Pristimantis chamezensis, Acosta-Galvis & Saldarriaga-Gómez & Ramírez & Vargas-Ramírez, 2020

Acosta-Galvis, Andres R., Saldarriaga-Gomez, Ana M., Ramirez, Beatriz & Vargas-Ramirez, Mario, 2020, A new Terrarana frog of genus Pristimantis from an unexplored cloud forest from the eastern Andes, Colombia, ZooKeys 961, pp. 129-156 : 129

Pristimantis chamezensis sp. nov. Figs 4 , 5 ; Table 4

Holotype.

IAvH-Am-10269 (field number ARA 5852. Figs 4 , 5 ) an adult female collected on 3 September 2010 by Andrés R. Acosta-Galvis, Beatriz Ramirez, José Pérez, Luis Daniel Prada, and Natalia Novoa.

Type locality

(Figs 1 , 2 ). Colombia, Casanare Department, Chámeza Municipality, vereda Centro Norte, Chámeza forest, Cerro Pan de Azúcar, eastern flank of the Cordillera Oriental, Colombia. 05°15'24.4"N, 072°53'51.6"W, 2140 m a.s.l.

Paratypes

(11) (Fig. 5 ; Table 4 ). IAvH-Am-10267, IAvH-Am-10270-10274, adult males; IAvH-Am-10275-10277, IAvH-Am-10282, adult females, collected on 13 November 2010 by Andrés R. Acosta-Galvis, Beatriz Ramirez, José Pérez, Luis Daniel Prada, and Natalia Novoa; same locality as the holotype.

Referred specimens.

IAvH-Am-10268, IAvH-Am-10278-10281, IAvH-Am-10283-10287, juveniles, same locality and date as paratypes.

Diagnosis

(Figs 4 - 7 ). A species of Pristimantis characterized by the following combination of morphological characters: (1) dorsal skin shagreen with scattered larger tubercles; dorsolateral folds absent; discoidal fold visible; skin on venter areolate. (2) Tympanic membrane and tympanic annulus present, its dorsoposterior border converges with supratympanic fold; its diameters are 35.6-56.0% of the eye diameter; small, barely visible, subconical postrictal tubercles. (3) Snout short, broadly rounded in dorsal view and rounded in lateral view; canthus rostralis sharp and concave. (4) Upper eyelid bearing one to three subconical tubercles, narrower than IOD. (5) Choanae small, subovoid; dentigerous processes of vomers prominent, oblique, and widely separated from each other, bearing 8 or 9 teeth. (6) Males with vocal slits; subgular vocal sac observable; nuptial pads not evident. (7) Finger I shorter than II, with discs expanded and rounded; bifid palmar tubercle. (8) Fingers bearing narrow lateral fringes. (9) Ulnar tubercles absent. (10) Tarsal tubercles present, subconical; heel tubercles present but nearly inconspicuous and conical. (11) Two metatarsal tubercles, with inner tubercle elongate, three times the length of the rounded and prominent outer tubercle; supernumerary plantar tubercles numerous, enlarged, and rounded. (12) Toes with lateral fringes and broad discs; toe V much longer than toe III (disc on toe III extends to the proximal edge of the medial subarticular tubercle on toe IV, disc on toe V extends beyond the distal edge of the penultimate subarticular tubercle on toe IV); webbing absent. (13) Dorsal surface pattern variable, with homogeneous color brown (with or without paravertebral line) or inverted V-shaped markings with dark brown blotches edged with pale cream; iris gray, medially reddish, with black reticulations; ventral surfaces cream-colored to light brown, finely peppered with irregular, diffuse, dark-brown reticulations or blotches; posterior surface of thighs brown; dark-brown labial bars present or absent; edge of the chin with irregular blotches of dark brown (Fig. 5 ). (14) apparently sexually dimorphic in size (Table 4 ), with an SVL in adult males 19.6-23.7 mm and 19.0-24.9 mm in adult females.

Species comparisons

(Figs 5 - 7 , Suppl. material 1). The new species is compared to other species of Pristimantis in the eastern slope of the Cordillera Oriental in the Orinoco basin of Colombia. The character states of the compared species are enclosed in parentheses. Pristimantis chamezensis is distinguished from P. carranguerorum by the absence of short dorsolateral folds in the scapular region (present); snout rounded in dorsal view (subacuminate; Fig. 6 ); the dorsum brown, with some lighter and diffuse reticulations (pale dorsolateral lines; Fig. 6 ); and subconical tubercles on the upper eyelid (absent). The new species differs from P. vilarsi (Melin, 1941) in having the posterior surfaces of the thighs brown in life (reddish); adult females smaller, SVL 19.0-24.9 mm (SVL 25.4-43.2 mm); and the snout broadly rounded in dorsal view (subacuminate). Pristimantis chamezensis can be easily confused with P. savagei by the presence of one to three subconical tubercles on the upper eyelid; however, it differs by the absence of ulnar tubercles (present); snout broadly rounded in dorsal view (subacuminate); and posterior surface of thighs brown in life (pale orange). Pristimantis chamezensis is distinguished from P. medemi by having subconical tubercles on the upper eyelids (absent); dorsal and ventral iris gray in life (Fig. 5 ), medially reddish, with black reticules (orange to yellow); and smaller size, SVL 19.6-26.4 mm (SVL 29.4-43.1 mm). Pristimantis chamezensis differs from P. anolirex (Lynch, 1983) (Fig. 6 ) in lacking dorsolateral folds (present on half of the body); ulnar tubercles absent (present and small; Fig. 7 ); and snout broadly rounded in dorsal view (subacuminate). Pristimantis chamezensis is distinguished from P. lynchi (Duellman & Simmons, 1977) in having the edge of the chin with irregular blotches (Fig. 4 ) of dark brown (uniformly brown); palmar tubercle bifid (elliptical); and snout broadly rounded in dorsal view (subacuminate). Compared to P. bogotensis (Peters, 1863) (Fig. 6 ), P. chamezensis has a prominent dentigerous process on the vomers, oblique and widely separated from each other (concealed in the palatine tissue); and broadly rounded snout in dorsal view (rounded). Pristimantis chamezensis differs from P. frater (Werner, 1899) (Fig. 6 ) in having a broadly rounded snout in dorsal view (acuminate); and toes IV and V with narrow discs (broader). Pristimantis chamezensis is distinguished from P. terrapacis Ospina-Sarria & Angarita-Sierra, 2020 by having subconical tubercles on upper eyelid and heel (absent) and webbing absent between the toes (basal webbing). Pristimantis chamezensis differ from P. ardilae Acevedo et al. 2020 by the absence of short dorsolateral folds in the scapular region (present); broadly rounded snout in dorsal view (subacuminate); and upper eyelid with subconical tubercles (without tubercles). Pristimantis chamezensis is distinguished from P. bowara in having the broadly rounded snout in dorsal view (subacuminate) and dorsal skin shagreen with scattered larger tubercles (smooth). Lastly, P. chamezensis that can be distinguished from P. nicefori (Fig. 6 ) in having the discs of the digits expanded (slightly expanded), snout broadly rounded in dorsal view (acuminate), and snout broadly rounded in lateral view (pointed).

Description of the holotype.

An adult female (Figs 4 , 5 ) with a snout-vent length (SVL) of 23.8 mm; the skin of cephalic region, dorsum, eyelids, lateral surfaces, and dorsal thighs shagreen with scattered larger tubercles; dorsolateral folds absent and discoidal folds visible; skin on venter areolate. Head length (HL), diagonally from the corner of mouth to tip of snout 10.4 mm; head width (HW) 9.8 mm, approximately equal to width of the body and 41.1% of the SVL. Snout broadly rounded in dorsal view (type F, sensu Duellman and Lehr 2009; Fig. 4 ) and rounded in lateral view (type A, sensu Duellman and Lehr 2009; Fig. 4 ); internarial distance (between center of naris) 2.9 mm; nostril moderately protuberant, directed dorsolaterally; canthus rostralis well defined; loreal region slightly concave; lips not prominent. Eye diameter (ED) from its posterior to anterior corner 3.3 mm; its length 73.3% of the ETS (distance between the anterior edge of the eye to the tip of snout); interorbital region wider than upper eyelid; the upper eyelid width (UEW) 55.2% of interorbital distance (IOD); upper eyelid bearing three smaller subconical tubercles (Figs 4 , 5 ); no cranial crests. Supratympanic fold low and short. Tympanic membrane and tympanic annulus present, small, and rounded (Figs 4 , 5 ), its dorsoposterior border converges with supratympanic fold; its diameter 1.1 mm and equivalent to 33% of eye diameter (ED). Choanae subovoid, not concealed by the palatal shelf of the maxillary arch; dentigerous processes of vomers prominent, nine teeth positioned posterior to level of choanae and widely separated from each other. Tongue rounded, its posterior border notched for half of its extension is adherent to the floor of mouth; teeth present on the maxillary arch.

Forelimbs of moderate size, forearm length 6.4 mm; ulnar tubercles absent. Hand length (HnL) 7.4 mm its length 31.0% of SVL. Palmar tubercle bifid, about two-thirds the length of oval thenar tubercle (Fig. 7 ). Supernumerary palmar tubercles present, rounded to elongated, and slightly elevated; subarticular tubercles large, round, and conical; fingers without lateral fringes; disks on all fingers rounded apically and extensively expanded (Fig. 7 ); disk of finger III equal in diameter to the tympanic annulus; disks bearing ventral pads; finger I shorter than II when appressed (Fig. 7 ). Relative lengths of appressed fingers III>IV>II>I. Subarticular tubercles 1-1-2-2.

Hindlimbs slender; foot length (FtL) 12.1 mm, 50.8% of SVL. Toe webbing and toe fringes absent. Relative lengths of appressed toes IV>V>III>II>I. Discs of the toes expanded; width of adjacent phalange 53.7% of disc of toe IV; disc of toe III does not reach penultimate subarticular tubercle of toe IV; toe V beyond that of the level of penultimate subarticular tubercle of toe IV. Femur length (FL) 13.6 mm, tibia length (TL) 14.5 mm, its length is equivalent to 60.9% of SVL. Subarticular tubercles 1-1-2-3-2; supernumerary plantar tubercles numerous, suboval, and low; inner metatarsal tubercle oval; outer metatarsal tubercle rounded, prominent, and smaller than inner metatarsal tubercle. Diameter outer metatarsal tubercle 52.8% of inner metatarsal tubercle; outer tarsal fold absent; inner tarsal fold short. Numerous supernumerary plantar tubercles rounded and barely visible; subarticular tubercles large, round, and conical; toes without lateral fringes; no webbing. Cloacal sheath absent; subcloacal tubercles absent.

Color of holotype in preservative (Fig. 4 ). Dorsum and flanks dark brown; hands in dorsal view, with fingers I and II cream-colored, while fingers III and IV brown with cream-colored bars; dorsal surfaces of the thigh with diffuse dark-brown transversal bars; hidden surfaces of thighs pale brown; venter light brown with a dark-brown suffusion and mottled brown; ventral surfaces of hindlimbs and forelimbs dark brown with a cream-colored suffusion; edge of chin with irregular blotches of dark brown; hands, in ventral view, with palmar tubercle cream-colored and palmar region dark brown.

Color of holotype in life (Fig. 5 ). Dorsal surfaces of body and limbs pink-orange; flanks salmon and sides of the head pink-orange; venter reddish cream-colored on chest and belly, cream-colored on throat; axillary region, groin, and anterior thigh pale orange; ventral surfaces of thighs light brown; iris gray, medially reddish, with black reticulations.

Variation of type series

(Fig. 5 , Table 4 ). In this section, coloration refers to specimens in life and is based on field notes and digital photographs, unless otherwise noted. Dorsal coloration reddish brown with mottled, dark-brown chevrons, usually surrounded by a thin band of lighter color; canthal stripe black; dorsal surfaces of thigh with dark-brown transversal bars; axillary region, groin, and anterior thigh bright orange (e.g., IAvH-Am-10283, IAvH-Am-10276; Fig. 5 ) or uniformly dark brown (e.g., IAvH-Am-10267-68, IAvH-Am-10272; Fig. 5 ). An adult female (IAvH-Am-10277) has a gold paravertebral line (Fig. 5 ). Labial bars dark brown, and postorbital and supratympanic stripe dark (e.g., IAvH-Am-10268, IAvH-Am-10270, IAvH-Am-10272, IAvH-Am-10276-7; Fig. 5 ). In IAvH-Am-10270 and IAvH-Am-10276, flanks with oblique, irregular, dark-brown bars (Fig. 5 ); IAvH-Am-10267 with a W-shaped, light-brown marking on scapula; some specimens with a dark-brown interorbital bar (e.g., IAvH-Am-10268, IAvH-Am-10273-4, IAvH-Am-10279-10280). Pristimantis chamezensis is metachromatic, being lighter in color at night. Teeth positioned posterior to level of choanae and widely separated from each other, which vary between eight to nine. The variation in the skin texture is noteworthy (Fig. 5 ), varying from smooth (e.g., IAvH-Am-10283) to shagreen with scattered tubercles (e.g., IAvH-Am-10267, IAvH-Am-10277). The SVL of adult males ranges from 19.6 to 23.7 mm (Table 4 ), and the SVL of adult females ranges from 19.0 to 24.9 mm (Table 4 ). The HW 35.9-40.3% of SVL in adult males and 41.2-44.1% in adult females. ED 61.6-75.0% of ETS in adult males and 59.1-74.9% in adult females. UEW 58.0-77.6% of interorbital distance (IOD) in adult males and 54.6-78.2% in adult females. TD 39.1-56.0% of ED in adult males and 33-41.8% in adult females. HnL in adult males 29.3% of SVL and 31.2% in adult females. FtL in adult males 45.6-50.4% of SVL and 44.9-51.8% in adult females.

Distribution and natural history.

This species is only known from the type locality at an altitude between 2125-2160 m a.s.l. in an Andean and relictual cloud forest in the Casanare region on the eastern flank of the Cordillera Oriental of Colombia (Fig. 1 ). The locality is within the Cordillera Oriental montane forest ecoregion (sensu Dinerstein et al. 1995) in the Andean region (Middle Orobiome). The forest (Fig. 2 ) is unaffected by human activities and is typified by a canopt of medium-height (up to 20 m). The annual precipitation is between 4600 and 5600 mm with bimodal seasonality. Specimens were found active during the second annual rainy season (August to November) at a temperature of 14 °C resting on mosses and lower leaves of shrubs and ferns in the undergrowth. Pristimantis chamezensis is syntopic with an undescribed species of genus Pristimantis .

Etymology.

The specific epithet is derived from the Municipality of Chámeza, a geopolitical area where the type locality is located. We decided on this name using a citizen science approach, where expert scientists and local people met and discussed a list of possible names and their corresponding meanings. There was consensus on P. chamezensis as the preferred name.

Conservation status.

The direct evaluation of the landscape units (e.g., broad-leaved forest) at the type locality, as well as the map of land cover of Colombia (CORINE Land Cover, IDEAM 2010), allowed us to identify a rapid reduction and low connectivity of its habitat. Based on land cover maps of Chameza’s forest, the potential extent of occurrence is 301,624 km2. Consequently, we propose to categorize P. chamezensis as Vulnerable using the criteria B2a ( IUCN Red List Categories and Criteria 2019).

Figures

Figure 1. Geographic location in Colombia showing the type locality of Pristimantis chamezensis sp. nov. in the western slope of the Cordillera Oriental A red dot shows the type locality B the landscape of natural pristine forest on the eastern slopes of the Central Cordillera Oriental. Map produced using Arc Map, World Imagery.

Figure 2. A general landscape showing the mountains of the Vereda Centro Norte, Chameza forest at Cerro Pan de Azucar (black arrow); type locality of Pristimantis chamezensis sp. nov. B inside the cloud forests; microhabitat where individuals were found. Photographs by Andres Acosta-Galvis.

Figure 4. Pristimantis chamezensis sp. nov. preserved holotype, adult female, IAvH-Am- 10269 (SVL = 23.8 mm) A dorsal view B ventral view C lateral view. White arrow = chin with irregular blotches of dark brown. Scale bar: 10 mm. Photographs by Andres Acosta-Galvis.

Figure 5. Pristimantis chamezensis sp. nov., live specimens. A Holotype, adult female, IAvH-Am- 10269 (SVL = 23.8 mm) B juvenile, IAvH-Am- 10283 (SVL = 17.5 mm) C paratype, adult female, IAvH-Am- 10277 (SVL = 19.7 mm) D paratype, adult male, IAvH-Am- 10267 (SVL = 22.6 mm). Photographs by Andres Acosta-Galvis.

Figure 6. Live specimens (lateral view) of Pristimantis currently known from the eastern Andean Cordillera associated with the Orinoco basin in Colombia. A Pristimantis carranguerorum, Medina Municipality, Cundinamarca Department, IAvH-Am- 14954 (adult female, SVL = 22.6 mm) B Pristimantis medemi, Medina Municipality, Cundinamarca Department, IAvH-Am- 15025 (adult male, SVL = 32.5 mm) C Pristimantis frater, Medina Municipality, Cundinamarca Department, IAvH-Am- 14923 (adult female, SVL = 27.8 mm) D Pristimantis savagei, Medina Municipality, Cundinamarca Department, IAvH-Am- 14933 (adult male, SVL = 23.2 mm) E Pristimantis vilarsi, La Macarena Municipality, Meta Department, IAvH-Am- 15095 (Adult female, SVL = 44.8 mm) F Pristimantis bogotensis, Cabrera Municipality, Cundinamarca Department, IAvH-Am- 15345 (adult male, SVL = 21.9 mm) G Pristimantis anolirex, Santa Barbara Municipality, Santander Department, IAvH-Am- 15654 (juvenile female, SVL = 22.3 mm) H Pristimantis lynchi, Tasco Municipality, Boyaca Department, IAvH-Am- 15871 (adult male, SVL = 22.1 mm) I Pristimantis nicefori, Santa Barbara Municipality, Santander Department, IAvH-Am- 15730 (SVL = 24.5 mm). Photographs by Andres Acosta-Galvis.

Figure 7. Hand and toes of adult male paratype, IAvH-Am- 10271 of Pristimantis chamezensis sp. nov. in ethanol 70 %. A Ventral view of foot B ventral view of hand. Scale bar: 2 mm. Photographs by Andres Acosta-Galvis.