Pristimantis pramukae, Zumel & Buckley & Ron, 2022

Zumel, Daniel, Buckley, David & Ron, Santiago R, 2022, The Pristimantis trachyblepharis species group, a clade of miniaturized frogs: description of four new species and insights into the evolution of body size in the genus, Zoological Journal of the Linnean Society 195 (1), pp. 315-354 : 332-337

PRISTIMANTIS PRAMUKAE SP. NOV.

( FIGS 10–14 ; TABLES 2 AND 3 )

Z o o b a n k r e g i s t r a t i o n: u r n: l s i d: z o o b a n k. org:act: 82CD48C8-6AB1-4BEA-91E2-AD3E5AD6CDF3

Holotype ( Figs 10 , 11 ): QCAZ 68549 (field no. SC-PUCE 59107 ), adult female from Ecuador, Provincia Morona Santiago, Cantón Gualaquiza, Parroquia Bomboiza , on the buffer zone of El Quimi Biological Reserve , tepui plateau on the eastern side of the Quimi River (3.5184º S, 78.3919º W), 1991 m a.s.l., collected by Darwin Núñez, Eloy Nusirquia, Alex Achig, and Ricardo Gavilanes on 4 July 2017.

Paratypes (34: 19 males, 13 females, two juveniles): Ecuador: Provincia Morona Santiago: Buffer zone of El Quimi Biological Reserve, tepui plateau on the eastern side of the Quimi River , QCAZ 68547 and QCAZ 68580 adult males (3.5184º S, 78.3919º W), 1991 m a.s.l. ; QCAZ 68559 , subadult female (3.5180º S, 78.3980º W), 2055 m a.s.l. ; QCAZ 68572 , subadult male (3.5191º S, 78.3893º W), 2003 m a.s.l. ; QCAZ 68574 , subadult male (3.5196º S, 78.3844º W), 2074 m a.s.l. ; QCAZ 68579 , subadult female (3.5197º S, 78.3849º W), 2074 m a.s.l. ; QCAZ 68591 , subadult male (3.5188º S, 78.3802º W), 2132 m a.s.l. ; QCAZ 68595 , adult female (3.5189º S, 78.3839º W), 2035 m a.s.l. ; QCAZ 68610 , adult male (3.5181º S, 78.3975º W), 2032 m a.s.l. ; QCAZ 68613 , adult male (3.5185º S, 78.3921º W), 1980 m a.s.l. ; QCAZ 72588 and QCAZ 72592 , juveniles (3.5182º S, 78.3913º W), 1994 m a.s.l. ; QCAZ 72589 , QCAZ 72593 , QCAZ 72605 and QCAZ 72610–72612 , adult males (3.5182º S, 78.3913º W), 1994 m a.s.l. ; QCAZ 72590–72591 , QCAZ 72606–72608 and QCAZ 72620 , adult females (3.5182º S, 78.3913º W), 1994 m a.s.l. ; QCAZ 72617 , subadult male (3.5182º S, 78.3913º W), 1994 m a.s.l. ; QCAZ 72600–72601 , subadult females, and QCAZ 72602 , adult male (3.5182º S, 68.3969º W), 2010 m a.s.l. ; QCAZ 72604 , adult female (3.5187º S, 78.3729º W), 2165 m a.s.l. ; QCAZ 72613 , subadult male (3.5198º S, 78.3902º W), 2059 m a.s.l. ; QCAZ 72614 , subadult male, and QCAZ 72615 , adult female (3.5197º S, 78.3904º W), 1995 m a.s.l. ; QCAZ 72618 , adult male (3.5157º S, 78.4106º W), 2017 m a.s.l. ; QCAZ 72619 , adult male (3.5193º S, 78.3869º W), 2028 m a.s.l. Collected by D. Almeida, D. Núñez, E. Nusirquia, A. Achig , R. Gavilanes and M. Moretta on 12–20 April 2018 and 4–10 July 2017 .

Suggested common name: English: Bomboiza rain frog. Spanish: cutín de Bomboiza.

Diagnosis ( Figs 10–14 ): A species of Pristimantis characterized by the following combination of characters: (1) dorsal skin smooth to shagreen; scapular region usually with two scapular subconical tubercles and a low \ /-shaped scapular fold; dorsolateral folds absent; ventral skin weakly areolate on throat and chest, coarsely areolate on belly and posteroventral surface of thighs; discoidal fold distinct; (2) tympanic annulus distinct and externally visible through skin, its upper margin covered by low supratympanic fold; tympanic membrane present but hidden by skin; one or two postrictal conical tubercles; (3) snout short to moderate in length, rounded to subacuminate in dorsal view and rounded to protruding in profile; (4) upper eyelid with one distinct subconical tubercle on its posterolateral quadrant, and several pustules spread over all their surface; (5) cranial crests absent; (6) vocal slits and nuptial pads absent; (7) Finger I shorter than Finger II; discs of digits expanded, rounded; (8) fingers without lateral fringes; (9) low and subconical ulnar tubercles; (10) heel bearing one to few low subconical tubercles; inner tarsal fold diffuse; subconical outer tarsal tubercles; (12) narrow lateral fringes on toes; basal toe webbing, most distinctive between Toe IV and Toe V; Toe V slightly longer than Toe III; toe discs as large as those on fingers; (13) in life, dorsum brown to dark brown usually with a W-shaped paler mark in the scapular region; head bearing a pale cream interorbital bar and sides of head brown with darker labial bars; flanks with the same colour of the dorsum, with or without several diffuse dark brown diagonal stripes, which also extend along dorsal surfaces of limbs; surfaces adjoining the outline of these diagonal stripes are generally paler and show white spots or flecks; venter brown with pale flecks and a few white spots, which may reach lower halves of flanks and head; a pale midventral stripe extends from the lower lip to the belly in those individuals having middorsal stripe; inconspicuous small red blotches may appear on upper groin and dorsal surface of thighs; groins pale brown with or without inconspicuous red blotches; iris copper; and (14) SVL in adult females from 18.27 to 21.03 mm (mean = 19.43 mm; N = 9), in adult males from 14.09 to 16.80 mm (mean = 15.09 mm; N = 13; Tables 2 and 3 ).

Comparisons with other species: In this section, coloration refers to live individuals unless otherwise mentioned. Pristimantis pramukae is most similar to some congeneric species of the P. trachyblepharis species group, especially to P. nanus in its short snout and the W- shaped pale marks in the scapular region. Pristimantis ventristellatus can also be confounded with P. pramukae because both have similar dorsal colorations and a dark venter with scattered clear spots and pale flecks ( Figs 13 , 23 ). However, P. nanus (SVL = 11.04–12.46 mm in adult males; 14.08– 14.82 mm in adult females) is smaller than P. pramukae (SVL = 14.09–16.80 mm in adult males; 18.27–21.03 mm in adult females; Tables 2 and 3 ) and has less expanded discs on fingers and toes. On P. ventristellatus , the clear ventral spots are more numerous than in P. pramukae , and the venter is noticeably darker. In addition, dorsal surfaces of P. pramukae are usually less tuberculate than that on P. ventristellatus .

Outside the P. trachyblepharis group, P. pramukae is similar to P. exoristus ( Duellman & Pramuk, 1999) by having a small size and a W- shaped mark in the scapular region. However, in P. exoristus , that mark is dark, and in P. pramukae it is paler than the background ( Fig. 10A ). Additionally, in P. exoristus the snout is moderately long (in P. pramukae it is short) and Toe V is much longer than Toe III (Toe V slightly longer than III in P. pramukae ).

Description of the holotype: Adult female (QCAZ 68549). Measurements (in mm): SVL 19.83; tibia length 10.22; foot length 8.69; head length 7.34; head width 6.41; interorbital distance 2.03; width of upper eyelid 1.77; internarial distance 1.78; eye–nostril distance 2.37; eye diameter 2.57; tympanum diameter 0.75. Colour of the holotype in life and in preservative is shown in Figures 10 and 11 , respectively.

Head ( Figs 10 , 11A, B ): Longer than wide, wide as body; snout short, rounded in dorsal and lateral views; canthus rostralis distinct, concave in dorsal view, rounded in profile; loreal region concave; tympanic annulus distinct, its upper margin covered by low supratympanic fold; tympanic membrane present but hidden by skin; one conical postrictal tubercle; posterolateral quadrant of eyelid bearing a single subconical tubercle; skin on throat areolate; dentigerous processes of vomer oblique, posterior to choanae, broadly separated from each other; choanae not concealed by palatal shelf of maxilla; tongue longer than wide, not notched posteriorly, posterior threefifths not adherent to the mouth floor.

Dorsum and venter ( Figs 10 , 11A, B ): Dorsal skin smooth; scapular region with low \ /-shaped scapular folds and a pair of posteromedial subconical tubercles; dorsolateral folds absent; many pustules on cloacal region; skin on chest weakly areolate, belly coarsely areolate; discoidal fold distinct.

Forelimbs ( Fig. 11C ): Low and subconical ulnar tubercles; Finger I shorter than Finger II; discs expanded, rounded; all fingers having ventral pads surrounded by circumferential grooves; palmar tubercles well defined, outer palmar tubercle bifid, approximately twice the size of the ovoid thenar tubercle; high subarticular tubercles; low hyperdistal subarticular tubercles; supernumerary tubercles at base of fingers; fingers lacking lateral fringes; basal webbing slightly noticeable.

Hindlimbs ( Fig. 11D ): Heel bearing one low subconical tubercle; outer surface of tarsus with low subconical tubercles; inner tarsal fold absent; Toe V slightly longer than Toe III; discs expanded and rounded, except those on Toe III and Toe IV of the right foot, which are expanded and elongate acuminate; discs nearly as large as those on fingers; all toes having ventral pads surrounded by circumferential grooves; subarticular tubercles well defined, as high as those on hands; low hyperdistal subarticular tubercles; numerous indistinct supernumerary tubercles; enlarged inner metatarsal tubercle, approximately five times the size of the small, rounded and high outer metatarsal tubercle; narrow lateral fringes; basal webbing, most distinctive between Toe IV and Toe V; skin on posteroventral surfaces of thighs coarsely areolate.

Variation: There is no appreciable mean uncorrected genetic p- distance between the three individuals of P. pramukae with available sequences for the 16S gene. In the type series, adult males (SVL = 14.09– 16.80 mm) are between 8.05 and 33.01% smaller than adult females (SVL = 18.27–21.03 mm). Below we list character states distinct from those described in the holotype, followed by an example. Colour variation in life and in preservative is shown in Figures 12 to 14.

Head ( Figs 12–14 ): Snout moderate in length (QCAZ 72591). Snout subacuminate in dorsal view, protruding in profile (QCAZ 68572). Canthus rostralis distinct (QCAZ 68613), angular in profile (QCAZ 72607). One subconical postrictal tubercle (QCAZ 68580); two subconical tubercles (QCAZ 72614). Upper eyelid with two subconical tubercles (QCAZ 68579); one conical tubercle and three subconical tubercles (QCAZ 72590). Dentigerous processes of vomer barely noticeable (QCAZ 68595).

Dorsum and venter ( Figs 12–14 ): Cream middorsal stripe extending from snout to cloacal region in 40% of the paratypes (N = 14). Dorsal skin shagreen (QCAZ 72611); shagreen with scattered pustules (QCAZ 72591). Scapular folds diffuse (QCAZ 72615). Two pairs of scapular subconical tubercles along the scapular fold, anterolateral and posteromedial in the scapular region (QCAZ 72606); two posteromedial conical tubercles in the scapular region (QCAZ 68591). Cloacal subconical tubercles (QCAZ 72620). Two lateral folds on each flank (QCAZ 72605). Diffuse dorsolateral folds (QCAZ 68613).

Forelimbs ( Fig. 14 ): Antebrachial tubercle distinct (QCAZ 68613). Narrow lateral fringes (QCAZ 72610).

Hindlimbs ( Fig. 14 ): Heel tubercle and outer tarsal tubercles prominent (QCAZ 72592).

Distribution, natural history and conservation status: This species is only known from a single locality in the buffer zone of El Quimi Biological Reserve, in Morona Santiago Province, Ecuador, between 1991 and 2132 m a.s.l. ( Fig. 3 ). Its natural region is Eastern Montane Forest. Both localities are on a limestone tepui plateau on the eastern side of the Quimi Valley. The new species lives in forest ( Fig. 4 ) composed of thin, scattered trees 10–15 m tall, shrubby vegetation up to 5 m sometimes mixed with a few palms and soils with cushioned consistency, covered by mosses, roots and terrestrial bromeliads. This type of soil is locally known as bamba and is characteristic of limestone tepui formations. The easternmost locality was at a distance of about 1 km from the nearest disturbed area (pastureland), suggesting that P. pramukae may have some level of resistance to human-generated environmental disturbances. By day, individuals were found at ground level. At night, they occur perching up to a height of 300 cm on leaves, branches, bromeliads and mosses. One amplectant couple was found on a branch 130 cm above the ground, near a stream, at 9: 36 p. m. on 16 April 2018. The height above the ground and the substrate on which the amplecting couple was found is similar to several individuals found at night, compared to those collected during the day, which may suggest that it is a species with nocturnal activity. The Extent of Occurrence of this species is 0.601 km 2, and the Area of Occupancy 12 km 2. However, there are still unexplored adjacent zones that could represent potential distribution areas for this species. Therefore, we assign P. pramukae to the Data Deficient Red List Category ( IUCN 2021). The type locality is <1 km from the border with Peru. Therefore, its presence in Peru is almost certain.

Etymology: The specific epithet pramukae is a noun in the genitive case and is a matronym dedicated to Jennifer B. Pramuk, who, in collaboration with William E. Duellman, made one of the most influential reviews of Peruvian Pristimantis , including the description of 18 new species. Several of those species inhabit the Cordillera del Cóndor, near the type locality of P. pramukae .

Figures

Figure 3. Distribution of Pristimantis trachyblepharis species group. Locality information for examined specimens is shown in Supporting Information, Table S2. UCS: Unconfirmed Candidate Species. Elevations are indicated in metres above sea level.

Figure 4. Land coverage in the Ecuadorian localities where individuals of the eight described species of the Pristimantis trachyblepharis species group were found. Land coverage shapefile was downloaded from Ministerio del Ambiente y Agua of Ecuador, at http://ide.ambiente.gob.ec/mapainteractivo. Locality information for examined specimens is shown in Supporting Information, Table S2.

Figure 10. Photographs in live of the holotype of Pristimantis pramukae (QCAZ 68549; adult female, SVL 20.15 mm). A, dorsal view; B, lateral view; C, frontal view; D, ventral view.

Figure 11. Photographs of the holotype of Pristimantis pramukae (QCAZ 68549; adult female, SVL 19.83 mm) in preservative. A, dorsal view; B, ventral view; C, ventral view of the right hand; D, ventral view of the left foot.

Figure 12. Colour variation in life individuals of Pristimantis pramukae in dorsolateral view. A, QCAZ 68547 (adult male, SVL 14.78 mm); B, QCAZ 72608 (adult female, SVL 18.47 mm); C, QCAZ 72588 (juvenile, SVL 9.59 mm); D, QCAZ 72591 (adult female, SVL 19.91 mm); E, QCAZ 72617 (subadult male, SVL 13.14 mm); F, QCAZ 68591 (subadult male, SVL 13.18 mm).

Figure 13. Colour variation in life individuals of Pristimantis pramukae in ventral view. A, QCAZ 72591 (adult female, SVL 19.91 mm); B, QCAZ 72608 (adult female, SVL 18.47 mm); C, QCAZ 72588 (juvenile, SVL 9.59 mm); D, QCAZ 68591 (subadult male, SVL 13.18 mm); E, QCAZ 72617 (subadult male, SVL 13.14 mm); F, QCAZ 68547 (adult male, SVL 14.78 mm).

Figure 14. Colour variation in preserved individuals of Pristimantis pramukae: 1, dorsal views; 2, ventral views. A, QCAZ 72604 (adult female, SVL 18.58 mm); B, QCAZ 72606 (adult female, SVL 21.03 mm); C, QCAZ 72591 (adult female, SVL 19.91 mm); D, QCAZ 72620 (adult female, SVL 19.53 mm); E, QCAZ 72611 (adult male, SVL 15.13 mm); F, QCAZ 68580 (adult male, SVL 15 mm); G, QCAZ 68574 (subadult male, SVL 12.77 mm); H, QCAZ 72588 (juvenile, SVL 9.59 mm).

Figure 23. Colour variation in life individuals of Pristimantis ventristellatus in ventral view.A, QCAZ 69245 (adult male, SVL 16.46 mm); B, QCAZ 69263 (adult female, SVL 18.62 mm); C, QCAZ 69273 (adult male, SVL 15.41 mm); D, QCAZ 69318 (adult female, SVL 22.02 mm); E, QCAZ 69365 (adult female, SVL 20.85 mm); F, QCAZ 69368 (adult male, SVL 15.16 mm).