Description
Pristimantis andinognomus is a very small frog, with males having a snout-vent length ranging from 10.0 - 14.5 mm and females 12.0 – 17.9 mm. The head is just as wide as the body. The snout is short and has a small tubercle at the very tip that is very rounded when viewed from above, and less rounded when viewed from the side. The nostrils are somewhat prominent, and point towards the sides of the back. The region between the eye and the snout on the side of the head is somewhat concave when viewed from the back, and rounded when viewed from the side. The region between the eye and the nostril is barely concave. It has round lips, and a round tympanum that is covered by a fold on its upper and lower sides. It has more minute tubercles on the right side of its mouth than on the left side. The skin on the back is granular, and it has folds on the sides of its back. The tubercles on the sides of the body are larger and more numerous than on the back. There is a conical tubercle on its sacrum. The skin on the underside has a minutely spotted pattern to it. There is a small tubercle on each ulna, and the outer tubercle on the palm is cleft. The subarticular tubercles are distinct, elliptical when viewed from the underside, and round when viewed from the side. The fingers are fringed laterally. Finger I is shorter than Finger II, and there is no other information available on the relative finger lengths. There are no nuptial pads on the fingers. The legs are slim, with a granular texture on the upper side of the thighs, and a spotted appearance on the underside of the thighs. There are two tapered tubercles on each heel, with the one towards the back being larger than the one towards the front. The toes are fringed laterally, have distinct pads on the underside, and lack webbing. The relative lengths of the toes are as follows, from shortest to longest: I < II < III < V < IV (Lehr and Coloma 2008).

Pristimantis andinognomus is easily distinguished from other Pristimantis frogs by size. This is the smallest Pristimantis species and is smaller than other frogs in where they occur. It can be further distinguished by the presence of dorsolateral and postocular folds, two large conical upper eyelid tubercles, scapular, sacral, and heel tubercles, tympanic membrane and annulus, and the absence of nuptial pads (Lehr and Coloma 2008).

In life, Pristimantis andinognomus has an iris that is brown and gold with fine black reticulations. There is a dark brown interorbital bar with a gray blotch at the anterior end. The upper lip has two dark brown bars below the eyes and a dark brown stripe above the tympanum. There are two black spots in the scapular region and dark brown flecks on the scapular and sacral regions. These flecks are surrounded by a pale grey. There is a pale grey band from the upper arm to mid of the lower arm. The legs have irregularly shaped bars of dark brown with black flecks. The flank has a dark brown diagonal band. The dorsum is shagreen (Lehr and Coloma 2008).

The preserved holotype has an iris that is dark grey. The sides of the head are greyish brown. The interorbital, supra-tympanic, flank, and arm bars remain dark brown. The black spots on the scapular region also remain. The cloacal region is dark brown. The throat is slightly darker than the other ventral surfaces. Fingers I and II are tan, and the others are brown. Toes I through IV are tan, and Toe V is dark brown. The dorsum is a pale grey-brown with brown blotches (Lehr and Coloma 2008).

Individuals may have dorsolateral folds that are pale grey in color. Some individuals may have a pale grayish brown back with a pale gray stripe running down the middle, others may have three pale brown stripes running down the length of the back. The conspicuousness of the tubercles and the folds may vary (Lehr and Coloma 2008).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Ecuador

View distribution map in BerkeleyMapper.

Pristimantis andinognomus can be found at an elevation from 2400 m to 2800 m. It is known from two distinct localities, Abra de Zamora, Ecuador and the southernmost border of Podocarpus National Park, Ecuador. The approximate distribution of this species consists of 620 km² between the two localities. It inhabits primary cloud forests and can be found 10 to 100 cm off the ground in vegetation at night (Lehr and Coloma 2008).

Life History, Abundance, Activity, and Special Behaviors
One gravid female was found with 10 large, unpigmented eggs and traces of both ants and mites within her stomach (Lehr and Coloma 2008).

Pristimantis andinognomus is thought to frequent leaf litter in search of food (Lehr and Coloma 2008).

Trends and Threats
There is currently no information on trends and threats.

Comments
The species authority is: Lehr, E., Coloma, L. A. (2008). "A minute new Ecuadorian Andean frog (Anura: Strabomantidae, Pristimantis)." Journal of Herpetology, 64(3), 354-367.

Pristimantis andinognomus forms a clade with P. colodactylus and P. caeruleonotus, two other small Pristimantis species that inhabit southern Ecuador and northern Peru (Lehr and Coloma 2008).

The specific epithet andinognomus means “Andean dwarf” (Lehr and Coloma 2008).

References

Lehr, E., Coloma, L. A. (2008). ''A minute new Ecuadorian Andean frog (Anura: Strabomantidae, Pristimantis).'' Journal of Herpetology, 64(3), 354-367.

Species Account Citation: AmphibiaWeb 2015 Pristimantis andinognomus <https://amphibiaweb.org/species/7224> University of California, Berkeley, CA, USA. Accessed Nov 26, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 26 Nov 2024.

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