Basil
02-15-2008, 12:32 AM
Bromeliad Boa
Ungaliophis continentalis
I. Introduction
It is difficult to imagine a boa that has not been exhaustively studied and become the subject of numerous publications. However, there are a few that have successfully evaded their fifteen minutes of fame, one of these being the Bromeliad Boa. When I first learned of the dwarf boa from Central America I was volunteering at the Fort Worth Zoo, and I became fascinated by the little snake. This fascination quickly became an obsession when I discovered how difficult it would be to uncover every tidbit of information. After nearly a full year of research I have learned a lot about the Bromeliad Boa, but one lesson is resoundingly clear: This is truly one elusive serpent!
II. Classification
The Bromeliad Boa is known by a host of names: Banana Boa, Neotropical Dwarf Boa, Central American Dwarf Boa, just to name a few. The taxonomy of the Bromeliad Boa is worthy of its own Six Flags ride. Ungaliophis began its existence as a member of Tropidophiinae, a sub-family of Boidae. Tropidophiinae included four genera: The first, Tropidophis, consisting of 15 species. This genus has the remarkable ability to secrete blood from its eyes and mouth when under duress, similar to some of the Horned Lizards (Phrynosoma). Trachyboa, the second, contains two heavily keeled species. Exiliboa placate, a third genus with only one species, is a beautiful solid black snake that was only recently discovered in 1968. And finally, Ungaliophis, which contains the two species continentalis and panamensis. U. panamensis has a more southern range than U. continentalis, and has triangular black spots on its dorsal instead of the ovoid markings of its sister species. (Mehrtens, 1987) The Tropidophids then became their own family Tropidophidae. Until recently, this has been the most widely accepted grouping. In the latest phylogenetic anylasis, preformed by Wilcox et al, it has been determined that Ungaliophis and Exiliboa are much more closely related to the boas (Boinae) than they are to their counterparts: Tropidophis and Trachyboa. Therefore it was suggested that Ungaliophis and Exiliboa become their own family, Ungaliophiidae. (Wilcox et al, 2002) The acceptance of this grouping is becoming more apparent in the publishing of recent books, such as Snakes of Costa Rica by Alejandro Solórzano.
III. Description
The Bromeliad boa is a small snake with a slender build. Its small, somewhat flat head is clearly differentiated from its neck. It can have a base color of gray, bronze, or medium brown. There is a large black bifurcated (branched) marking on the crown of its head turning into two short cervical stripes. Continuing down the dorsal area are two rows of black ovoid markings, each incased in a small yellow or cream colored ring. The ventral section is moderately speckled with blacks, browns, pinks, and white.
U. continentalis are sexually dimorphic in size. The females are larger averaging 22” to 24” while the males are typically 18” to 20”. However, the females are nearly double the males’ weight at 55 grams to their 20-25 grams. (Burger, 1998)
IV. Habitat
The first Bromeliad Boa was discovered in Guatemala in 1878 by Friz Muller. The record of the sighting was published in 1882. There were only approximately seven more sightings until the mid 1960’s. It was later determined that the range of U. continentalis extended from Chiapas, Mexico south to the Honduras. They were found to inhabit a large range of elevations from 400’ in Guatemala to 7,000’ in Chiapas. This included tropical lowland forests to upland pine forests. (Burger, 1998) One Honduran specimen was collected at 5250’ elevation with an average annual temperature of only 64°F. Another specimen was collected in the Guatemalan Costal Lowland at 650’ elevation with an average temperature of 75-80°F. (Burger, 1995)
Bromeliad Boas can typically be found both in and under arboreal vegetation such as horizontal branches covered with mosses, ferns, orchids, and bromeliads. They are also sometimes found in banana trees, hence their alias Banana Boas.
V. Prey & Behavior
The secretive nature and arboreal habitat of the Bromeliad Boa is a significant obstacle to direct observation and obstructs even the most basic information gathering. Little is known of the snakes’ feeding habits and other behaviors. To date no specimen has been collected with remains in its stomach. However, herpetologists have found that collected specimens will feed on pinky mice, lizards, and small frogs. Neonates have also been successfully given minnows as prey items. (Burger, Pers. Comm.) The successful consumption of minnows and the willingness to feed on frogs suggests the link between the boas and the bromeliad plant. Frogs are known to use the bromeliads as vestibules in which to deposit their eggs. The water retained in the leaves provides a home for developing tadpoles and a food source for the arboreal snake.
The Bromeliad Boa is sometimes referred to as an arboreal burrower. It spends most of its time in the trees, but buries itself under the moss and dead foliage that collects in the tree branches. It is a nocturnal snake, and uses constriction to overcome its prey. It is not an aggressive species and makes no attempt to bite when uncovered in the wild. (Corn, 1974) It only seeks to defend itself by coiling tightly in a ball to protect its head.
VI. Reproduction
The reproductive nature of the Bromeliad Boa is very unique. There are some male snakes that will bite the female’s neck while breeding. But the Bromeliad Boa is the only snake known to engage in a coital tail bite. The male will grasp the female by the tail, and maintaining the hold it will coil its lower portion around the female using its spurs (1-2mm) to position its body. The male will maintain the bite throughout the entire mating attempt, which is usually less than one hour. (Burger, 1998)
The gestation period for these snakes is five to six months. Due to the males eagerness to breed it is difficult to determine the exact number of days. The size of the litter remains small at two to ten neonates with an average of six. The neonates are typically six inches long when born. (Burger, 1995) Males become reproductively active before their second year, while females become so between their second and third years. (Burger, 1998)
VII. Abundance
As a result of the Bromeliad Boa’s elusive lifestyle, it is difficult to estimate their abundance. The techniques used for collecting herps contribute to the lack of Ungaliophis found in the wild. One must search the treetops to uncover this diminutive snake, which is a collecting technique rarely used. (Corn, 1974) CITES (Convention on International Trade in Endangered Species) has listed Ungaliophis in Appendix II. Appendix II includes species not necessarily threatened with extinction, but in which trade must be controlled in order to avoid utilization incompatible with their survival.
Studies suggest that their continued existence is precarious due to increased contact with predators, banana workers, pesticides, and deforestation. (Corn, 1974)
VIII. Husbandry
Once established Bromeliad Boas are easy captives. The most difficult part is getting the neonates started. A few researchers have had some success tease feeding these little serpents using mouse tails or anole tails. Another has reported using small minnows to get them started. As adults the snakes can be fed two small pinky mice every other week as their staple diet. Bromeliad Boas tend to be easily startled and if caught off guard will refuse to eat, so care must be taken not to spook them while feeding.
Temperatures should remain in the seventies, not to exceed the low eighties. A night time drop into the mid-sixties is acceptable. Humidity is ideal between 65% and 70%. Because of this species’ natural behavior of burrowing under leaf litter in the tops of trees an elevated humidity hide is highly recommended. Peat or sphagnum mosses are an excellent choice for retaining humidity in the hides. A ten gallon aquarium or similar sized enclosure gives the boas plenty of room to move around and explore. A great addition to Bromeliad Boa enclosures are live plants. Because of this species diminutive stature live plants thrive without being crushed. The snakes also tend to hide amongst the foliage. Pothos, bromeliads and ficus are just a few of the plants that could be used. The record for longevity in this species is 17 years.
Bromeliad Boas make excellent captives because of their small size and subtle beauty. However, they are very rarely found in captivity, so should you find an opportunity to purchase one of these awesome snakes consider yourself very fortunate!
I would like to thank Michael Burger for his generosity in sharing his personal experience and information. I would also like to thank Jonathan Campbell for his assistance in locating scientific journals.
IX. References
Burger, R. Michael. 1995. “An Arboreal Burrower: The Dwarf Boa Ungaliophis.” The Vivarium. Vol. 7 No. 2
Burger, R. Michael. 1998. “The Bromeliad Boa.” Reptiles Magazine. Vol. 6 No. 6
Corn, Michael J. 1974. “Report On The First Certain Collection Of Ungaliophis panamensis From Costa Rica.” Caribbean Journal of Science. Vol.14 Nos. 3-4
Mehrtens, John M. 1987. Living Snakes of the World. Sterling Publishing Co., New York.
Wilcox, Thomas P.; Zwickl, Derrick J.; Heath, Tracy A.; Hillis, David M. 2002. “Phylogenetic relationships of the dwarf boas and a comparison of Bayesian and bootstrap measures of phylogenetic support.” Mol. Phylogen. & Evol. 25: 361-371.
Ungaliophis continentalis
I. Introduction
It is difficult to imagine a boa that has not been exhaustively studied and become the subject of numerous publications. However, there are a few that have successfully evaded their fifteen minutes of fame, one of these being the Bromeliad Boa. When I first learned of the dwarf boa from Central America I was volunteering at the Fort Worth Zoo, and I became fascinated by the little snake. This fascination quickly became an obsession when I discovered how difficult it would be to uncover every tidbit of information. After nearly a full year of research I have learned a lot about the Bromeliad Boa, but one lesson is resoundingly clear: This is truly one elusive serpent!
II. Classification
The Bromeliad Boa is known by a host of names: Banana Boa, Neotropical Dwarf Boa, Central American Dwarf Boa, just to name a few. The taxonomy of the Bromeliad Boa is worthy of its own Six Flags ride. Ungaliophis began its existence as a member of Tropidophiinae, a sub-family of Boidae. Tropidophiinae included four genera: The first, Tropidophis, consisting of 15 species. This genus has the remarkable ability to secrete blood from its eyes and mouth when under duress, similar to some of the Horned Lizards (Phrynosoma). Trachyboa, the second, contains two heavily keeled species. Exiliboa placate, a third genus with only one species, is a beautiful solid black snake that was only recently discovered in 1968. And finally, Ungaliophis, which contains the two species continentalis and panamensis. U. panamensis has a more southern range than U. continentalis, and has triangular black spots on its dorsal instead of the ovoid markings of its sister species. (Mehrtens, 1987) The Tropidophids then became their own family Tropidophidae. Until recently, this has been the most widely accepted grouping. In the latest phylogenetic anylasis, preformed by Wilcox et al, it has been determined that Ungaliophis and Exiliboa are much more closely related to the boas (Boinae) than they are to their counterparts: Tropidophis and Trachyboa. Therefore it was suggested that Ungaliophis and Exiliboa become their own family, Ungaliophiidae. (Wilcox et al, 2002) The acceptance of this grouping is becoming more apparent in the publishing of recent books, such as Snakes of Costa Rica by Alejandro Solórzano.
III. Description
The Bromeliad boa is a small snake with a slender build. Its small, somewhat flat head is clearly differentiated from its neck. It can have a base color of gray, bronze, or medium brown. There is a large black bifurcated (branched) marking on the crown of its head turning into two short cervical stripes. Continuing down the dorsal area are two rows of black ovoid markings, each incased in a small yellow or cream colored ring. The ventral section is moderately speckled with blacks, browns, pinks, and white.
U. continentalis are sexually dimorphic in size. The females are larger averaging 22” to 24” while the males are typically 18” to 20”. However, the females are nearly double the males’ weight at 55 grams to their 20-25 grams. (Burger, 1998)
IV. Habitat
The first Bromeliad Boa was discovered in Guatemala in 1878 by Friz Muller. The record of the sighting was published in 1882. There were only approximately seven more sightings until the mid 1960’s. It was later determined that the range of U. continentalis extended from Chiapas, Mexico south to the Honduras. They were found to inhabit a large range of elevations from 400’ in Guatemala to 7,000’ in Chiapas. This included tropical lowland forests to upland pine forests. (Burger, 1998) One Honduran specimen was collected at 5250’ elevation with an average annual temperature of only 64°F. Another specimen was collected in the Guatemalan Costal Lowland at 650’ elevation with an average temperature of 75-80°F. (Burger, 1995)
Bromeliad Boas can typically be found both in and under arboreal vegetation such as horizontal branches covered with mosses, ferns, orchids, and bromeliads. They are also sometimes found in banana trees, hence their alias Banana Boas.
V. Prey & Behavior
The secretive nature and arboreal habitat of the Bromeliad Boa is a significant obstacle to direct observation and obstructs even the most basic information gathering. Little is known of the snakes’ feeding habits and other behaviors. To date no specimen has been collected with remains in its stomach. However, herpetologists have found that collected specimens will feed on pinky mice, lizards, and small frogs. Neonates have also been successfully given minnows as prey items. (Burger, Pers. Comm.) The successful consumption of minnows and the willingness to feed on frogs suggests the link between the boas and the bromeliad plant. Frogs are known to use the bromeliads as vestibules in which to deposit their eggs. The water retained in the leaves provides a home for developing tadpoles and a food source for the arboreal snake.
The Bromeliad Boa is sometimes referred to as an arboreal burrower. It spends most of its time in the trees, but buries itself under the moss and dead foliage that collects in the tree branches. It is a nocturnal snake, and uses constriction to overcome its prey. It is not an aggressive species and makes no attempt to bite when uncovered in the wild. (Corn, 1974) It only seeks to defend itself by coiling tightly in a ball to protect its head.
VI. Reproduction
The reproductive nature of the Bromeliad Boa is very unique. There are some male snakes that will bite the female’s neck while breeding. But the Bromeliad Boa is the only snake known to engage in a coital tail bite. The male will grasp the female by the tail, and maintaining the hold it will coil its lower portion around the female using its spurs (1-2mm) to position its body. The male will maintain the bite throughout the entire mating attempt, which is usually less than one hour. (Burger, 1998)
The gestation period for these snakes is five to six months. Due to the males eagerness to breed it is difficult to determine the exact number of days. The size of the litter remains small at two to ten neonates with an average of six. The neonates are typically six inches long when born. (Burger, 1995) Males become reproductively active before their second year, while females become so between their second and third years. (Burger, 1998)
VII. Abundance
As a result of the Bromeliad Boa’s elusive lifestyle, it is difficult to estimate their abundance. The techniques used for collecting herps contribute to the lack of Ungaliophis found in the wild. One must search the treetops to uncover this diminutive snake, which is a collecting technique rarely used. (Corn, 1974) CITES (Convention on International Trade in Endangered Species) has listed Ungaliophis in Appendix II. Appendix II includes species not necessarily threatened with extinction, but in which trade must be controlled in order to avoid utilization incompatible with their survival.
Studies suggest that their continued existence is precarious due to increased contact with predators, banana workers, pesticides, and deforestation. (Corn, 1974)
VIII. Husbandry
Once established Bromeliad Boas are easy captives. The most difficult part is getting the neonates started. A few researchers have had some success tease feeding these little serpents using mouse tails or anole tails. Another has reported using small minnows to get them started. As adults the snakes can be fed two small pinky mice every other week as their staple diet. Bromeliad Boas tend to be easily startled and if caught off guard will refuse to eat, so care must be taken not to spook them while feeding.
Temperatures should remain in the seventies, not to exceed the low eighties. A night time drop into the mid-sixties is acceptable. Humidity is ideal between 65% and 70%. Because of this species’ natural behavior of burrowing under leaf litter in the tops of trees an elevated humidity hide is highly recommended. Peat or sphagnum mosses are an excellent choice for retaining humidity in the hides. A ten gallon aquarium or similar sized enclosure gives the boas plenty of room to move around and explore. A great addition to Bromeliad Boa enclosures are live plants. Because of this species diminutive stature live plants thrive without being crushed. The snakes also tend to hide amongst the foliage. Pothos, bromeliads and ficus are just a few of the plants that could be used. The record for longevity in this species is 17 years.
Bromeliad Boas make excellent captives because of their small size and subtle beauty. However, they are very rarely found in captivity, so should you find an opportunity to purchase one of these awesome snakes consider yourself very fortunate!
I would like to thank Michael Burger for his generosity in sharing his personal experience and information. I would also like to thank Jonathan Campbell for his assistance in locating scientific journals.
IX. References
Burger, R. Michael. 1995. “An Arboreal Burrower: The Dwarf Boa Ungaliophis.” The Vivarium. Vol. 7 No. 2
Burger, R. Michael. 1998. “The Bromeliad Boa.” Reptiles Magazine. Vol. 6 No. 6
Corn, Michael J. 1974. “Report On The First Certain Collection Of Ungaliophis panamensis From Costa Rica.” Caribbean Journal of Science. Vol.14 Nos. 3-4
Mehrtens, John M. 1987. Living Snakes of the World. Sterling Publishing Co., New York.
Wilcox, Thomas P.; Zwickl, Derrick J.; Heath, Tracy A.; Hillis, David M. 2002. “Phylogenetic relationships of the dwarf boas and a comparison of Bayesian and bootstrap measures of phylogenetic support.” Mol. Phylogen. & Evol. 25: 361-371.