Description
Prismantis achupalla is a bromeliad-dwelling frog described from four adult males with a snout-vent length range of 10.0 - 12.8 mm. The head is longer than wide and narrower than the body. The snout is short and in the dorsal view, appears acuminate, while in the lateral view, it appears truncated. There are papillae on the rostrum. The lips of the amphibian are flat, not flared, and there are postrictal tubercles or ridges present. The slightly protuberant nostrils are located close to the snout. The canthus rostralis is rounded in the profile and weakly concave in the dorsal view. The loreal region is flat. The eyes are large. The eyelid, which is slightly less than three-quarters the interorbital distance, has two to three subconical or round tubercles. The tympanic membrane and annulus are distinct and slightly less than a quarter of the eye diameter. There is no supratympanic fold. The rugose skin consists of small tubercles on the head, dorsum, lateral sides, and dorsal surface of limbs. There are no dorsolateral, pectoral, or discoidal folds. The ventral and gular surfaces are areolate. There is a small ulnar tubercle, but the forearm otherwise does not have tubercles. There is a large, flat, bifurcated palmar tubercle with the inner lobe being much larger than the outer. The elongated thenar tubercle is half the size of the palmer tubercle. There are no supernumerary tubercles. The fingers have narrow lateral fringes and prominent subarticular tubercles that are oval in the ventral view and round in the lateral view. The relative finger lengths are III > IV > II > I and the fingers end in broadly expanded, elliptical pads that have well defined circumferential grooves. The tibia is slightly more than half the snout-vent length and the foot is about 40% of the snout-vent length. The heel does not have tubercles, but the outer surface of the tarsus does. The inner metatarsal tubercle is oval and more than twice as high as the conical, round outer metatarsal tubercle. There are also supernumerary tubercles on the plantar. The toes do not have narrow lateral fringes or basal webbing, but do have subarticular tubercles that are round and oval in the dorsal view. Like the fingers, the toes end in ventral pads with circumferential grooves. The relative length of adpressed toes is IV > V > III > II > I (Ttito and Catenazzi 2021).

DIAGNOSIS:

Pristimantis achupalla is morphologically similar to multiple species such as P. acuminatus, P. enigmaticus, P. galdi, P. lacrimosus (variable), P. limoncochensis, P. mendax, P. moro, P. olivaceus, P. omeviridis, P. padiali, P. pardalinus, P. pluvialis, P. rhodostichus, P. schultei, and P. tantanti. The characteristics that these species share include dorsolaterally compressed heads and bodies and papilla or tubercles on the rostrum. However, P. achupalla has a smaller snout-vent length, rugose skin that extends on to the hindlimbs, and larger tubercles on the upper eyelid. Seven other species are particularly similar in appearance. However, P. achupalla can be differentiated by the presence of a supratympanic fold in P. amaguanae, a smooth dorsum and lack of a dermal fold in P. bromeliaceus, smooth skin with a tarsal fold and no tubercles on the upper eyelid in P. enigmaticus, smooth skin without dorsolateral folds, but with a tarsal fold, and a lack of a tympanic membrane and annulus in P. limoncochensis, lack of tubercles on the upper eyelid in P. omevirdis, skin texture and coloration in P. schultei, and shagreen skin with elongated ulnar tubercles in P. tantanti (Ttito and Catenazzi 2021).

COLORATION:

In life, the dorsum of the frog has greenish-brown pigmentation. A dark brown interorbital bar is present, forming a triangular shape to the posterior. The canthus rostralis is dark greenish brown and the upper eyelids are dark green. The hind and forelimbs are green with the exception of oblique, brown, blurred bars. The throat and the ventrum have a pale green coloration. The iris has dark-brown reticulations on a bronze background. In preservative, The dorsal surface of the head is brown and the body is cream with slight dark brown areas around the scapulae. The interorbital bar is brown, the canthus is dark brown, and the upper eyelids are a dark bluish color. The transverse hindlimb bars remain dark. The ventral surface of the body is cream while the ventral surfaces of the thighs, plantar, palms, and digits become pale green. The tubercles are darker gray. The iris becomes dark gray (Ttito and Catenazzi 2021).

VARIATION:

There are variations in coloration and skin texture. Some individuals have interorbital bars that range from a brown hue to a cream-like color. Some individuals have fainter brown barring on the hind limbs. Scattered tubercles on the dorsal surfaces can be found on some individuals, while others just have rough skin texture. Sexual dimorphism could not be assessed at the time of the species description as no female specimens were collected (Ttito and Catenazzi 2021).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Peru

View distribution map in BerkeleyMapper.

The species was found along the Macusani-San Gaban road in a relictual montane cloud forest along the Cordillera de Carabaya, in the southern Peruvian department of Puno along a tributary of the Inambari River. The habitat where P. achupalla was found was near a highway that connects the Peruvian Altiplano to the Amazon rainforest and the interoceanic highway between Peru and Brazil and was accessed via a high-voltage power line maintenance road (Ttito and Catenazzi 2021).

Life History, Abundance, Activity, and Special Behaviors
Pristimantis achupalla was found in epiphytic bromeliads on trees that overhang a maintenance trail for high-voltage power lines through a relictual montane cloud forest in the late afternoon to early evening. These findings indicate that the species is a bromeliad specialist (Tito and Catenazzi 2021).

Other species found in the area included what is presumed to be Gastrotheca testudinea, Pristmantis platydactylus, Psychrophrynella glauca and Noblella thiuni (Tito and Catenazzi 2021).

Trends and Threats
At the time of the species description, the authors recommended a conservation status of “Data Deficient” because of limited information on geographic range, population abundance. However, there are known threats of deforestation and habitat loss due to small-scale agriculture, hydropower, road construction, and other large-construction projects in the upper Ollachea Valley (Ttito and Catenazzi 2021).

Possible reasons for amphibian decline

General habitat alteration and loss
Habitat modification from deforestation, or logging related activities
Intensified agriculture or grazing
Dams changing river flow and/or covering habitat

Comments

PHYLOGENETIC RELATIONSHIPS:

Maximum Likelihood analysis of 16S rRNA found that P. achupalla is most closely related to an undescribed species, and together they are sister to P. amaguanae. The next most closely related species is P. moro (Ttito and Catenazzi 2021).

ETYMOLOGY:

The species epithet, “achupalla” is a noun in the Quechua language meaning “bromeliads”, and is in reference to the species’ use of bromeliads microhabitats (Ttito and Catenazzi 2021).

References

Ttito, A. and Catenazzi, A. (2021). "Pristimantis achupalla sp. n., a new minute species of direct-developing frog (Amphibia, Anura, Strabomantidae) inhabiting bromeliads of the montane forest of the Amazonian Andes of Puno, Peru." PeerJ 9, e11878 [link]

Species Account Citation: AmphibiaWeb 2023 Pristimantis achupalla <https://amphibiaweb.org/species/9438> University of California, Berkeley, CA, USA. Accessed Nov 21, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 21 Nov 2024.

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