Ceratophora tennentii, Tennent's Leaf-nosed Lizard, is found only in the Knuckles Hills region of central Sri Lanka, an area characterized by tropical moist montane forest. The range encompasses approximately 175 square kilometers. (Manamendra-Arachchi and Liyanage, 1994; Bahir and Surasinghe, 2005; Manamendra-Arachchi and Liyanage, 1994; "Tennent’s leaf-nosed lizard (Ceratophora tennentii)", 2003)
Ceratophora tennentii is found in the moist tropical montane cloud forests of Sri Lanka's 'wet zone'. This mountainous region exists at an elevation of 700 to 1,200 m above sea level and receives more than 2,000 mm of precipitation each year. The Leaf-nose lizard is an arboreal species found most often on the trunks of mossy trees, but also on low bushes, cardamom plants, and on lianas (Somaweera and Somaweera 2009). (Bahir and Surasinghe, 2005; Somaweera and Somaweera, 2009)
Tennent's Leaf-nosed Lizards are small reptiles named after the conspicuous leaf-shaped projection located at the end of their rostrum. This ornamentation is fleshy, covered in scales and granules, and tipped with a bluntly conical scale. The shape is unique to the species as it is laterally compressed and elliptical from a lateral view. The appendage is present in juveniles and monomorphic in adults, though somewhat smaller in females. The function of this appendage is unknown, however field observations suggest it is not obviously used in breeding or threat display (Pethiyagoda and Manamendra-Arachchi 1998). Some researchers have hypothesized that the appendage serves to increase crypsis by breaking up the lizards' outline (Johnston et al. 2013).
Average snout to vent length is 55-70 mm, and tail length is 130-145 mm (Somaweera and Somaweera 2009). Adults typically have a short and think tongue, a nuchal crest that is poorly defined or lacking completely, and no gular fold. The nostrils are rounded or oval shaped and oriented anterolaterally. The digits and claws are laterally compressed, and the claws are slightly curved and pointed (Pethiyagoda and Manamendra-Arachchi 1998).
Adults are typically reddish brown to olive green on the dorsum and sides (Pethiyagoda and Manamendra-Arachchi 1998). Lateral scales are large, irregular, and often more green (Somaweera and Somaweera 2009). Black markings are found on the area around the eyes and sides of the neck. There are about 10 broad, dark brown bands on the tail with narrow lighter areas in between. The venter is whitish (Pethiyagoda and Manamendra-Arachchi 1998). (Johnston, et al., 2013; Pethiyagoda and Manamendra-Arachchi, 1998; Somaweera and Somaweera, 2009; "Tennent’s leaf-nosed lizard (Ceratophora tennentii)", 2003)
As with all squamates, fertilization is internal, the male possessing a dual intromittent organ called the hemipenes. This species is oviparous and lays shelled amniotic eggs. Hatchlings resemble the parents, though with much smaller ornamentation. (Pianka and Vitt, 2003; "Tennent’s leaf-nosed lizard (Ceratophora tennentii)", 2003)
Tennent's Leaf-nosed Lizards are oviparous, and females lay 2-4 eggs at a time (Somaweera and Somaweera 2009). Males expand a small erectile nuchal crest on the back of the neck while displaying (Hutchins 2003). Little else is known about the reproductive biology of this species. (Hutchins, 2003; Somaweera and Somaweera, 2009)
Females provision the eggs (yolk), but probably deposit and then abandon their eggs (as with most agamid lizards) and there is likely no parental care of hatched young. (Pianka and Vitt, 2003)
No data could be found on lifespan and longevity of the Leaf-nosed lizard.
Tennent's Leaf-nosed Lizards are slow-moving and arboreal (Johnston et al. 2013). They prefer to spend the majority of their time on low branches of trees utilizing the sit-and-wait predatory strategy (Hutchins 2003). Juveniles are largely terrestrial (Somaweera and Somaweera 2009).
This species is known operate at relatively low body temperatures close to air temperature. Some thermoregulation is managed by basking, often in dappled sunlight. Due to the closed canopy nature of the forest and frequent cloud cover, seeking out open sunlight patches may be too ecologically costly for these organisms (de Silva et al. 2005).
Within the Agamidae family, males are generally known to be territorial and show territorial behaviors more often than females and juveniles. Ceratophora tennentii males have been reported performing two of these territorial behaviors: head bob and body-lift. The head bob behavior is performed by relatively rapid up and down movements of the head and neck only. The body-lift behavior consists of using all four limbs to push the body off the surface immediately followed by descent (Bandara 2012).
Although this species is slow-moving, males may actively attack other rival males. When disturbed, they will occasionally open their mouth wide to display the bright orange lining of their oral cavity (Somaweera and Somaweera 2009). (Bandara, 2012; Hutchins, 2003; Johnston, et al., 2013; Somaweera and Somaweera, 2009; de Silva, et al., 2005)
The home range of this species has not been reported to date.
These Leaf-nosed lizards rely mostly on visual communication within the species. Males exhibit territorial behaviors such as a head-bob and body-lift (Bandara 2012). Any use of other senses has not been reported.
When disturbed, members of this species will often open their mouths wide to display the bright orange lining of their oral cavity (Somaweera and Somaweera 2009). (Bandara, 2012; Somaweera and Somaweera, 2009)
Tennent's Leaf-nosed Lizards are sit-and-wait ambush predators that feed on insects, caterpillars, and earthworms (Somaweera and Somaweera 2009). Although they most often feed while in trees, they will occasionally jump to the ground in pursuit of prey (Hutchins 2003). (Hutchins, 2003; Somaweera and Somaweera, 2009; "Tennent’s leaf-nosed lizard (Ceratophora tennentii)", 2003)
This slow-moving species appears to rely largely on camouflage to evade predators (Hutchins 2003). (Hutchins, 2003)
Tennent's Leaf-nosed Lizard impacts the ecosystem of the Knuckles range by capturing and consuming insects, caterpillars, earthworms, and other invertebrates (Somaweera and Somaweera 2009). (Somaweera and Somaweera, 2009)
The Leaf-nosed lizard has no known economic significance to humans, other than acting as a minor predator on insects (Hutchins 2003). (Hutchins, 2003)
This species has no harmful impacts on humans. ("Family Agamidae", 2013)
Ceratophora tennentii is listed as Endangered on the IUCN Red List. The most prevalent cause of population decrease is destruction of habitat. Approximately five percent of the original extent of Sri Lanka's wet zone rainforest survives and much of this is severely fragmented. C. tennentii is restricted to the Knuckles mountain range, most of which currently has no protection status and is not subject to conservation management (Bahir and Surasinghe 2005). In the 1960s, the vast majority of the remaining forest in the Knuckles Hills was underplanted with cardamom. This process has left the canopy in good condition, but the regeneration of natural forest has been almost completely inhibited (Manamendra-Arachchi and Liyanage 1994). (Bahir and Surasinghe, 2005; "Ceratophora tennentii", 1996; Manamendra-Arachchi and Liyanage, 1994)
Three of the five species in the genus Ceratophora display horn-like rostral appendages, however these appendages are radically different from one another. Combined morphological, allometric, and phylogenetic evidence suggests that these horn structures evolved independently three times within the genus (Johnston et al. 2013; Schulte et al. 2002). (Johnston, et al., 2013; Schulte, et al., 2002)
Rachel Emory (author), Michigan State University, James Harding (editor), Michigan State University, Tanya Dewey (editor), University of Michigan-Ann Arbor.
Referring to an animal that lives in trees; tree-climbing.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
an animal that mainly eats meat
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature
An animal that eats mainly insects or spiders.
animals that live only on an island or set of islands.
eats mollusks, members of Phylum Mollusca
the area in which the animal is naturally found, the region in which it is endemic.
found in the oriental region of the world. In other words, India and southeast Asia.
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
rainforests, both temperate and tropical, are dominated by trees often forming a closed canopy with little light reaching the ground. Epiphytes and climbing plants are also abundant. Precipitation is typically not limiting, but may be somewhat seasonal.
reproduction that includes combining the genetic contribution of two individuals, a male and a female
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
uses sight to communicate
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