Fifty years after: A taxonomic revision of the amphibian species from the Ecuadorian biodiversity hotspot Abra de Zamora, with description of two new Pristimantis species

Holotype. KU 166058, an adult male, found in Abra de Zamora, Provincia Zamora- Chinchipe, Ecuador, 2850 m, on 8 March 1975 by Dana K. Duellman. Paratype. KU 166057, an adult female topotype, obtained on 7 March 1975. Diagnosis. Pristimantis percultus is a medium sized species distinguished by the following combination of traits: (1) skin on dorsum and flanks pustulated, covered with large flat warts or pustules (in life the pustulated skin texture is more evident); skin on venter coarsely areo- late; discoidal fold weak; dorsolateral folds absent; (2) tympanic annulus evident and tympanic membrane differentiated, its length about 47% of the length of eye; supratympanic fold pres- ent; (3) snout subacuminate in dorsal view, rounded in profile, with pointed tip; canthus ros- tralis weakly concave in dorsal view, rounded in profile; (4) upper eyelid bearing one larger and several small tubercles (trait more visible in life), about 74% IOD in females and 87% IOD in males; barely visible, low cranial crests present; (5) dentigerous processes of vomers promi- nent, oblique, triangular, separated medially by distance lower than the width of processes; each processes bearing 4 to 8 teeth; (6) males lacking vocal sac and vocal slits; (7) Finger I shorter than Finger II; discs on fingers broadly expanded, rounded; circumferential grooves present; fingers bearing narrow lateral fringes; (8) subarticular tubercles prominent, round, non-conical; supernumerary palmar tubercles present; palmar tubercle bifid, partially divided

into a larger (inner) and a smaller (outer) tubercles; thenar tubercle elliptical, smaller than the palmar tubercle, but larger than either palmar tubercles (inner or outer); (9) small, inconspicu- ous, ulnar tubercles present (trait more visible in life); (10) heel with one large and several smaller rounded tubercles; outer edge of tarsus with a row of large conical tubercles; inner tar- sal tubercles coalesced into a short tarsal fold; (11) inner metatarsal tubercle broadly ovoid, about 4x ovoid, outer metatarsal tubercle; supernumerary plantar tubercles present; (12) Toe V much longer than Toe III; discs on toes broadly expanded, rounded, about same size as those on fingers; circumferential grooves present; toes bearing narrow lateral fringes; webbing basal; (13) in life, dorsum brown or beige with or without dark brown flecking and marbling or large white spots; lips sometimes with orange strips; venter cream with or without dark flecking; no markings in axilla, groin or on concealed limb surfaces; iris bronze with dense black reticulations; (14) SVL 30.1–38.2 mm in adult females (33.6 ± 4.15 SD, n = 3; [9]) and 29.8 mm in one adult male [9]. Variation. Morphometric variation is shown in Table 3. The coloration of female MUTPL 810 (Fig 24A) is similar with that of the holotype KU 166058, with the exception of the orange strips on the lips. Neither of the encountered specimens had the lips colored. The female MUTPL 812 (Fig 24B) had the similar large white spots bordered by dark brown borders like

the specimen KU 202427. The subadult MUTPL 811 (Fig 24C) had a peculiar coloration with dorsum light brown and flanks multicolored with yellow, green, brown and pinkish gray blotches. Also, this specimen was the only one that had dark interorbital bars. In all encoun- tered specimens the dorsum and especially the flanks pustulated texture it was very evident. Most of the pustules had the yellowish orange color similar with those of the holotype. Addi- tionally, all three specimens presented some scar-like wrinkles on their flanks (more evident in the case of MUTPL 812, Fig 24b). Advertisement call. Unknown. Distribution. Despite intensive searches carried out since 2016 we did not find any individ- uals in the type locality, Abra de Zamora. Pristimantis percultus was reported from Parque Nacional Podocarpus (Cajanuma sector) in 2010 [52], in a grass pa´ramo ecosystem [44], from about 12 km south to Abra de Zamora (Fig 23). We also encountered there in 2019. The spe- cies was recorded at an altitudinal range between 2850 and 3380 m a.s.l. in subpa´ramo and grass pa´ramo ecosystems. PLOS ONE Taxonomic revision of the amphibian species from Abra de Zamora PLOS ONE | https://doi.org/10.1371/journal.pone.0238306 September 10, 2020 43 / 59