Description
Distinguished from all other Costa Rican hylids, with the exception of Hyla fimbrimembra, by the presence of dermal fringes along the posteroventral margins of the limbs (Savage and Heyer 1968). It differs from H. fimbrimembra in lacking true integumentary-cranial co-ossification, although the presence of osteoderms belays a false impression of this character (Duellman 1970). Other distinguishing features include fully webbed hands and feet, and tuberculate skin that is present in both juveniles and adults. Adults have keratinized granules on their venter, and breeding males have protruding prepollical spines.

The head is flat on top and rounded in dorsal outline, and the snout appears truncate in both dorsal and lateral outline. The tympanum is about half the size of the eye, and above it a bony ridge followed by a dermal fold extends posteriorly to just above the arm's insertion. The canthus is rounded and the internarial area is depressed. Arms are short and robust, and the immense hand bears large discs. The legs are long and moderately robust, and the feet also bear large discs. Recorded snout-vent length measurements ranged from 57.2 to 106.0 mm for male adults, and 69.7 mm for the single collected female (all above descriptions from Duellman 1970).

The dorsal coloration is mottled with dark brown, metallic green, and orange-tan, while ventral surfaces range from pink-tan to light-brown, except for the anal region which is creamy white. The chin has white tubercles and dark brown spots, the tympanum, webbing, and discs are dark brown, and the iris is bronze with reddish-brown reticulations (all color descriptions from Duellman 1970).

No call has been attributed to this species, although a "loud growl-like" sound has been noted (Duellman 1970).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Colombia, Costa Rica, Honduras, Nicaragua, Panama

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

Collections of H. miliaria have been extremely rare, thus a collecting bias limits the known distribution. This species has been collected between 600 and 1200 m on both the Caribbean and Pacific highland slopes of western Panama and Costa Rica, and from an unknown locality in Nicaragua and central Colombia (Duellman 1970). The habitat is humid rainforest, categorized in the Subtropical Rainforest Lifezone using the designations of Holdridge (1967).

Life History, Abundance, Activity, and Special Behaviors
Very little information is available for H. miliaria. The thick, rugose skin and presence of osteoderms may provide some protection against desiccation, perhaps enabling the frogs to live in a more arid microhabitat (Duellman 1970). An arboreal lifestyle is indicated by the large discs and dermal fringes, the latter seeming to confer the ability of gliding although only two observations have provided evidence for this behavior. The arboreal lifestyle and resilience to desiccation has been suggested as evidence for the Fringe-limbed treefrog's home in the forest canopy (Duellman 1970).

There is not enough data available to estimate species abundance.

Trends and Threats
Due to the extreme rarity of sightings and lack of demographic data for H. miliaria, it's conservation status remains unknown.

Comments
Older nomenclature refers to Hyla miliaria as H. immensa. For a summary of name history, refer to Duellman (1970).

A Spanish-language species account can be found at the website of Instituto Nacional de Biodiversidad (INBio).

References

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

Holdridge, L. R. (1967). Life Zone Ecology. Tropical Science Center, San Jose, Costa Rica.

Savage, J. M., and Heyer, W. R. (1968). ''The tree-frogs (Family Hylidae) of Costa Rica: diagnosis and distribution.'' Revista de Biologia Tropical, 16(1), 1-127.

Species Account Citation: AmphibiaWeb 2021 Ecnomiohyla miliaria: Cope's Brown Treefrog <https://amphibiaweb.org/species/871> University of California, Berkeley, CA, USA. Accessed Nov 12, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 12 Nov 2024.

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