AmphibiaWeb - Atelopus mittermeieri
Atelopus mittermeieri
family: Bufonidae
Species Description: Velasquez-Alvarez, Sanchez-Pacheco, Pena Prieto et al. 2006 Discovery of a new species of Atelopus (Bufonidae) for Colombia: a hope or the eclipse of harlequin toads. Rev Acad Colomb Cienc Exactas Fis Nat 30: 281

© 2010 Andrés Acosta (1 of 1)
Conservation Status (definitions)
IUCN (Red List) Status Endangered (EN)
National Status None
Regional Status None



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


The body of Atelopus mittermeieri is robust and the snout-vent length is 32.99 - 33.36 mm for males and 41.33 - 44.95 mm for females. In the dorsal view, the snout is triangular, and tapers to a point in the lateral view. The snout is rounded at the end and very bulky toward the outer edges. The upper jaw protrudes past the lower a little bit. The supralabial region is somewhat defined. The external nostrils are in the dorsolateral area, are closer to the rostral end of the orbit than the anterior angle of the orbit, and are close in height to the mandibular symphysis. The nostrils have somewhat ovoid openings, protrude slightly, and are oblique in the anteroventral direction. The canthus rostralis is round and thick. The loreal region is concave, angled inward, and not really wide. The transverse diameter of the eye is slightly greater than the nostril-eye length. The upper eyelid is fleshy and thick. The parotoid glands are defined and long, their length is nearly twice the width, and they are arranged dorsolaterally and continue from the posterior edge of the eyelid to a point that is dorsal to the insertion of the arm. It has a flat dorsal surface of the cephalic region. The males lack defined vocal sacs and the species lacks the eardrum, tympanic membrane, and tympanic ring (Acosta-Galvis et al. 2006).

Males have strong forearms while females have more delicate and somewhat thicker forearms. The webbing of the hands is minimal. When the arms are adpressed toward the posterior and the legs are adpressed toward the anterior, the elbows and knees do not overlap in females and overlap somewhat in males. The oval thenar tuberlce is not very prominent, hardly visible. The supernumerary tubercles are large, flat, and round. The fingers are long, do not have dermal ridges, and are round at the distal end. The relative finger lengths are I < II < III < IV. The distal end of finger II continues to the base of the subarticular tubercle of the second phalange of finger III. The subarticular tubercles are not very prominent and the basal ones are somewhat ovoid.The first finger of males is thick, short, and curved. Male has nuptial outgrowths consisting of thin spinules that cover the back of the pollex and the second toe’s base (Acosta-Galvis et al. 2006).

The hindback limbs are slim. When the legs are adpressed along the body, the external metatarsal tubercle reaches the median level of the orbit or further. When the legs are held at right angles to the body and the thighs are perpendicular to the sagittal plane, the heels touch. The external metatarsal tubercle is small, round, and elevated. The internal metatarsal tubercle is nearly three times larger than the external metatarsal tubercle. There are few supernumerary tubercles. The subarticular tubercles are subtle and slightly elevated. The toes are pointed, somewhat dilated. The relative toe lengths are I < II < IV < V < III. The third toe is a little longer than the fifth. The webbing in the feet is thick, low, and extended (Acosta-Galvis et al. 2006).

On the back of the head, the skin is smooth. The dorsal skin of the body has flattened tubercles and dispersed white spicules that are uniformly distributed and not very prominent in females while they are more elevated in males. There are many large, elevated tubercles on the exposed surfaces of the forelimbs, legs, and feet. From the lateral view, the sides of the head have smooth surfaces in the loreal, supraorbital, and supralabial regions, while there are large tubercles on the postorbital region. Some specimens have large, concentrated, protruding pustules in the postorbital region. The flanks have large flattened tubercles and some dispersed pustules, but these can vary; some specimens have more concentrated raised tubercles while the surface was smooth with dispersed tubercles in an adult female. The unexposed surfaces are smooth. The anterior and posterior thighs have fine granules and there are some hardly visible tubercles closer to the knee. The ventral surfaces, anterior region of the gular, and the chest and stomach are smooth and have some dispersed granules and tubercles. The limbs’ ventral surfaces have fine granules (Acosta-Galvis et al. 2006).

At Gosner stage 25, one individual larvae had a snout-vent length of 5.19 mm and a total length of 11.32 mm. At Gosner stage 26, one individual had a snout-vent length of 5.24 mm and a total length of 11.56 mm. At gosner stage 27, three individuals ranged from 5.23 - 5.33 mm in snout-vent length and 11.92 - 12.01 mm in total length. At Gosner stage 28, one individual had a snout vent length of 5.27 mm and a total length of 13.03 mm. At Gosner stage 29, two individuals ranged from 5.43 - 5.45 mm in snout-vent length and 12.34 - 12.53 mm in total length. At Gosner stage 30, two individuals ranged from 5.46 - 6.08 mm in snout-vent length and 12.97 - 13.03 in total length. At Gosner stage 31, one individual had a snout-vent length of 6.36 mm and a total length of 13.93 mm. At Gosner stage 32, three individuals ranged from 5.32 - 6.12 mm in snout-vent length and 12.16 - 13.74 mm in total length. At Gosner stage 33, two individuals ranged from 5.55 - 6.10 mm in snout-vent length and 12.93 - 13.89 mm in total length. At Gosner stage 34, one individual had a snout-vent length of 6.66 mm and a total length of 14.77 mm (Acosta-Galvis et al. 2006).

Larvae in Gosner stages 27 - 34 have a short and ovoid body in dorsal view. The snout is shaped like a semicircle, round and truncated. The body’s width is greater than its height. The canthus rostralis is not clearly seen. The nostrils are ovoid with a low edge in the dorsal side, do not protrude, and open at the same level as the body’s surface. The nostrils are closer to the eye than the snout's end and can be seen from the dorsal, frontal, and lateral views. The eyes are small and are arranged dorsally. The gular region is convex. The oral disc is large and notched in the ventral direction, and is in a ventral subterminal position. The anterior and posterior edges of the oral disc are smooth and are not divided by an angular slit on both sides. The marginal papillae are in one to two rows and extend to the inner edge of the suction cup, but do not touch it. There are also marginal papillae in the lateral region of the oral disc. The abdominal suction cup is shaped like the letter U, opens in the direction of the oral disc, and is separated from the proctodeal tube. The abdominal suction cup is never wider than the body, and it is about half of less of the body length. The branchial region is a more flattened concave shape and the abdominal region is a more flattened convex shape. The spiracle is visible from the dorsal view and it begins in the middle of the body. It has a short tube which protrudes from the side of the body in the posterolateral direction. The caudal length is greater than the body length. The tail is rounded at the posterior end. The dorsal fin begins on the tail. The anterior edge of the dorsal fin is somewhat concave and it is tallest at the middle level of the tail. The ventral fin begins close to the vent tube and has a straight edge. The caudal musculature is taller in the proximal half, narrows from there, and does not reach the end of the fin (Acosta-Galvis et al. 2006).

Adult A. mittermeieri can be differentiated from A. ebenoides, subspecies marinkellei, by the former’s red belly and the latter’s uniform black body with small white spots, and their snout-vent lengths; males of the former have a snout-vent length ranging 32.99 - 33.36 mm while males of the latter's length is 44.5 mm (Acosta-Galvis et al. 2006).

The larvae of A. mittermeieri are similar to the larvae of the species A. ebenoides marinkellei, A. muisca, A. nahumae, A. quimbaya, A. sernai, A. minutulus, and A. nicefori due to their uniform black or brown coloration on the body. The larvae of A. mittermeieri are similar to the larvae of A. subornatus because black and cream coloration of the caudal bands can appear in both species (Acosta-Galvis et al. 2006).

In life, the dorsal surface of the head, body, forelimbs, and hind limbs are dark brown to black and have some small, scattered white spots that are shorter than the diameter of the eye. From the lateral view, the sides and dorsal surface of the head are the same color and have a white spot in the infraorbital region. The flank is red-brown. The hidden surfaces, groin, and front and dorsal thighs are brown. Ventrally, the anterior side of the gular and chest switches between brown and black and the belly and thighs are red, and these areas have irregular brown spots. The palmar and plantar region are brown and have salmon-colored tubercles. The iris is black (Acosta-Galvis et al. 2006).

In preservative, the dorsal and lateral surfaces of the body and the exposed surfaces of the forelimbs, and hind limbs are brown. The spots that are white in life are cream in preservative. The flank is light brown. The hidden surfaces, groin, and anterior and posterior thighs are brown. The ventral surfaces, gular, and chest that ranged from brown to black in life are orange in preservative, but for some males it turns cream. The belly and ventral surfaces of the thighs are orange. The irregular spots become brown. The palmar and plantar region are brown with cream-colored tubercles (Acosta-Galvis et al. 2006).

Individuals can vary slightly in coloration. One adult female has cream-colored spicules on the trunk and dorsal surface of the thigh. Some specimens have tubercles with cream-colored pustules on the postorbital regions. Some have smooth large flattened tubercles with dispersed spicules on the trunk flanks. Additionally, one female has evenly distributed spicules on the dorsal surfaces. The species also displays sexual dimorphism. Females are larger, have smoother skin, and are more slim than males. Males have shorter, stronger limbs, thicker forearms, and have more warts and tubercles on the skin (Acosta-Galvis et al. 2006).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Colombia


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

Atelopus mittermeieri has been found in three localities of Colombia: at the periphery of the Guanentá Alto-Río Fonce Flora and Fauna Sanctuary; in the vicinity of Hacienda El Establo, 2 km from the mouth of the Cañaverales river and 70 km from the Duitama to Charalá highway; and in the municipality of Gámbita, approximately 55 - 56 km from the town of Charalá. The species lives in the high Andean forests of Colombia that neighbor the Paramo de la Rusia. The tree canopy reaches up to 10 m in height and the shaft has many mosses and epiphytes. The dominant vegetation is oak groves of the species Quercus humboldtii. On the top of the slopes, it is replaced with Quercus colombiana and stilt palms of the species Catoblastos andinus. The temperature range is 11 - 25℃. Rainfall does not get above 2000 mm. There are two rainy seasons, one from April to June and the other from September to November. The latter has more rainfall (Acosta-Galvis et al. 2006).

Life History, Abundance, Activity, and Special Behaviors

Atelopus mittermeieri is active during the day. It can be found moving between rocks, swimming in water channels and permanently flowing streams, and in moderately sloping areas of the Andean jungle (Acosta-Galvis et al. 2006).

Breeding activity has been observed in July with the breeding season occurring the summer after the rainy season. Calls have been heard in May and August (Acosta-Galvis et al. 2006).

One female was recorded to contain 393 cream-colored eggs with diameters ranging 1.46 - 2.01 mm (Acosta-Galvis et al. 2006).

Tadpoles have been observed in March, April, and July during the day in a 3 km stretch of a river with an elevation ranging 2250 - 2750 meters above sea level. Larvae of most developmental stages avoided waterfalls, strong currents, and stagnant pools of water on stream banks. Most were observed in backwaters of rivers. The temperature of the water ranged between 9 - 14℃. The water is oxygen rich with a pH of 6 (Acosta-Galvis et al. 2006).

Trends and Threats

Atelopus mittermeieri is considered “Endangered” and its population is assumed to be decreasing. Batrachochytrium dendrobatidis (Bd) has been found in the known surviving population of this species but live specimens have not shown clinical symptoms of chytridiomycosis. Saprolegnia ferax, a fungus that likely comes from rainbow trout, has been found in Atelopus mittermeieri, and could be another reason for its decline. Predation by introduced trout is another potential threat. The remaining possible threats include stream water level fluctuations and pollution from agriculture, and mining of gold, platinum, and copper (IUCN 2017).

Possible reasons for amphibian decline

Intensified agriculture or grazing
Local pesticides, fertilizers, and pollutants
Long-distance pesticides, toxins, and pollutants
Predators (natural or introduced)
Climate change, increased UVB or increased sensitivity to it, etc.


The species authority is: Acosta-Galvis, A., Rueda, J.V., Velásquez, A. A., Sánchez S. J., Peña, J. A. (2006). “Descubrimiento de una nueva especie de Atelopus (Bufonidae) para Colombia: ¿Una luz de esperanza o el ocaso de los sapos arlequines?” Rev. Acad Colomb. Cienc. 30 (115): 279-290.

Osteological characteristics were used to determine that Atelopus mittermeieri is sister to the clade composed of A. muisca and A. lozanoi. Together, these species form a clade that is sister to A. marinkellei (Noriega Noriega 2006).

The species epithet, “mittermeieri”, comes from Dr. Russell Alfred Mittermeier, an American herpetologist who has greatly contributed to environmental conservation (Acosta-Galvis et al. 2006).


Acosta-Galvis, A., Rueda, J.V., Velásquez, A. A., Sánchez S. J., Peña, J. A. (2006). “Descubrimiento de una nueva especie de Atelopus (Bufonidae) para Colombia: ¿Una luz de esperanza o el ocaso de los sapos arlequines?” Rev. Acad Colomb. Cienc. 30 (115): 279-290.

IUCN SSC Amphibian Specialist Group. 2017. “Atelopus mittermeieri”. The IUCN Red List of Threatened Species 2017: e.T136033A49538834. Downloaded on 13 November 2020.

Noriega Noriega, P. (2006). “Relación de parentesco entre cuatro especies del género Atelopus (anura: bufonidae) de alta montaña colombiana, basada en caracteres osteológicos” [Unpublished bachelor's thesis]. Pontifical Xavierian University, Bogotá, Colombia.

Originally submitted by: Kira Wiesinger (first posted 2020-12-03)

Edited by: Ann T. Chang (2020-12-05)

Species Account Citation: AmphibiaWeb 2020 Atelopus mittermeieri <> University of California, Berkeley, CA, USA. Accessed Jun 23, 2021.

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Citation: AmphibiaWeb. 2021. <> University of California, Berkeley, CA, USA. Accessed 23 Jun 2021.

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