Description
Osteopilus wilderi is a frog species, with snout-vent length that ranges from 24.2 to 29.2 mm in females and 24.3 to 27.9 mm in males (Schwartz and Fowler 1973). The head is wider than long, with the width about a third of the snout-vent length (Lynn et al. 1940). The snout is rounded, with the upper jaw protruding further than the lower jaw. The tongue is rounded, notched and wide (up to two thirds as wide as the open mouth). There are two sets of short vomerine teeth, which do not extend to the choanae. There is a space between the two sets that is the length of one set. The nostrils are located at the end of the snout. The loreal region is slightly concave. The eye diameter is equal to the distance from the eye to the nostril, and the eyelids cover about half of the entire eyeball. The tympanum is one half the diameter of the eye. The distance from the tympanum to the eye is approximately the same as, if not equal to, the diameter of tympanum. The head is smooth and has a soft texture, with no bumps or ridges. The skull is co-ossified and has a casque. The belly texture is more granular. There is no dermal fold (Dunn 1925).

The fingers are unwebbed. The second finger is longer than the first and the fourth finger is longer than the second. The toes are partially webbed (webbing extends one third of the way up each toe, reaching the distal phalanx) except for the first toe, which is free. There are two metatarsal tubercles, with the inner one being larger (Lynn et al. 1940). Male nuptial pads are enlarged (Luna et al. 2018).

Tadpoles have flattened bodies, possibly as an adaptation to their microhabitat: they occur exclusively in bromeliads. Their mouth is very small and circular. There is a labial disk with the upper lip continuing in a circle without bends or notches and the lower lip not being notched. There may be bumps around the labial disk. There are no labial teeth (Grant 1940).

Osteopilus wilderi is the smallest of the four Osteopilus species endemic to Jamaica. Osteopilus wilderi is often confused with the young of another Jamaican species, O. brunneas. Both species are also visually similar to O. dominicensis (from Hispaniola), and O. septentrionalis (in the greater Caribbean). Osteopilus wilderi differs from these three species by having a thumb pad, free skin on the head (not attached to the cranium), weak vomerine teeth, and less complete webbing between fingers and toes (Dunn 1925).

Osteopilus wilderi is also similar to two Haitian species, Boana heilprini and O. pulchrilineata. Both of the latter species also have unattached skin on the head, but they differ from O. wilderi in coloration (Dunn 1925).

The tadpoles of O. wilderi are small in comparison to the tadpoles of the three other Osteopilus species in Jamaica. Additionally, their tails are shorter than those of the other species on the island (Grant 1940).

In life, O. wilderi may be light yellow green (most common) or reddish brown. The belly is mostly white, but the underside of the head, neck, and limbs are all pale green. Their interocular bar is distinct. The bar and their eyelids are metallic silvery to metallic yellow green. Their interocular bar is sometimes bordered by a brown stripe both above and below the bar, but it may also just be bordered by subtler brown spots (Schwartz and Fowler 1973).

In preservative, O. wilderi are sage green with brown specks on the dorsal side of their body and limbs. The ventral side of the body and limbs is white. The pads of the hands and feet are white. The interocular bar is gray and bordered with brown. The bones of the limbs, specifically the tibia, can be seen through the skin (Lynn et al. 1940).

There is some sexual dimorphism. Females lack a thumb pad (Dunn 1925), and the interocular bar is more common in females than males. One study found that 41 of 54 females had the interocular bar, but only 4 of 43 males (Schwartz and Fowler 1973). Some data show that females are slightly larger than males, but other studies have concluded that there is no size sexual dimorphism in O. wilderi (Lynn et al. 1940).

Although most O. wilderi have homogeneously colored dorsal sides, some individuals may have silvery spots on their occiput and scapular regions. These spots may also be outlined with brown, similar to the outlining around the interocular bar (Schwartz and Fowler 1973).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Jamaica

	View distribution map in BerkeleyMapper.
	View Bd and Bsal data (2 records).

Osteopilus wilderi is found only in central Jamaica. Its elevational range is between 120 and 880 m. It is found in closed canopy, tropical and subtropical lowland forests, where it resides in terrestrial and arboreal bromeliads. The species also can exist in secondary forests as long as there are bromeliads present (Hedges et al. 2004).

Life History, Abundance, Activity, and Special Behaviors
The species is rather rare and is typically found in terrestrial and arboreal bromeliads. They occupy smaller bromeliads in comparison to the four other Osteopilus species in Jamaica (Dunn 1926).

Osteopilus wilderi displays the complex life cycle characteristic of metamorphosing frogs. Eggs are laid in small pools of water within bromeliads. When the tadpoles hatch, they rely on other eggs within the bromeliad as their main source of nutrients. It is theorized that the tadpoles may also eat other tadpoles living in the same bromeliad if undeveloped eggs don’t provide sufficient food (Dunn 1926).

Tadpoles of O. brunneus are known to prey on those of O. wilderi. Tadpoles of O. brunneus are typically found in large, tank bromeliads, which is one possible reason that eggs of O. wilderi are commonly laid in smaller bromeliads (Hedges 1987).

The diet of adult O. wilderi consists of small insects—mainly leafhoppers (Hemiptera: Cicadellidae) (Moen and Wiens 2009).

Male frogs call at night from tree limbs where bromeliads sit. The throat is inflated during the call (Dunn 1925). The call of O. wilderi is a five-note call that follows the rhythm “ticky-ticky-ticky-tick-tick.” The first tick is very fast and the last tick is most pronounced (Schwartz and Fowler 1973).

Trends and Threats
Osteopilus wilderi is currently listed by the IUCN as “Vulnerable” (Hedges et al. 2004). Populations of O. wilderi are on the decline due to residential and commercial development, deforestation for wood harvesting, and deforestation for the creation of agricultural lands. Due to the habitat specificity of O. wilderi (females lay eggs only in bromeliads), deforestation and urbanization has decimated tree populations and, subsequently, the epiphytic bromeliad populations that live on these trees. Terrestrial bromeliad populations have also been affected by deforestation and urbanization (Hedges et al. 2004).

On the eastern side of the island, O. wilderi occurs in one national park, the Blue and John Crow Mountain National Park, but stricter habitat protection laws and regulations are needed within this park (Hedges et al. 2004). Neither the Nature Conservancy nor Conservation International has yet to establish conservation models and monitoring systems for Jamaica in general (Hedges and Diaz 2011).

Comments
Equally weighted Parsimony and Maximum Likelihood analyses were conducted on the ribosomal 12S and 16S genes. Those analyses found that O. wilderi is sister to O. marianae (Blotto et al. 2020).

The genus name “Osteopilus” means “bone cap,” referring to the co-ossification of dorsal portions of the casque skull with the overlying integument, which is characteristic of all members of the genus (Dodd 2013).

Osteopilus wilderi has also been called Hyla wilderi (Dunn 1925), Hyla shrevei (Taylor 1952), and Hyla wilderae (Duellman 1977).

Osteopilus wilderi has been karyotyped; the diploid chromosome number (2N) equals 28 (Gruber et al. 2012).

In 2011, O. wilderi was one of only nine members of the family Hylidae (tree frogs) in the entire West Indies (Hedges and Diaz 2011).

References

Blotto, B.L., Lyra, M.L., Cardoso, M.C.S., Rodrigues, M.T., Dias, I.R., Marciano-Jr., E., Vechio, F.D., Orrico, V.G.D., Brandão, R.A., Assis, C.L., Lantyer-Silva, A.S.F., Rutherford, M.G., Gagliardi-Urrutia, G., Solé, M., Baldo, D., Nunes, I., Cajade, R., Torres, A., Grant, T., Jungfer, K.-H., da Silva, H.R., Haddad, C.F.B., Faivovich, J. (2020). ''The phylogeny of the Casque-headed Treefrogs (Hylidae: Hylinae: Lophyohylini).'' Cladistics [link]

Dodd, C. K. 2013. Frogs of the United States and Canada. John Hopkins University: JHU Press.

Duellman, W. E. (1977). ''Liste der rezenten Amphibien und Reptilien: Hylidae, Centrolenidae, Pseudidae.'' Das Tierreich, 95, 1-225.

Dunn, E. R. (1925). "A new tree-toad from Jamaica." Occasional Papers of the Boston Society of Natural History, 5, 161–162.

Gruber, S., Haddad, C., Kasahara, S. (2012). "Karyotype analysis of seven species of the tribe Lophiohylini (Hylinae, Hylidae, Anura), with conventional and molecular cytogenetic techniques." Comparative Cytogenetics, 6(4), 409-423.

Hedges, S. B. (1987). "Vocalization and habitat preference of the Jamaican treefrog, Hyla mariane (Anura, Hylidae)." Caribbean Journal of Science, 23, 380-384.

Hedges, S. B., Díaz, L. M. (2011). "The conservation status of amphibians in the West Indies." Conservation of Caribbean Island Herpetofaunas Volume 1: Conservation Biology and the Wider Caribbean. Brill, Leiden, The Netherlands, 31-47.

Hedges, S. B., Koenig, S., Wilson, B. (2004). Osteopilus wilderi. The IUCN Red List of Threatened Species 2004:e.T55812A11368630. https://dx.doi.org/10.2305/IUCN.UK.2004.RLTS.T55812A11368630.en. Downloaded on 20 April 2020.

Luna, M., McDiarmid, R., Faivovich, J. (2018). “From erotic excrescences to pheromone shots: Structure and diversity of nuptial pads in anurans.” Biological Journal of the Linnean Society, 124(3), 403–446.

Lynn, W., Grant, C., Lewis, C. (1940). . Bulletin of the Institute of Jamaica

Moen, D., Wiens, J (2009). "Phylogenetic evidence for competitively driven divergence: body-size evolution in Caribbean treefrogs (Hylidae: Osteopilus)." Evolution, 63(1), 195-214.

Powell, H. (2003). “A second set of addenda to the Checklist of West Indian Amphibians and Reptiles.” Herpetological Review, 34(4), 341–345.

Schwartz, A., Fowler, D. C. (1973). “The Anura of Jamaica: A progress report.” Studies on the Fauna of Curaçao and Other Caribbean Islands, 43(1), 50–142.

Taylor, E. H. (1952). "A new Panamanian tree frog." Breviora. Museum of Comparative Zoology, Cambridge, Massachusetts 1: 1–4.

Species Account Citation: AmphibiaWeb 2022 Osteopilus wilderi: Jamaican Green Treefrog <https://amphibiaweb.org/species/996> University of California, Berkeley, CA, USA. Accessed Nov 22, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 22 Nov 2024.

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