AMPHIBIAWEB
Agalychnis moreletii
Black-eyed Tree Frog, Morelet's Treefrog
family: Hylidae
subfamily: Phyllomedusinae

© 2007 Dr. Peter Janzen (1 of 28)

View distribution map using BerkeleyMapper.


Conservation Status (definitions)
IUCN (Red List) Status Critically Endangered (CR)
See IUCN account.
CITES Appendix II
Other International Status None
National Status None
Regional Status None

   

Description
In adult males the SVL measures 60.5-64.2 mm, and the adult female holotype was measured to be 58.6 mm SVL. The snout is rounded in dorsal view, and obtuse in profile view. Nostrils are directed laterally. The loreal region is concave. A weak supratympanic fold runs above the tympanum and continues posterior to the tympanum. Fingers are extensively webbed, with relative lengths I< II< IV< III. Finger discs are broadly expanded with rounded covers. In breeding males, the prepollex bears small nuptial excrescences. Toe discs are broadly expanded, only slightly smaller than those of fingers. Skin is smooth to weakly granular dorsally, while ventral surfaces are coarsely areolate, except for the granular skin surrounding the vent. Pupil is vertically elliptical. Males have paired vocal slits and a single subgular vocal sac (McCranie and Wilson 2002).

Dorsal surfaces range from dark to light green (Lee 1996). Flanks, inner surfaces of the appendages, and the webbing between the first three fingers and first four toes are orange (Lee 1996). Ventral surfaces are light yellow or white (Lee 1996). The iris is dark red to deep purple (McCranie and Wilson 2002). The palpebral membrane has gold reticulations (Duellman 1970).

Tadpoles have a robust body that is deeper than it is broad. The tail is about twice the length of the body and is acuminate. Tail musculature is well developed. The spiracle is ventrolateral and sinistral. The vent tube opens to the right of the caudal fin. Papillae border the mouth parts, except on the dorsal surface of the upper lip. There are two upper and three lower rows of denticles. Tadpoles are purplish brown in coloration (Lee 1996).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Belize, El Salvador, Guatemala, Honduras, Mexico

View distribution map using BerkeleyMapper.
Agalychnis moreletii has a patchy distribution, from the Mexican states of Puebla in the northeast (Canseco-Márquez et al. 2000), Chiapas (Duellman 1970) south-central Veracruz (Duellman 1970) and Oaxaca (Duellman 1970) to northwestern Honduras (McCranie 2007) on the Atlantic versant and along the Pacific versant from south-central Guerrero, Mexico (Lee 1996) to western Belize (Maya Mountains) to central El Salvador (Santos-Barrera et al. 2004). The elevational range is about 650 to 1,300 m asl (Santos-Barrera et al. 2004). Its habitat consists of lowland to montane moist forests, both pristine and disturbed, on slopes (Santos-Barrera et al. 2004).

Life History, Abundance, Activity, and Special Behaviors
Males call in chorus, with a single "wor-or-orp" in intervals of one to two minutes with a dominant frequency of 1,100 to 1,260 Hz (Lee 1996). Briggs (2010) found that acoustic traits influenced mating success, with amplectant males making more calls, longer duration calls, and shorter pauses between calls. Also, heavier males emitted calls with lower dominant frequencies (Briggs 2008). Males sometimes compete for perch sites (Briggs 2008). Adults have been found on vegetation hanging above lakes (McCranie and Wilson 2002).

Females appear later in the season after heavy rains (Lee 1996). Breeding occurs in ponds (Lee 1996). Amplexus is axillary (Lee 1996). Briggs (2008) found that mating patterns varied; larger males had a mating advantage in the driest year of a three-year study of mating patterns, and size-assortative mating (by SVL) occurred in a different study year.

The eggs, which have a slight green tint, are deposited in discrete gelatinous clutches of about 50 to 75 on vegetation or rocks overhanging water (Lee 1996; Gomez-Mestre et al. 2008). Fertilization success is high, with Briggs (2008) reporting 100% fertilization in 45 of 46 experimental clutches, similar to her field observations. As is the case for A. callidryas and other species in the genus Agalychnis, embryos of A. moreletii exhibit adaptive plasticity in hatching timing (Gomez-Mestre et al. 2008). Normally, embryos begin hatching 9-12 days after eggs are deposited, with most embryos hatching at night and the hatching period lasting 2-3 days. However, embryos are competent to hatch earlier, when they reach Gosner stage 23 (where the operculum has covered the venter); this occurs about 7 days post-oviposition. Premature hatching occurs in response to either mechanical disturbance (such as occurs in snake predation of the clutch) or submergence.

Trends and Threats
Agalychnis moreletii is critically endangered. Populations in Mexico have almost entirely disappeared, likely due to chytridiomycosis (Lips et al. 2004; Frías-Alvarez et al. 2008), and chytridiomycosis has been reported in tadpoles of El Salvadoran populations of this species (Felger et al. 2007). A. moreletii is uncommon in Belize and Honduras (Santos-Barrera et al. 2004). Although it can tolerate some habitat disturbance, numbers are declining in Guatemala and Honduras due to habitat destruction from small farming (Santos-Barrera et al. 2004). Collection of this species for the pet trade has negatively affected population numbers (Santos-Barrera et al. 2004). A. moreletii occurs in a number of protected areas (Santos-Barrera et al. 2004), but additional localities need to be included if 25% of its potential distribution range is to be protected (Urbina-Cardona and Loyola 2008).

All five Agalychnis species (A. annae, A. callidryas, A. moreletii, A. saltator, and A. spurrelli) have just received CITES protection, under Appendix II (as of March 21, 2010). Within the past decade the U.S. alone has imported 221,960 Agalychnis frogs, according to the Species Survival Network (SSN).

Relation to Humans
Morelet's Treefrog was formerly quite common in the pet trade (Santos-Barrera et al. 2004).

Possible reasons for amphibian decline

Intensified agriculture or grazing
Disease
Intentional mortality (over-harvesting, pet trade or collecting)

Comments
The specific name moreletii is derived from Pierre-Marie Arthur Morelet, who was the collector of the syntypes (McCranie and Wilson 2002).

References

Briggs, V. S. (2008). ''Mating patterns of red-eyed treefrogs, Agalychnis callidryas and A. moreletii.'' Ethology, 114, 489-498.

Briggs, V. S. (2010). ''Call trait variation of Morelett’s trefrog, Agalychnis moreletii of Belize.'' Herpetologica, 66(3), 241-249.

Canseco-Márquez, L., Gutiérrez-Mayén, G., and Salazar-Arenas, J. (2000). ''New records and range extensions for amphibians and reptiles from Puebla, Mexico.'' Herpetological Review, 31, 259-263.

Duellman, W.E. (1970). The Hylid Frogs of Middle America. Volume 1. Monograph of the Museum of Natural History, University of Kansas.

Felger, J., Enssle, J., Mendez, D., and Speare, R. (2007). ''Chytridiomycosis in El Salvador.'' Salamandra, 43, 122-127.

Frías-Alvarez, P., Vredenburg, V. T., Familiar-López, M., Longcore, J. E., González-Bernal, E., Santos-Barrera, G., Zambrano, L., and Parra-Olea, G. (2008). ''Chytridiomycosis survey in wild and captive Mexican amphibians.'' EcoHealth, 5, 18-26.

Gomez-Mestre, I., Wiens, J. J., and Warkentin, K. M. (2008). ''Evolution of adaptive plasticity: risk-sensitive hatching in neotropical leaf-breeding treefrogs.'' Ecological Monographs, 78, 205-224.

Johnson, J. D., Ely, C. A., and Webb, R. G. (1976). ''Biogeographical and taxonomic notes on some herpetozoa from the northern highlands of Chiapas, Mexico.'' Transactions of the Kansas Academy of Science (1903-), 79, 131-139.

Lee, J. C. (1996). The Amphibians and Reptiles of the Yucatan Peninsula. Cornell University Press, Ithaca, New York.

Lips, K. R., Mendelson, J. R. III, Munoz-Alonso, A., Canseco-Marquez, L. and Mulcahy, D.G. (2004). ''Amphibian population declines in montane southern Mexico: resurveys of historical localities.'' Biological Conservation, 119, 555-564.

Lynch, J. D., and Fugler, C. M. (1965). ''A survey of the frogs of Honduras.'' Journal of the Ohio Herpetological Society, 5, 5-18.

McCranie, J. R. (2007). ''Distribution of the amphibians of Honduras by departments.'' Herpetological Review, 38(1), 35-39.

McCranie, J. R., and Wilson, L. D. (2002). ''The Amphibians of Honduras.'' Contributions to Herpetology, Vol 19. K. Adler and T. D. Perry, eds., Society for the Study of Amphibians and Reptiles, Ithaca, New York.

Santos-Barrera, G., Lee, J., Acevedo, M., Wilson, L.D. (2004). Agalychnis moreletii. In: IUCN 2009. IUCN Red List of Threatened Species. Version 2009.1. www.iucnredlist.org. Downloaded on 02 November 2009.

Urbina-Cardona, J. N. and Loyola, R. D. (2008). ''Applying niche-based models to predict endangered-hylid potential distributions: are neotropical protected areas effective enough?'' Tropical Conservation Science, 1, 417-445.



Written by Sandya Iyer (sandya.iyer AT berkeley.edu), UC Berkeley
First submitted 2009-11-02
Edited by Kellie Whittaker (2011-09-27)



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Citation: AmphibiaWeb: Information on amphibian biology and conservation. [web application]. 2016. Berkeley, California: AmphibiaWeb. Available: http://amphibiaweb.org/. (Accessed: Jun 29, 2016).

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