Pristimantis ferwerdai, Amézquita & Suárez & Palacios-Rodríguez & Beltrán & Rodríguez & Barrientos & Daza & Mazariegos, 2019

Amézquita, Adolfo, Suárez, Gustavo, Palacios-Rodríguez, Pablo, Beltrán, Iván, Rodríguez, Camilo, Barrientos, Lucas S., Daza, Juan M. & Mazariegos, Luis, 2019, A new species of Pristimantis (Anura: Craugastoridae) from the cloud forests of Colombian western Andes, Zootaxa 4648 (3), pp. 537-548 : 541-545

Pristimantis ferwerdai , sp. nov.

Figure 4 . Table 3 .

Holotype. An adult male ( ANDES-A 3879 ) collected on August 2, 2016, by Gustavo Suárez and Luis Mazariegos in the type locality: Mesenia-Paramillo Nature Reserve (5.52 N, - 75.89 W, 2,050 m.a.s.l.), south of the Municipality of Jardín , Department of Antioquia, and about 90 km southwest of the city of Medellín, Colombia.

Paratypes. Six adults (four males; ANDES-A 3874–78 ) and (two females; ANDES-A 3880–81 ) collected at the type locality and time, during the same field trips, along with the holotype .

Etimology. We propose the specific epithet ferwerdai as a patronym to honor of Willem Ferwerda, for his valuable work in the conservation of tropical ecosystems throughout Asia, Africa and South America. In particular, for his generous professional and personal contributions to the protection of cloud forests in Colombian nature reserves, which directly benefited the species we describe here.

Definition and diagnosis. Pristimantis ferwerdai sp. nov. is a medium-sized frog (SVL 23.7 ± 1.76 mm; Table 3 ), which we assign to the family Craugastoridae based on the terminal position obtained in our phylogenetic analyses ( Fig. 2 ), as well as on the following combination of morphological traits: all the specimens we observed (above 25) lacked webbed fingers and large external glands; all digit tips expanded, and tympanic membranes easily recognizable to the naked eye. Although phenotypic synapomorphies are unknown for Pristimantis ( Padial et al. 2014) , we assign the new species to this genus based on characteristic phenotypic traits of Pristimantis , including T-shaped terminal fingers, toes without membranes, and Toe V longer than Toe III; this placement is strongly supported by the molecular available evidence: P. ferwerdai sp. nov. is nested exclusively within Pristimantis species in our best phylogenetic hypothesis ( Fig. 2 ).

Pristimantis ferwerdai sp. nov. can be diagnosed by the following combination of morphological characters: (1) smalls conical tubercles that populate the dorsal and dorsolateral skin; (2) two dorsal folds which extend up to 2 / 4 of the dorsal surface, shaped like an hourglass or inverted brackets; (3) the ventral surface areolate; (4) dorsolateral folds absent; (5) paravertebral folds present; (6) postrical tubercles absent; (7) tympanum superficial, tympanic annulus prominent, round, corresponding to 1 / 4 of eye length; (8) supratympanic folds absent; (9) Canthus rostralis round, short snout, rounded in dorsal and lateral view; (10) upper eyelid with a prominent conical tubercle and some smalls tubercles around; (11) cranial crests absent; (12) mandibular tubercles absent; (13) males with vocal slits and subgular vocal sac; (14) ulnar tubercle prominent and subconical present; (15) tarsal tubercle prominent surrounded by small subconical tubercles; (16) finger I slightly shorter than II, expanded discs of the fingers II, III, IV; (17) manual fingers with lateral fringes; (18) two oval inner metatarsal tubercles; (19) toes with lateral fringes and expanded discs; and (20) paracloacal tubercle present; (21) posterior surfaces of thighs are cream with brown spots, sometimes suffusing with the black and white pattern of the ventral surface; (22) iris bronze to dark brown with a horizontal medial and reddish band, and often a reticulate pattern.

Pristimantis ferwerdai sp. nov. can be distinguished from most other Pristimantis species from the Andes of Colombia and Ecuador by the combination of dorsal coloration in life, an intergradation of green, lime-green or greenish brown blotches on a generally dark (black to dark brown) background, and the prominent conical tubercles on eyelids, heels and outer edge of tarsus ( Figs. 4 , 5 ). Two Colombian ( P. calcaratus and P. kelephus ) and two Ecuadorian species ( P. llanganati and P. mutabilis ) look externally similar to P. ferwerdai sp. nov.; they are dorsally green or greenish and they bear conical tubercles and spicula (that may actually disappear in P. mutabilis but not in our several-weeks captive P. ferwardae sp. nov.), yet all of them lack the pair of hourglass-shaped dorsal folds. The phylogenetically closest species to date, P. satagius , also lacks the dorsal folds, has indistinct dorsolateral folds and, in addition, is dorsally dark brown in coloration whereas ventrally is cream with heavy brown reticulation ( Lynch, 1995). In addition, none of these species exhibit the characteristic ventral (from the gular region to the ventral surface of the limbs) and inguinal coloration of P. ferwerdai sp. nov. white bands/blotches against a predominantly black background ( Fig. 5 ). The ventral coloration in those species is known to be light brown in P. mutabilis or brown in P. kelephus , with very poorly defined patterning. The new species also present vocal slits, which are absent in P. llanganati and not described in the other species. Conversely, P. ferwerdai sp. nov. lack the postrical tubercles that are present in P. calcaratus , P. kelephus , and the X-shaped (sometimes rhomboidal) brown or reddish brown middorsal mark, present in P. llanganati . Lastly, P. ferwerdai sp. nov. can also be easily distinguished from the syntopic P. erythropleura , which has similar dorsal appearance but exhibits whitish non-patterned ventral coloration in and conspicuous red-orange-yellow inguinal flash marks.

Description of the holotype ( Fig. 4 ). An adult male, 23.4 mm in snout-vent length (SVL). Head longer than wide, as narrow as the body; upper eyelid with one to five conical tubercles, one of which is considerably higher than the other ones; head width 39.7% of SVL and head length 44.0% of SVL; moderate snout (distance from eye to nostril 14% of SVL), rounded in dorsal and lateral views; eye diameter larger than eye-nostril distance; nostrils directed anterolaterally; canthus rostralis weakly concave in profile; cranial crests absent; tympanic membrane distinct; vomerine odontophores low, oblique in outline; skin on dorsum finely shagreen with interspersed low tu- bercles; dorsal hourglass shaped folds present; skin of throat and venter without warts; subarticular tubercles prominent, round; supernumerary palmar tubercles present; fingers bearing narrow lateral fringes; Finger I conspicuously shorter than Finger II (Finger I length 68% of Finger II length); all finger discs expanded, elliptical in shape. Tibia length 56.4% of SVL; femur length 24.4% of SVL; heel tubercle conical and large; tarsal tubercles small; toes bearing narrow lateral fringes; webbing absent; all other toe discs expanded.

Holotype measurements (in mm) Snout-to-vent length = 23.4, tibia length = 13.2, forelimb length = 5.7, femur length = 11.9, head length = 10.3, greatest head width = 9.3, distance from the eye to the nostril = 3.3, interorbital diameter = 4.1, distance from the tympanum to the eye = 1.1, diameter of the eye = 2.6 and diameter of the tympanum 1.3.

Coloration in life. Despite among-individuals variation in coloration, the dorsum generally intergrades green to lime-green against a predominantly dark background: black or dark brown ( Fig. 5 ). We kept animals in captivity for several weeks and did not detect appreciable changes in coloration. The pattern extends toward the dorsal surface of the limbs. Some individuals exhibit a mid-dorsal whitish line, as in many other species of Pristimantis . The flanks are predominantly dark, often crossed by oblique white bands or blotches, more evident toward the inguinal area. A nearly vertical whitish line below the eye and toward the mandible was evident in all individuals we examined. The ventral skin was generally very dark, more often black, mottled with white spots, blotches or white lines. In some individuals, the black and white coloration is suffused giving the general impression of brown, but the inguinal area remains patterned with a strong dark and white pattern. In most individuals, a darker triangle, with the tip towards the middle part of the body, is delimited by lighter areas ( Fig. 5 ). Eyes are copper with black pupils, often crossed by a horizontal reddish line.

Natural history. The species was found at night, in heavily forested areas, resting on moss or branches. Although no information is available on reproduction, the eggs are probably terrestrial and develop directly into froglets as in all known species of Pristimantis . The species was found syntopic with at least seven other species of Pristimantis in the same habitat. Among them, P. erythropleura was by far the most abundant species.

Conservation status. To date, the new species is only known from the Mesenia-Paramillo nature reserve within an area of less than 500 ha; no specimens of this species were found in the large herpetological collection at the Universidad de Antioquia. Due to the lack of information on its distribution, the relatively small area of the nature reserve, and the vulnerability of forests within this elevational belt, we tentatively list P. ferwerdai sp. nov. as Vulnerable (VU: B1a, biii; IUCN, 2001). This classification should nonetheless be considered provisional, since the cloud forests of this area are poorly explored.

Figures

FIGURE 2. Phylogenetic hypothesis based on mtDNA genealogy of the 16S gene. Nodal values indicate bootstrapping support. See Methods for further details.

FIGURE 4. Dorsolateral view (left), and ventral view of left hand and left foot (right) of the holotype of Pristimantis ferwerdai sp. nov. For scaling, we added 1-mm lines.

FIGURE 5. Variation among individuals in dorsal, inguinal (left) and ventral pattern in Pristimantis ferwerdai sp. nov. at the Mesenia-Paramillo Nature Reserve (northwestern Colombian Andes).

Tables

TABLE 3. Morphometric measurements (all in mm) taken on the type series of Pristimantis ferwerdai sp. nov. From left to right: Snout-vent length, Tibia length, Forelimb length, Femur length, Head length, Greatest head width, Distance from eye to nostril, Interorbital diameter, Distance from tympanum to eye, Diameter of the eye, and Diameter of the tympanum.

Code	SVL	TL	FL	FeL	HL	HW	EN	IOD	TE	DE	DT
ANDES-A3874	23	12.6	6.8	12.3	8.9	8.8	3.2	4	1.1	3.6	1.2
ANDES-A3875	25.5	12.9	6.3	12.6	10.8	9.4	3.4	4.2	0.9	3.5	1.2
ANDES-A3876	22.1	11.7	4.8	10.7	8.1	7.8	2.6	3.9	0.9	3.3	1.0
ANDES-A3877	24.9	13.3	6.0	12.6	9.6	9.4	3.6	4.1	1.1	3.3	1.0
ANDES-A3878	21.2	11.7	5.9	10.6	8.1	7.9	2.8	3.6	1.2	3.3	1.2
ANDES-A3879	23.4	13.2	5.7	11.9	10.3	9.3	3.3	4.1	1.1	2.6	1.3
ANDES-A3880	22.8	11.9	5.4	11.1	9.5	8.6	3.3	4.1	1.0	2.8	1.3
ANDES-A3881	26.4	14.9	6.5	13.4	10.2	10.5	3.8	4.3	1.2	3.4	1.1
Mean	23.66	12.76	5.91	11.9	9.45	8.96	3.26	4.04	1.05	3.23	1.18
SD	1.76	1.09	0.59	1.01	1.0	0.88	0.37	0.22	0.12	0.33	0.11