Plumed basilisk

Plumed basilisk
Male, Alajuela Province, Costa Rica
Female plumed basilisk
Conservation status
Least Concern  (IUCN 3.1)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Squamata
Suborder:	Iguania
Family:	Corytophanidae
Genus:	Basiliscus
Species:	B. plumifrons
Binomial name
Basiliscus plumifrons Cope, 1875

The plumed basilisk (Basiliscus plumifrons), also called commonly the green basilisk, the double crested basilisk, or the Jesus Christ lizard, is a species of lizard in the family Corytophanidae. The species is native to Central America.

Basiliscus plumifrons or known more commonly under the following colloquial names as the Green Crested Basilisk, Plumed Basilisk or Jesus Cristo Lizard is a species of lizard in the family Corytophanidae. The species is native to both Southern Mexico and spans in territory across Northern Colombia. The plumed basilisk typically occupies hot, humid rainforests that exist concurrently alongside streams. [1][3][5]

The physical appearance of the Plumed Basilisk known also as the Green Crested Basilisk is quite striking as it largely sports a bright green color along its body with black and white streaks along its neck and back. Their physical appearance differs based on sex, making them sexually dimorphic; males distinctly have a crest on the back and tail with visible, large plumes on top their head while females typically only have a singular, much smaller crest on their head. [1]

The green crested lizard or plumed lizard is unique in its ability to run across water and typically employs this feature when fleeing predators. This behavior is typically employed at a speed that is maintained in order to prevent sinking. [1][2]

This lizard is unordinarily territorial and is known for aggressive behavior to the extent where multiple male lizards cannot be maintained within the same enclosure. However, they do exist naturally in large groups that allow for multiple males. [1][6]

Habitat and Distribution

B. plumifrons’ habitat is isolated to the likes of Southern Mexican and Northern Colombian rainforests that are in close proximity to running streams. Their habitat is typically hot and humid in nature. This species typically resides in moist lowland habitats along with wet forests and alongside streams of mature forests.[1][8]

It is found to be that agroforestry systems, the integration of forest life (trees), to be necessary for the preservation of B. plumifrons. While B. plumifrons are native to Southern Mexico and Northern Colombian rainforests, there is evidence to suggest that the Plumed Basilisk occupies land across the Atlantic versant spanning from across eastern Honduras to western Panama. Additionally, B. Plumifrons have been sighted along the Pacific coast in southwestern Costa Rica. B. plumifrons is arboreal (preferential to tree landscape for their habitat), and diurnally active (active during the day), and of the three species of Basiliscus present in Costa Rica is found commonly on both versants (borders of land). [1][6]

Typically, B. plumifrons are understood to be aquatic lizards, found in heavy prevalence and widespread in Central American inland rivers, streams, ponds, and lakes. In addition to beaches and seashores. This species is unique in that it is both arboreal and aquatic and can be found in great prevalence in both trees and perched on boulders surrounded by water.[2][7]

The temperature preference of the B. Plumifrons has been reported to be 31.7*C +/- 0.5. [1]

Taxonomy and etymology

The Green basilisk's generic name Basiliscus is taken from the legendary reptilian creature of European mythology which could turn a man to stone by its gaze: the Basilisk. This name derives from the Greek basilískos (βασιλίσκος) meaning "little king". This generic name was given in Carl Linnaeus' 10th edition of Systema Naturae.

For the origin of the nickname "Jesus Christ lizard", see § Behaviour.

Description

Male plumed basilisk

The plumed basilisk is the largest basilisk species, with an average snout-to-vent length(SVL) of approximately 10 inches (25 cm). Including the tail, it can reach 3 feet (91 cm) in total length. Adults are brilliant green, with bright yellow eyes, and small bluish spots along the dorsal ridge. Males have three crests: one on the head, one on the back, and one on the tail, while females only have the head crest.Juveniles are less conspicuously colored, and lack the characteristic crests.

The green crested basilisk of B. plumifrons is a bright green lizard species found with varying streaks of white dark grey, and blue markings along its body. However, some alternative species of B. Plumifrons have been seen to sport only black markings along its dorsal side. The underbelly of this lizard is typically a lighter shade of green than the bright green that is shown throughout its body. It’s head is triangular from side view or profile, with openings for ears. These openings are slightly larger than the size of their eyes. The B. plumifrons are found most to have  round eyes, round pupils, and yellow irises. Small granular scales comprise the main covering for their skin. The length of the hind legs are longer than the front limbs as the hind legs are typically used for water running. In addition, their toes are laterally angled and flat to allow for water running. Adult males are found to have four prominent vertebrals crests: a dorsal crest, a tail crest, one atop the crown of the head, and one between their eyes. These crests form the greater physical distinction between female and male B. Plumifrons as female B. Plumifrons have only 2 (quite decreased in size) crests: a tail crest, and head crest. This aspect is shared amongst young and juvenile B. plumifrons. [1][2]

Video Clip

Predators

The predators of B. plumifrons include birds of prey, opossums, coati, and snakes.

Behaviour

Male plumed basilisks are territorial; a single male may defend a territory that several females inhabit, with which he mates. Plumed basilisks do not tolerate much handling when kept in captivity.

B. plumifrons is able to run short distances across the water using both its feet and tail for support, an ability shared with other basilisks and the Malaysian sail-finned lizard, When running, they create an air cavity which they use to push themselves forward with their feet which is mostly seen in adult basilisk lizards. The adults have a greater mass than juveniles so there is less hydrodynamic lag and they are able to run across the water in order to escape their predators. This has earned the plumed basilisk the nickname "Jesus Christ lizard". It is also an excellent swimmer and can stay underwater for up to an hour.

Most distinct to the B. Plumifrons is the ability to run across water. Typically, B. Plumifrons will employ this characteristic in response to perceived threats experienced by surrounding predators or predatory potential. They use this strategy most commonly when they are in fear or under duress. B. Plumifrons run bipedally (applying the use of both hind legs), utilizing both the foot and shank for immersion into water when their limbs are outstretched. Indeed many lizard species apply this feature (ie. Anolis aquaticus, A. barkeri), many perceive this behavior to be more advantageous than other lizard species who choose water diving or swimming as it allows for protection from other aquatic predators (such as; snakes, crocodiles, and large fish).[7]

The speed at which B. plumifrons is able to navigate water running, is determined largely by each individual’s hindlimb elongation potential. The hindlimb controls the locomotor gait and the stretch of the hindlimb allows for greater surface area and thus a greater velocity. In addition, it is proposed that the surface area of the lizard’s foot is a considerable factor in gaining speed. This is a unique benefit to the B. Plumifrons, as it has toes directed in a rotated orientation allowing for greater surface area of the foot to run across water. Typically the adult B. Plumifrons is able to run across water at a speed of 2.14m/s and lesser speed for juvenile B. Plumifrons. While other species of lizards do employ water running behaviors, it has been shown that B. Plumifrons are of the more preferential lizard species to water running and are typically less hesitant to utilize this skill. [7][2]

Running on Water

Basilisk lizards are notable for their remarkable ability to scamper across water from the time they are born. Both juvenile and adult basilisk lizards tend to use this unique trait to avoid predation. The mechanisms that allow these lizards to accomplish this task, however, remain generally unknown to researchers.

While some insects are able to run on water using surface tension, basilisk lizards, which have much more mass, achieve this through alternative fluid dynamics. This lizard will use its hind leg to penetrate the surface of the water beneath it to create an air-filled cavity and then retract its leg before the cavity closes. This enables the basilisk lizard to minimize its contact with water. Additionally, this running technique reduces the drag experienced during the run while simultaneously allowing the lizard’s body to be propelled across the water at an average speed of 1.6 m/s.

Although all Basilisk lizards harness this water-running ability, there is notably kinematic variation in these runs for these lizards - variation that is primarily due to differences in running velocity and not differences in the mass of the lizards running. This kinematic variation is unique to basilisk lizards. For other land lizards, kinematic variations in their running are generally similar. Studies have also indicated that the basilisks hindlimbs act as the primary force producer when they are running on water.

The basilisk lizard's remarkable ability to run on water has allowed scientists working with bipedal and quadrupedal robots to potentially create man-made technology that could also run on water through similar mechanisms.

Reproduction and Life Cycle

During the week prior to laying, sexually mature females of B. plumifrons were observed presenting herself to the male. The female would position herself about 0.5 m from the male, lowering her forebody to the sand and raising her pelvic region and tail.  Females lay five to fifteen eggs at a time in warm, damp sand or soil.  One mother lizard in captivity actually was observed to start digging holes (sometimes referred to as nests) in the soil six months prior to ovipositing, well ahead of the breeding season. The eggs hatch after eight to ten weeks, at which point they emerge as fully independent lizards, although averaging only 43mm SVL (Snout-to-Vent Length) and weighing only about 2 grams. The juvenile males would start to develop the large crests which are characteristic of the male B. plumifrons after six month or up to more than one year, depending on the body conditions of the juveniles.

Female B. Plumifrons are said to start showing or become plump one to two weeks post the breeding event. During the 3rd week of gestation, females will begin to search for a site to burrow or lay approximately 14-17 eggs. Typically, the size (no. in quantity of eggs) will vary depending on the lifestyle and physical characteristics of the mother (ie. age, health, and size). It is common for B. Plumifrons females to lay multiple clutches within a given season and this event will occur up to four or five times during a given breeding season. Hatching of eggs occurs over a one to two day period after a gestation and incubation period of eight to ten weeks. [6][7]

Diet

B. Plumifrons are an omnivorous species, their diet is inclusive of both meat and vegetation. While meat may be a stretch from their typical consumption, they choose to eat a large variety of insects and worms. While they are capable of consuming vegetation, it is less sought out in the wild as opposed to captivity for the B. plumifrons. While they do hunt smaller sized mammals such as fish and invertebrates, they are most often found in search of insects for their diet.

They typically consume brown crickets, black crickets, and locusts. In captivity, some owners choose to feed their B. Plumifrons or green crested lizard wax worms, calciworms, cockroaches, mealworms, and beetle worms on occasion. This latter selection of worms, roaches, and beetles are not the best suitable for the B. Plumifrons diet as they are found to be high in fat and can be difficult to digest for juvenile B. Plumifrons. [4]

References

1. Kupper, S. (2013). PROVIDING ENRICHMENT IN CAPTIVE AMPHIBIANS AND REPTILES: IS IT IMPORTANT TO KNOW THEIR COMMUNICATION? SMITHSONIAN HERPETOLOGICAL INFORMATION, (142), 10–13.
2. Hsieh, S. T. (2003). Three-dimensional hindlimb kinematics of water running in the plumed basilisk lizard (Basiliscus plumifrons). Journal of Experimental Biology, 206(23), 4363-4377.
3. Lattanzio, M. S., & LaDuke, T. C. (2012). Habitat use and activity budgets of emerald basilisks (Basiliscus plumifrons) in northeast Costa Rica. Copeia, 2012(3), 465-471. (habitat)
4. Cover Jr, J. F. (1986). Basiliscus plumifrons (Crested Green Brasilisk lizard). Food. Herpetological Review, 17, 19-19. (diet)
5. Vaughan, C., Ramirez, O., Herrera, G., Fallas, E., & Henderson, R. W. (2007). Home range and habitat use of Basiliscus plumifrons (Squamata: Corytophanidae) in an active Costa Rican cacao farm. Applied Herpetology, 4(3), 217. (habitat)
6. PAWLEY, R. (1972). Notes on reproduction and behaviour of the Green crested basilisk (Basiliscus plumifrons) at Brookfield Zoo, Chicago. International Zoo Yearbook, 12(1), 141-144. (reproduction)
7. Laerm, J. (1974). A functional analysis of morphological variation and differential niche utilization in basilisk lizards. Ecology, 55(2), 404-411 (habitat) (behavior)
8. LARA-RESENDIZ, R. A., RAMÍREZ-ENRÍQUEZ, Y. A. R. E. D. H., VALLE-JIMÉNEZ, I. S. A. Í., VALDEZ-VILLAVICENCIO, J. H., MÉNDEZ-DE LA CRUZ, F. R., & GALINA-TESSARO, P. A. T. R. I. C. I. A. River rocks as sleeping perches for Norops oxylophus and Basiliscus plumifrons in the Cordillera de Talamanca, Costa Rica. (habitat)

External links

• Green Basilisk. Honolulu Zoo web site.
• Image of Plumed Basilisk.
• https://animals.mom.me/types-animals-jesus-lizards-predator-6521.html.

Further reading

• Cope ED (1865). "On the Batrachia and Reptilia of Costa Rica. With notes on the Herpetology and Ichthyology of Nicaragua and Peru". J. Acad. Nat. Sci. Philadelphia, Second Series 8: 93-188. (Basiliscus plumifrons, new species, pp. 125–127).