A new Pristimantis (Anura, Strabomantidae) from Yuruaní-tepui, Venezuela Author Rödder, Dennis Author Jungfer, Karl-Heinz text Zootaxa 2008 1814 58 68 journal article 10.5281/zenodo.182875 a2b52ad7-1735-40a3-9877-45925fdee01b 1175-5326 182875 Pristimantis yuruaniensis sp. nov. ( Figs. 1–3 ) Yuruaní Rainfrog Holotype . ZFMK 87278 ( Fig. 1 , 2 ), an adult female, collected on Yuruaní-tepui, Estado Bolívar, Municipio Gran Sabana, Venezuela ( Fig. 3 ), approximately 5° 19´31´´ N , 60° 50´40´´ W , 2300 m a.s.l., by Karin and Helmut Mägdefrau on 18 February 1991 . Paratypes . Two specimens, both collected with the holotype . SMNS 0 9855, adult female; ULABG (Colección de Anfibios y Reptiles, Laboratorio de Biogeografía, Universidad de Los Andes, Mérida, Venezuela ) 7023, adult female. Etymology. The specific epithet derives from the type locality of the new species (Yuruaní-tepui) and the Latin suffix – ensis (meaning native of, or belonging to). Diagnosis. A small-sized Pristimantis sharing the following characters with strabomantid frogs: head about as wide as body; tympanic membrane differentiated or not; cranial crest usually absent; dentigerous process of vomers usually present; terminal discs on digits expanded (with apical papillae in members of the P. calceus Group), bearing well-defined circumferential grooves, supported by T-shaped terminal phalanges; comparative length of fingers I and II variable; subarticular tubercles not protruding; texture of skin on dorsum variable; venter smooth or areolate; range in SVL 13–73 mm ( Hedges et al. 2008 ). In strabomantid frogs, Toe V is commonly as long as or longer than Toe III ( Hedges et al. 2008 ), but slightly shorter in P. yuruaniensis . The species cannot be assigned to any of the species groups of Pristimantis sensu Hedges et al. (2008) (Character status of P. yuruaniensis in parentheses): Species of the bellona, chalceus, frater , galdi, lacrimosus , leptolophus , loustes , orcesi , and unistrigatus species groups have Toe V much longer than Toe III (shorter). Members of the conspicillatus species group have Toe V slightly longer than Toe III (shorter), and commonly basal webbing between toes (absent). Members of the curtipes species group have narrow and rounded digital discs (expanded) and cranial crests (absent). Species of the devillei species group have commonly cranial crests (absent), and Toe V slightly longer than Toe III (shorter). Members of the myersi and orestes species groups have Toe V slightly longer than Toe III (shorter) and narrow and rounded digital discs (expanded). In species of the peruvianus and surdus species group Toe V is slightly longer than Toe III (shorter). FIGURE 1. Female holotype (ZFMK 87278) of Pristimantis yuruaniensis sp. nov. in dorsal (A), ventral (B), and lateral view (C). Scale: 10 mm. Pristimantis yuruaniensis has (1) dorsal skin tubercular in life becoming smooth in preservative, that of venter smooth; (2) tympanum small but distinct, tympanic annulus present, supratympanic fold distinct, consisting of a row of enlarged tubercles, weak middorsal raphe present in preserved specimens, well visible in living specimens; (3) snout rounded to slightly subovoid in dorsal view, acuminate in profile; canthus rostralis slightly concave, edge rounded and indistinct; (4) upper eyelid with one prominent, conical tubercle and irregularly scattered smaller tubercles (tubercles are absent in preserved specimens); (5) choanae elliptical, same size as nostrils; very small and indistinct vomers posterior and medial to choanae, no vomerine dentigerous processes; tongue round, filling the whole mouth; (6) status of vocal slits and nuptial pads unknown (only females available); (7) Finger I slightly shorter than Finger II; (8) fingers without lateral keels; (9) axillary tubercle absent; (10) ulnar tubercles absent; (11) calcars absent; (12) inner metatarsal tubercle oval, outer metatarsal tubercle half the size of inner, indistinct metatarsal tubercle; (13) toes without lateral keels; no webbing; Toe IV with relatively broad elliptical disc, same size than disc on Toe V; discs on Toes I, II and III about 3/4 the size of disc of Toe IV ( Fig. 4 ); (14) in preservative, dorsal and dorsolateral ground color uniform dark brown; ventral coloration light brown; no markings on forearm, shanks and anterior thigh surfaces; in life, dorsum dark brown to grayish-black laterally paler with diffuse yellowish-orange reticulation in the groin, neither lip bars nor crossbars on forearms and shanks; coloration of iris silver to bluish silver with fine black reticulation and a diffuse darker horizontal bar ( Fig. 3 ); (15) SVL 30.4–31.6 mm in females. Pristimantis yuruaniensis is unique among other Venezuelan tepui and Guiana Shield Pristimantis in the following combination of characters: its rather uniform dorsal coloration, absence of lip, forearm and shank bars, its small tympanum, and its advertisement call. In addition, the new species is easily distinguished from other Guiana Shield species by the following characters (those of P. yuruaniensis in parentheses). Pristimantis aracamuni (Barrio-Amorós and Molina) has distinctly notched finger discs (not notched), and a very short Finger I not reaching disc on Finger II (Fingers I and II nearly equal in length) ( Barrio-Amorós and Molina 2006 ). Pristimantis auricarens (Myers and Donnelly) has no tympanic membrane and annulus (present). Adults of P. a v i u s (Myers and Donnelly) have a brown or grey mottled throat in preservative (light brown, no mottling), dark bars reaching from the eye to the upper lip (absent), tympanum 33–41 % of eye length (29.3 and 32.5 %, smaller), a supratympanic fold originating at the corner of the eye and extending to shoulder (consisting of a row of enlarged tubercles), and tip of Toe V extending to distal edge of ultimate subarticular tubercle of Toe IV (reaching to the proximal edge of subarticular tubercle of Toe IV) ( Myers and Donnelly 1997 ). Pristimantis cantitans (Myers and Donnelly) and P. yaviensis (Myers and Donnelly) have basal webbing on toes (absent); hands and feet of P. cantitans bear weak lateral fringes (absent), lip bars radiating from the eye to the lip vary from distinct to vague, but are visible (absent), and it has axillary tubercles (absent) ( Myers and Donnelly 2001 ). Pristimantis cavernibardus (Myers and Donnelly) has deeply notched finger discs (not notched), a pale gular stripe (absent), and P. pruinatus (Myers and Donnelly) has flat warts on the eyelids (absent); in P. cavernibardus and P. pruinatus , when Toe V is adpressed against Toe IV, its disc reaches just beyond the penultimate subarticular tubercle (reaching to the proximal edge of subarticular tubercle of Toe IV). Pristimantis chiastonotus (Lynch and Hoogmoed) has a dorsolateral fold represented by a row of pustules (absent), a large tympanum (small), and small discs on fingers (broad discs). Pristimantis dendrobatoides Means and Savage has a purplish black dorsum with several large red sports (no red spots), venter and undersurfaces of limbs bright red in life (different), and produces malodorous and distasteful skin secretions when handled (not reported). Pristimantis fenestratus (Steindachner) has scattered enlarged tubercles on a shaggreened dorsum (no enlarged tubercles) and prominent lip bars (absent). Pristimantis guaiquinimensis (Schlüter and Rödder) lacks tubercles in the tympanic region (present). Pristimantis gutturalis (Hoogmoed) has upper eyelids covered by somewhat larger warts than ton the rest of the body (no warts), an enlarged heel tubercle (absent), and a white-spotted black throat with a median cream wide stripe (uniform light brown). Pristimantis inguinalis (Parker) has Toe V much longer than Toe III (shorter). Pristimantis jester Means and Savage lacks an auditory apparatus (present) and has Toe V much longer than Toe III (shorter). In P. marahuaka (Fuentes-Ramos and Barrio-Amorós) the tympanum is indistinct (distinct), and no middorsal raphe in preservative (present). Pristimantis marmoratus (Boulenger) has a sparsely tubercular dorsum (tubercular), basal Toe webbing (absent), two black, curved, longitudinal lines from near the upper eyelid toward the scapular region (absent), few, sometimes indistinct bars radiate from the eye to the upper lip (absent), and crossbarred hind limbs (no crossbars) ( Rivero 1961 ; Lescure and Marty 2000 ). Pristimantis memorans (Myers and Donnelly) has a dark W-shaped dorsal mark, 2-3 dark bars radiating from the eye to the upper lip, with intervening light spots (absent) and low and weak ulnar tubercles (absent) ( Myers and Donnelly 1997 ). In P. ockendeni (Boulenger) Toe V is much longer than Toe III (shorter). Pristimantis pulvinatus (Rivero) has a Wshaped mark dorsally, dark crossbars on arms and shanks (absent) and variably distinct oblique lateral bars (absent) ( Myers & Donnelly 1997 ). Pristimantis saltissimus Means and Savage has Toe V much longer than Toe III (shorter). Pristimantis stegolepis (Schlüter and Rödder) has the first finger longer than the second (shorter). Pristimantis tepuiensis (Schlüter and Rödder) has Toe V much longer than Toe III (shorter). Pristimantis vilarsi (Melin) has a W-shaped mark dorsally, and Finger I longer than Finger II (slightly shorter) ( Barrio-Amorós and Molina 2006 ). Pristimantis yaviensis (Myers and Donnelly) has the tympanum concealed beneath skin or absent (distinct) ( Myers and Donnelly 2001 ). Pristimantis zeuctotylus (Lynch and Hoogmoed) has a large tympanum (small), and Finger I is longer than Finger II (slightly shorter) ( Lynch and Hoogmoed 1977 ). In P. zimmermanae (Heyer and Hardy) Toe V is much longer than Toe III (shorter). Description of the holotype . Snout outline rounded to slightly subovoid in dorsal view, acuminate in profile; head weakly distinct from body in dorsal view, HW 41.1 % SVL; canthus rostralis concave, rounded and indistinct; nostrils slightly protuberant, directed dorsolaterally; choanae elliptical, only slightly larger than nostrils; very small and indistinct vomers posterior and medial to choanae, no vomerine dentigerous processes; tongue slightly cordiform, filling the whole mouth; cranial crests absent; nostrils separated by a distance of 3/5 of IOD; eyes large, their diameter slightly smaller than EN; IOD 84.1 % of UEW; upper eyelids with prominent, conical tubercles and many scattered, smaller tubercles (tubercles are absent in preserved specimen, but visible in Fig. 2 A); tympanum distinct, 32.5 % of the diameter of the eye, separated from the eye by a distance of twice the TD; supratympanic fold consisting of a row of well developed tubercles, extending from the corner of the eye posterior to arm insertion; dorsal skin tuberculate in life becoming smooth in preservative, ventral skin smooth; relative length of adpressed fingers I <II <IV <III, not webbed, discs elliptical; discs of Fingers II, III and IV 1.5 times the tympanum diameter, disc of Finger I smaller; palmar and thenar tubercle not identifiable in our preserved specimens; subarticular tubercles as broad as finger, not protruding; status of supernumerary tubercles not identificable due to poor preservation; relative length of adpressed toes I <II <III <V <IV, unwebbed, discs elliptical; disc of Toe IV equal to disc of Finger IV; inner metatarsal tubercle protuberant, oval, larger than outer tubercle; outer metatarsal tubercle ovoid, but weakly identificable due to preservation, subarticular tubercles round, equal to toe width and slightly protruding; status of supernumerary tubercles not identificable due to poor preservation; calcars absent ( Figs. 2 , 4 ); TiL 49.4 % of SVL. Variation. HW 37.7–41.1 % SVL (mean = 39.2; n = 3); IOD 71.7–84.1 % (mean= 76.6; n= 3) of UEW; tympanum 29.3 and 32.5 % of the diameter of the eye; TiL 47.6–55.3 % of SVL (mean= 50.7; n= 3). Colouration. In preservative, dorsal ground color uniform dark brown; ventral coloration light brown, no crossbars on the forearms and the shanks or anterior thigh surfaces; in life, dorsum dark brown to grayishblack becoming lighter laterally with diffuse yellowish-orange reticulation in the groin; ventral surfaces are dirty cream with many minute brownish spots, which become denser on the throat; neither lip bars nor crossbars on forearms and shanks; coloration of iris silver to bluish silver with fine black reticulation and a diffuse darker horizontal bar ( Figs. 2 , 3 ). Measurements of type specimens ( holotype / paratype SMNS 0 9855 / paratype ULABG 7023; in mm): SVL: 31.6 / 30.4 / 31.5; TiL: 15.6 / 16.8 / 15.0; FeL: 16.7 / 16.6 / 15.7; HeL: 13.6 / 12.7 / 12.7; HW: 13.0 / 11.8 / 11.9; Ind : 2.8 / 2.6 /2.6; UEW: 4.4 / 4.6 / 4.6; IOD: 3.7 / 3.4 / 3.3; EN: 3.6 / 3.8 / 3.6; ED: 4.1 / 3.7 / 3.9; TD: 1.4 / 1.4 / 1.2; FD: 1.8 / - / -; 4TD: 1.8 / - / -; ETS: 5.0 / 4.7 / 5.0; 1FiL: 4.6 / 4.1 / -; 2FiL: 5.2 / 4.5 / -; TaL: 9.7 / 10.4 / 9.9; FL: 14.7 / 13.4 / 13.2. Some morphological features could not be properly measured (indicated by a ‘-’) due to dehydration during preservation. Vocalization. The advertisement call of an uncollected male (taken on Yuruaní-tepui on 18 February 1991 between 18:45 and 19:00 h, temperature not recorded; probably about 15°C) can be characterized as a series of indistinctly pulsed, unmodulated notes. The dominant frequency is between 1.86 and 2.08 kHz (maximum energy at 1.98 ± 0.01 kHz; n = 24). Further harmonics are visible in the spectrogram between 2.14 and 2.26 kHz and between 5.73 and 6.38 kHz ( Fig. 5 ). The note repetition rate is 0.39 notes s -1 and the note length is between 0.093 and 0.139 s (mean = 0.122 ± 0.010 s ; n= 24). Internote intervals range between 0.504 and 1.968 s (mean = 1.417 ± 0.374 s ; n= 22). FIGURE 2. Female holotype of Pristimantis yuruaniensis sp. nov. Note enlarged conical tubercle on upper eye lid (A) and fine middorsal raphe (B). FIGURE 3. Further specimens of Pristimantis yuruaniensis sp. nov. and its type locality. A-C: specimens not collected from Yuruaní-tepui. D: female Pristimantis yuruanienis sp. nov. with egg clutch in terrarium. This frog belongs to the type series, but there are no records as to which of them it is. E: type locality of Pristimantis yuruaniensis sp. nov. on top of Yuruaní-tepui. F: Pristimantis cf. yuruanienis , uncollected specimen photographed on Kukenán-tepui. Photos: H. Mägdefrau. FIGURE 4. Hand (A), foot (B), and head of the preserved holotype of Pristimantis yuruaniensis sp. nov. in dorsal (C) and lateral (D) view. FIGURE 5. Oscillogram and sonagram of the advertisement call of Pristimantis yuruanienis sp. nov. (specimen not collected). A second advertisement call of an uncollected specimen (illustrated on Fig. 3 F) putatively belonging to P. yuruaniensis sp. nov. recorded on Kukenán-tepui can be characterized as a series of indistinctly pulsed, not modulated notes. The dominant frequency is between 1.88 and 2.09 kHz (maximum energy at 2.08 ± 0.05 kHz; N = 8). Further harmonics are visible in the spectrogram between 2.23 and 2.28 kHz. The note repetition rate is 0.35 notes s -1 and the note length is between 0.074 and 0.082 s (mean = 0.082 ± 0.006 s ; n= 9). Internote intervals range between 2.86 and 3.86 s (mean = 3.14 ± 0.31 s ; n= 7). Habitat and Natural History. On the tepui, all specimens were found sitting in dense vegetation mainly composed of Rapateaceae , Bromeliaceae , Xyridaceae , Eriocaulaceae and Orchidaceae ( Mägdefrau and Mägdefrau 1994 ) . Four specimens were taken to Germany alive and kept in a terrarium. During captivity, raised air humidity enhanced call activity. A single clutch consisting of nine whitish eggs was laid onto a plastic dish covered with moss during captivity ( Fig. 3 D). Unfortunately, the clutch was destroyed by a fungus infection. Three of the specimens are included in the type series, one – apparently a male – was unfortunately lost. Distribution. Pristimantis yuruaniensis is only known from Yuruaní-tepui (approximately 5° 19´31´´ N , 60° 50´40´´ W , 2300 m a.s.l.) and Kuenán-tepui (approximately 5° 11´13´´ N , 60° 49´20´´ W , 2550 m a.s.l.), Estado Bolívar, Municipio Gran Sabana, Venezuela ( Fig. 6 ).