These lizards show a preference for dense vegetation during the day and no particular preference for dead or living foliage for selection of sleeping perches. A. occultus prefers dead twigs and vines in close proximity to breaks in the forest canopy. A. occultus required a relatively dense bundle of twigs and vines in the canopy with close proximity to an opening where the sky is visible. It seems that the lizards would therefore also occupy the clearing in edges of the forest but this has not been indicated by any research. == Diet ==

A. occultus is primarily insectivorous preying on insects smaller than itself. It has also one of the Anolis species that is nectavorous. This species can perch on twigs and vines and consume nectar from flower buds on the Camasey Almendro plant. The anole is able to stabilize itself on these perches to eat by wrapping its tail around surrounding twigs. ==Ecology and behavior==

Reproduction and social behavior A. occultus is an oviparous lizard meaning it produces young by laying eggs that are hatched later. A. occultus do have a cryptic existence in the foliage because of their long and slender body that allow them to merge easily with the outline of a twig. They forfeit much of this camouflage by exposing themselves at night, but position themselves to minimize this loss of crypsis. Due to this increased vulnerability at night, this anole can reduce the chance of encountering a predator using crypsis and by selecting microhabitats that are less frequently coinhabited by predators. By positioning its body parallel to its perch, these lizards are able to stay very inconspicuous with their mottled patterns. A. occultus sleeps most often on horizontal twigs with its mouth facing the outer edge of the twig. The species also selects twigs that are often too skinny and fragile to support larger predators such as snakes. They have been observed selecting perches higher in the forest canopy at night in order to reduce the probability of predator encounter. Their selection for sleeping sites is strongly based on their diurnal behavior. They tend to occupy sleeping sites that are both higher and less stable than their daytime perches to reduce nocturnal predation. A. occultus select specific sleeping sites and adopt the sleeping position with their head to the outside of the perch to enable approaching predator detection. Furthermore, the tail of A. occultus had been determined to be sensitive to vibration explaining why they wrap their tails around their perches. Besides stabilization, they can detect the vibration of approaching predators through their perch and flee in time. When captured, these lizards release a high-pitched scream which serves to startle an attacking predator. == Conservation ==

A. occultus has been assessed by IUCN as Least Concern because of its widespread observance throughout Puerto Rico. Furthermore, there is a growing need for an accurate assessment of ''A. occultus' '' population status and research into the threats and habitat trends that could put this species in danger. Deforestation has been a serious issue in Puerto Rico's land-use history and information regarding climate change projections and habitat changes need to be explored. For the effective conservation of A. occultus, research on the degree of deforestation and how this is damaging these lizard's habitat is required. In the 1940s only 6% of forest cover remained because agriculture still made up the vast majority of the Puerto Rican economy and deforestation was very prevalent. Few areas of the forests on the island remained unaltered by humans. The market began to shift after the 1940s and agriculture was taken over by industry allowing for regrowth of the forest over many years. 42% of the forest has recovered according to scientists conducting measurements 60 years later. Rural to urban migration and industrialization of a former agricultural economy has resulted in the regeneration of Puerto Rican forests. Rapid regrowth of forests means that the composition of plants differed substantially between different areas. Novel plants contributed to the regrowth of the forests and isolated these lizards into patches of native vegetation. They are very specific in the vegetation they require to be able to select suitable perches and bask in direct sunlight underneath the openings in the canopy. Populations of A. occultus have remained fragmented in these native vegetation patches and have had little recolonization success in the dividing novel vegetation patches in post-agriculture Puerto Rico. ==See also==