The species epithet, “marcoreyesi,” serves to honor and pay tribute to the original collector of this new species, Marco M. Reyes-Puig, who is a notable herpetologist in the herpetology division of Instituto Nacional de Biodiversidad (INABIO) (Franco-Mena et al. 2024).

Description
Centrolene marcoreyesi is a glass frog described from six adult males. The males have a snout-vent length range of 24.5 - 27.0 mm. The snout is rounded in the dorsal view and sloping in the lateral view. The nostrils are about one eye diameter length away from the eye. The loreal region is slightly concave with the internarial area only faintly depressed. The internarial distance is smaller than the interorbital distance. The small, anterolaterally-oriented eyes have a diameter that is only slightly smaller than the interorbital distance and only 10% of the snout-vent length. The tympanic annulus is distinct, but covered by the supratympanic fold on its posterior region. The tympanic membrane is distinguished and obviously thinner than the skin located along the tympanum. The dorsal skin texture is shagreen. There is a humeral spine that is small, arched, and tapers to a point at its distal end. The palm is covered with copious tubercles and with a large, oval shaped palmar tubercle and a faint or hard to distinguish thenar tubercle. Fingers I - III lack webbing and there is reduced webbing between Fingers III and IV with a formula of: III (2^⅓ – 2^¾) – (2^¼ – 2^⅔) IV. The disc on Finger III is smaller than the diameter of the eye, but larger than those on the toes. The finger discs are shortened, and the subarticular tubercles rounded. The slim legs have heels that intersect when pressed at a right angle to the body. The tibia length is about 60% of snout-vent length. The folds of the inner and outer ulnar and tarsal are not prominent. The inner metatarsal tubercle is large, broad, and oval-shaped while the outer metatarsal tubercle is not obvious. The granular planter possess abundant subarticular tubercles. The feet webbing has a formula of: I (1^½ – 1^⅔) – (2^– – 2) II (1⁺ – 1^¼) – (2^¼ – 2⁺) III (1^½ – 1^⅔) – (2^⅓ – 2^½) IV (2⁺ – 2^½) – (1^⅔ – 3^–) V. The toes tips are somewhat expanded and lack papillae (Franco-Mena et al. 2024).

Diagnosis:

The most similar species to C. marcoreyesi are: C. buckleyi, C. venezuelense, and C. elisae. These species have similar colorations that range from numerous shades of green with often lightly colored spot patterns on the dorsum. They also have similar distributions across the northern, central, and eastern slopes of the Andes. However, the Marco Reyes´ Glassfrog can be differentiated from these similar species by slight differences in color and patterns. Centrolene buckleyi is bright to dark green with some individuals having scattered olive-green spots; C. venezuelense is light green and has small cream-colored spots; C. elisae is dark green with small to minuscule white spots; and C. marcoreyesi is green with whitish spots. Centrolene marcoreyesi also has a small humeral spine in adult males and reduced webbing between the inner fingers. Additionally, based on snout-vent lengths of adult males, C. marcoreyesi is larger than C. elisae, but smaller than C. buckleyi and C. venezuelense. Centrolene marcoreyesi occupies a higher elevation than C. elisae, but a lower elevation than C. buckleyi and C. venezuelense. Lastly, C. marcoreyesi can be differentiated by its advertisement call structure. Namely, C. marcoreyesi has one note per call while C. elisae has two notes per call, and the two species do not overlap in dominant frequencies. Furthermore, C. marcoreyesi has much shorter calls with fewer pulses per note than C. buckleyi (Franco-Mena et al. 2024).

Coloration:

In life, C. marcoreyesi is noted for having green dorsal surfaces on the body, arms, and limbs as well as having abundant whitish spots of differing sizes. Its upper lip is yellowish-white as well as its anterior two-thirds of its venter, with the posterior third being translucent. The fingers, toes, and membranes are yellowish-green. The bones are green and the iris is white with a faint lavender hue and fine brown interlacing lines (Franco-Mena et al. 2024).

In preservative, the dorsum is lavender to grayish-lavender with yellowish-white to white spots. The venter is yellowish-cream, and the posterior third translucent. The anterior third to two-thirds of the parietal peritoneum is white, the hepatic peritoneal is translucent (Franco-Mena et al. 2024).

Variation:

One male had a marginally darker dorsum, and more dorsal barbs than other individuals. Additionally individuals from the type locality in the Estación Científica San Francisco have less webbing. At the time of the species description, females were unknown, thus sexual dimorphism could not be assessed (Franco-Mena et al. 2024).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Ecuador

View distribution map in BerkeleyMapper.

Centrolene marcoreyesi is endemic to the eastern slopes of the southern Ecuadorian Andes. It is known from four locations within this range including Estación Científica San Francisco, Abra de Zamora, Parque Nacional Podocarpus, and Guarumales, where it can be found near small streams in evergreen upper montane forest ecosystems. It occurs at altitudes between 1,840 – 2,190 m (Franco-Mena et al. 2024).

Life History, Abundance, Activity, and Special Behaviors
Centrolene marcoreyesi was found at night on ferns and leaves, above or near streams that vary in width, between 2 to 8 m. Males were observed in both primary and secondary forests, as well as along the margins of pastures (Franco-Mena et al. 2024).

A male was observed calling at night near a clutch of 19 eggs, one of which was dead (Franco-Mena et al. 2024).

Centrolene marcoreyesi has a “Tri” type of call that consists of one pulsed note. Calls last about 0.085 s, with notes having 8.1 pulses per note. The dominant frequency is 3.3 kHz, with increasing frequency with time. Inter-calls intervals have a mean time of 34.1 s, as well as a mean call rate of 1.8 calls/min (Franco-Mena et al. 2024).

At the Abra de Zamora site, Gastrotheca testudinea was also found, and in the Guarumales site, Nymphargus cariticommatus, N. posadae, N. cochranae, and member of the Hyalinobatrachium genus were also found (Franco-Mena et al. 2024).

Trends and Threats
As of 2024, C. marcoreyesi was not listed on the IUCN Red List, but even though some of this species’ habitat is within protected areas (Parque Nacional Podocarpus and Guarumales) it is threatened by habitat degradation due to cattle farming, invasive species, and mining. Additionally, the species only has an estimated extent of occurrence of < 100 km^². Thus, Franco-Mena et al. (2024) propose C. marcoreyesi be considered as “Endangered” based on their being known from only a few sites and with a small extent of occurrence and/or area of occupancy.

Possible reasons for amphibian decline

General habitat alteration and loss
Habitat modification from deforestation, or logging related activities
Intensified agriculture or grazing
Mining
Local pesticides, fertilizers, and pollutants
Introduced competitors

Comments
Based on Maximum Likelihood and Bayesian Inference analyses of 12S and 16S mitochondrial genes, C. marcoreyesi is thought to be sister to C. sabini, however there is only moderate support for this relationship (posterior probability = 0.82, bootstrap = 94) (Franco-Mena et al. 2024).

Synonyms:

Centrolene marcoreyesi was previously recognized as “Centrolene buckleyi [Ca1]” in a study by Amador et al. (2018) (Franco-Mena et al. 2024).

References
Amador, L., Parada, A., D’Elía, G., Guayasamin, J.M. (2018). Uncovering hidden specific diversity of Andean glassfrogs of the Centrolene buckleyi species complex (Anura: Centrolenidae). PeerJ, 6, e5856 [link]

Franco-Mena, D., De la Riva, I., Vega-Yánez, M.A., Székely, P., Amador, L., Batallas, D., Reyes-Puig, J.P., Cisneros-Heredia, D.F., Venegas-Valencia, K., Galeano, S.P., Culebras, J., Guayasamin, J.M. (2024). Simplifying the Centrolene buckleyi complex (Amphibia: Anura: Centrolenidae): a taxonomic review and description of two new species. PeerJ, 12, e17712. [link]

McCranie, J. R., and L. D. Wilson. (2002). The Amphibians of Honduras. Contributions to Herpetology, Volume 19. Oxford, Ohio: Society for the Study of Amphibians and Reptiles.

Species Account Citation: AmphibiaWeb 2025 Centrolene marcoreyesi: Marco Reyes´ Glassfrog <https://amphibiaweb.org/species/9866> University of California, Berkeley, CA, USA. Accessed May 11, 2025.

Citation: AmphibiaWeb. 2025. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 11 May 2025.

AmphibiaWeb's policy on data use.