Pulchrana fantastica, Arifin & Cahyadi & Smart & Jankowski & Haas, 2018

Arifin, Umilaela, Cahyadi, Ganjar, Smart, Utpal, Jankowski, André & Haas, Alexander, 2018, A new species of the genus Pulchrana Dubois, 1992 (Amphibia: Ranidae) from Sumatra, Indonesia, Raffles Bulletin of Zoology 66, pp. 277-299 : 289-295

Pulchrana fantastica , new species

Splendid Stream Frogs (recommended common English name); Katak Elok (Bahasa Indonesia) ( Fig. 5a, b )

Hylarana cf. siberu (Montane NW Sumatra [ Brown & Siler, 2013]) Hylarana sp. Sumatra ( Chan et al., 2014)

Holotype. MZB.Amph.28891 (adult male, Fig. 6a–d ) from Taman Buru Linge Isaq , Aceh Province, Sumatra, Indonesia (N 04.35868° E 097.24404°, 450 m elevation), coll. U. Arifin and G. Cahyadi, 7 March 2014 at 2054 hours.

Paratypes (6). MZB.Amph.28898 (adult male) and MZB. Amph. 28890 (adult male), same information as the holotype, collected between 2036–2145 hours ; MZB. Amph. 28892–93 , MZB. Amph. 28894 ( Fig. 5a ) and MZB. Amph. 28896 (adult males), at N 04.37958° E 097.29158° 1,000 m elevation, 9 March 2014, coll. U. Arifin and G. Cahyadi.

Referenced specimens (11). Seven specimens were collected from Taman Buru Linge Isaq, Aceh Province by U. Arifin and G. Cahyadi: MZB. Amph. 28889 (male) , MZB. Amph. 28943 (juvenile; Fig. 5b ) , MZB. Amph. 28948 (juvenile), at N 04.35868° E 097.24404°, 450 m elevation, 7 March 2014 ; MZB. Amph. 28945 (juvenile) and MZB. Amph. 28947 (juvenile), at N 04.36018° E 097.24580°, 450 m elevation, 7 March 2014 ; MZB. Amph. 28897 (male), at N 04.338036° E 097.28096°, 600 m elevation, 8 March 2014 ; and MZB. Amph. 28944 (juvenile), at N 04.37958° E 097.29158°, 1,000 m elevation, 9 March 2014 . MZB. Amph. 28895 (male), at a locally protected forest in Mane, Kecamatan Ulu Masen (N 04.89949° E 096.13168°, 700 m elevation), 21 March 2014, coll. U. Arifin and G. Cahyadi. MZB. Amph. 28946 (juvenile), at Marpunge, Taman Nasional Gunung Leuser , Aceh Province (N 03.77146° E 097.63773°, 1,065 m elevation), 23 February 2014, coll. U. Arifin and G. Cahyadi. MZB. Amph. 13015 and MZB. Amph. 13011, both males, at Bandar Baru , Sumatera Utara Province (N 03.26287°, E 098.46793°), 5 December 2006 and 10 January 2007, coll. M. Kamsi.

Diagnosis. The following unique combinations of characters distinguish Pulchrana fantastica , new species, from its congeners: (1) a medium size frog, SVL adult males (n = 12) 40.3–45.2 mm; (2) males with large humeral glands (3.2–4.3 mm) on anteroventral surface of brachium, paired internal subgular vocal sacs, nuptial pads absent; (3) dorsal skin finely granular to granulated, with or without keratinised white asperities at tip of each granule ( Fig. 2 ); (4) webbing formula: I(1 ― 1–11/2)II(1/2 ― 2)III(1 ― 2–21/3)IV(2– 21/3 ― 1)V; (5) dorsolateral stripe, thin (0.7–0.9 mm), orange, continuous, anteriorly confluent and posteriorly interconnected by spots; (6) middorsum black with orange line or combination of spots and line in the center, variable in number and length of the line and spots, black without marking in juveniles; (7) dense spots on flanks and dorsal surface limbs, cream or yellow to orange, shape of spots elongated or circular, variable in size; (8) skin of venter smooth, greyish or brown with small light dots on throat and chest, occasionally extending posteriorly to abdomen; (9) iris background black, dense orange stippling ventrally, orange reticulation dorsally, golden centrally, with orange-golden line encircling pupil; (10) upper and lower lip grey or brown with cream or yellow spots (upper lip: 3–7; lower lip: 2–5).

Description of holotype. Adult male with large humeral gland (HG/BL = 40.6%) on anteroventral surface of brachium, paired internal subgular vocal sacs, nuptial pad absent; body slender; head longer than wide (HL/HW = 129.8%); snout obtusely pointed in dorsal view, slightly protruding in lateral view; nares closer to snout than to eye (NSD/END = 56.8%); canthus rostralis sharp, constricted behind nares; loreal region sloping, deeply concave; vomerine teeth distinct, between choana, left (n=3) and right (n=2), teeth barely separated (distance 1.0 mm); choana circular (diameter = 1.0 mm), interchoanal distance 5.3 mm; tongue lanceolate, widening posteriorly, deeply notched in the center, 17.3% free of its total length; eye diameter> interorbital distance (ED/ IOD = 151.2%); internarial distance subequal interorbital distance (IND/IOD = 95.3%); tympanum diameter 58.5% eye diameter; supratympanic fold conspicuous.

Dorsum granulated ( Fig. 2 ); flanks finely granular; venter smooth; forelimb relatively slender. Forearm length subequal to brachial length (BL/FAL = 103.9%); fingers long and slender, without webbing; Fin1L/Fin2L = 103.8%, Fin1L/ Fin4L = 86.5%, Finger III longest; fingertips slightly expanded into rounded disc, circummarginal groove present; disc width of finger wider than width of terminal phalanx of finger: Fin1DW/Fin1TPW = 142.9%, Fin2DW/Fin2TPW = Fin3DW/Fin3TPW = Fin4DW/Fin4TPW = 128.6%; subarticular tubercles present, round, raised prominently; one subarticular tubercle on Finger I and II, two on Finger III and IV; supernumerary tubercles between the base of each finger and subarticular tubercle present, smaller and less prominent than subarticular tubercles, translucent; outer metacarpal tubercle and palmar tubercle distinct, elongate (OMCL/OMCW = 254.5%, PTL/PTW = 227.3%), in contact, not prominent, subequal in length and width (OMCL/PTL = 112.0%, OMCW/PTW = 100.0%); inner metacarpal tubercle oval, prominent, slightly longer than outer metacarpal tubercle and palmar tubercle (IMCL/OMCL = 107.1%; IMCL/PTL = 120.0%).

Hindlimbs long, tibia longer than femur (TBL/FL = 109.3%); relative length of femur, tibia, and tarsus, to SVL is 50.2%, 54.9%, and 30.4%, respectively; skin texture of dorsal side of tibia and posterior region of the thigh finely granulated; tip of toes expanded, circummarginal groove present, widths of the toe disc larger than widths of terminal phalanx of the respective toes: Toe1DW/Toe1TPW = 118.2%, Toe2DW/ Toe2TPW = 137.5%, Toe3DW/Toe3TPW = Toe4DW/ Toe4TPW = 128.6%, Toe5DW/Toe5TPW = 133.3%; subarticular tubercles distinct, round, highly elevated, translucent; number of subarticular tubercle for each toe: I(1), II(1), III(2), IV(3), V(2); relative toe length: I<II<V≤III<IV, Toe3L/Toe5L = 104.4%; outer metatarsal tubercle raised, oval (OMTL/OMTW = 112.5%), translucent; inner metatarsal tubercle distinct and long (IMTL/IMTW = 200.0%), elevated, translucent, larger than outer metatarsal tubercles (IMTL/ OMTL = 200.0%); webbing formula: I(1 - ― 10)II(1/2 ― 2 -) III(1 - ― 2 +)IV(2 - ― 1 -)V.

Colouration. In life, dorsal skin black; middorsum with orange spot behind the eyes continued by orange line (divided into two, equal length) up to approximately level of sacral vertebra, two yellow spots, and one orange spot in the pelvic region (in the middle of two ilium, in line with joint between ilium and femur); continuous straight, orange stripes (width = 0.7 mm), from tip of snout, along canthus rostralis, following lateral margin of palpebra, continuing dorsolaterally to sacrum, breaking up into five orangeround spots at the posterior pelvic region that connect the dorsolateral stripes from both sides into a loop; flanks brown, lighter ventrally; yellow spots from behind tympanum to groin; round cream spot present between tympanum and eye; two cream spots at end of rictus; venter greyish-brown; whitish dots on throat, chest, and abdomen; iris background black, dense orange reticulation ventrally, orange reticulation dorsally, with golden centrally, solid orange line encircling pupil; upper lip brownish-grey with white spots (n = 6 on left, 5 on right); lower labial region grey, with three small white spots on each side of lower lip; dorsal surface of limbs brown, with dense round spots and elongate, yellow to orange markings, variable in size; small whitish spots on rear of thigh; interdigital webbing brown. In preservative, dorsal skin dark brown; flanks and dorsal surface of limbs brown, lighter than dorsum; ventral skin creamy brown, with whitish spots; dorsolateral stripe and spots on dorsum, flanks, and dorsal surface of limbs faded to cream or whitish; iris grey.

Variation. We observed variation within 18 specimens of Pulchrana fantastica , new species; comparison of morphological traits among the seven type specimens of P. fantastica , new species, is provided in Table 6. Dorsum texture of adults finely granulated (flat surface with distinct granules; Fig. 2a ) or granular (granule distinct, more raised, with white tipped asperities present or absent; Fig. 2b, c ). Juvenile specimens lack middorsal marking, adults middorsum with markings (yellow line and or spots from central postocular region, extending posteriorly to vent, variable in length), except for MZB.Amph.28896 without marking; in life, juvenile colouration of spots on dorsal surfaces of limbs whitish or pale yellow (except for MZB. Amph.28943 and MZB.Amph.28946 possess few orange spots); venter grey to brown, with light dots, variably from throat to abdomen; orange dorsolateral stripe in juveniles and adults, straight, in most cases continuous from rostrum to beyond sacrum, occasionally with one or two interruptions of the stripe ( Table 6); pattern of spots on dorsal surfaces of limbs in adults vary in colour and shape: usually yellow to orange, round or elongated, from two or more connected spots; posterior surfaces of thighs brown (similar to dorsum), with yellowish spots, smaller than those on the dorsum; number of vomerine teeth 2–3 on each side; number of spots on upper lip (left, right): 3–6, 3–7; number of spots on lower lip 2–5 on each side; webbing formula I(1 ― 1–11/2) II(1/2–1 ― 2)III(1 ― 2–21/3)IV(2–21/3 ― 1)V.

Range. Pulchrana fantastica , new species, is currently known from Aceh Province (Marpunge, Taman Nasional Gunung Leuser; Taman Buru Linge Isaq; Mane) and Sumatera Utara Province (Bandar Baru, Langkat) at an elevation between 450–1,065 m ( Fig. 4 ).

Natural history. The new species is currently known only from primary forest. All Aceh specimens were collected from within protected areas (Taman Nasional Gunung Leuser, Taman Buru Linge Isaq, and local protected forest in Mane). The holotype was first observed calling from among leaf litter, under low vegetation, about 2.5 m from a small stream (2–3 m width). Two of the paratypes (MZB.Amph.28890 and MZB.Amph.28898) and three juveniles (referenced specimens: MZB.Amph.28889, MZB.Amph.28943, MZB. Amph.28948) were collected the same night at the type locality. MZB.Amph.28889 was perched on a fern growing over above dead log, approximately 1.0 m from a nearby stream at 2038 hours. MZB.Amph.28890 was perched on a dead branch in a stream, approximately 5 cm above the surface of the water at 2145 hours. MZB.Amph.28898 was encountered at 2048 hours on a dead log (d = 30 cm), approximately 1.2 m from the stream. MZB.Amph.28943 was caught seated on an orchid leaf, on the forest floor at 2036 hours. MZB.Amph.28948 was collected at 2036 hours from an orchid leaf, approximately 10 cm above the ground. At the time, the nearby stream was narrower than its usual width, due to low seasonal precipitation. Other species recorded in the same vicinity included one species of ranid frog ( Huia sumatrana ), two species of colubrid snakes ( Boiga nigriceps and B. jaspidea ), one species of scincid lizard ( Eutropis sp. ), and orangutans ( Pongo abelii ). The forest type was a typical lowland dipterocap forest. The four remaining paratypes (MZB.Amph.28892, MZB. Amph.28894, MZB.Amph.28896, and MZB.Amph.28944) were collected in the same region, but at higher elevation (1,000 m). The stream at this elevation was surrounded by primary forest, and was approximately 5–6 m wide. Large rocks were prevalent and the stream water was silty and red in colour. The resting perches of collected animals included rocks, dead logs, and roots. Pictures of habitat for this species are provided ( Fig. 3b, c ).

Etymology. The specific epithet is nominative feminine derivative of the Greek phantastikós. We apply this adjective with a contemporary spelling and an implied meaning of “being beyond imagination” with reference to the extraordinary beauty of this species.

Comparisons. Pulchrana banjarana , P. centropeninsularis , P. fantastica , new species, P. guttmani , P. grandocula , P. mangyanum , P. moellendorffi , P. picturata , P. siberu , P. signata , and P. similis can be distinguished from P. baramica , P. glandulosa , P. laterimaculata , P. melanomenta , P. rawa , and P. debussyi by having light spots (yellowish white, grey, orange or red in life) on dark (often black) dorsum; dorsolateral stripes present or absent, when present then in the form of a continuous or broken stripe from snout to sacral region or beyond.

Pulchrana centropeninsularis , P. fantastica , new species, and P. siberu differ from P. banjarana , P. guttmani , P. grandocula , P. mangyanum , P. moellendorffi , P. picturata , P. signata , and P. similis by the absence (vs. presence) of nuptial pads in males; the presence of distinct pale spots on the limbs (vs. broad bars or indistinct blotches in all other species); the presence of orange to red dorsolateral stripes (vs. white, yellow, pale orange or tan in other species), by reduction in webbing of toes: one phalanx free for Toe III and Toe V, and two to two and half phalanges free for Toe IV (vs. web nearly complete) ( Brown & Guttman, 2002).

Pulchrana fantastica , new species, (n = 12) can be distinguished from P. centropeninsularis (Jambi specimens, n males = 3) by larger body size (mean SVL 42.4 mm vs. 38.7 mm); larger humeral gland (mean HG length 3.9 mm vs. 3.4 mm); number of spots on upper lip 3–7 (vs. 2–4) on each side; number of spots on lower lip 2–5 (vs. 1–3) on each side; mean ratio of tongue length of notched region and total tongue length 18.5% (vs. 22.2%); dorsal skin texture finely granulated to granular (vs. granular); with or without (vs. without) white tipped asperity at center of each granule; dorsolateral stripe thin, mean of width 0.8 mm (vs. 1.2 mm); middorsum black, marked with short or longer line with breaks in adults and unmarked dorsum in juveniles (vs. black, unmarked); ventral skin grey to brown, with white spots on throat, chest, and sometimes to abdomen (vs. grey to brown, with light spots on throat and light reticulation on venter); mean of tibia length 23.2 mm (vs. 20.6 mm); yellow to orange (vs. yellow spots), round or elongate (vs. usually round), dense spots on dorsal side of limbs; webbing formula: I(1 ― 1–11/2)II(1/2 ― 2)III(1 ― 2–21/3)IV(2–21/3 ― 1) V [vs. I(1/2–1 ― 1–2)II(1/2–1 ― 11/2–21/2)III(1 ― 2–3) IV(11/2–3 ― 1/2–1)V]. Morphological comparison showing dorsal, ventral, palmar and plantar views of these two species are provided in Fig. 6 .

Pulchrana fantastica , new species, differs in morphology from P. siberu ( Dring et al., 1990; Brown & Guttman, 2002) by larger body size (mean SVL 42.4 mm vs. 37.0 mm); shorter humeral gland (mean HG length 3.9 mm vs. 4.5 mm); dorsal skin texture finely granulated to granular (vs. granular); with or without white tipped asperity at center of each granule; dorsolateral stripe thin, mean of width 0.8 mm (vs. 1.1 mm in P. siberu ); middorsal colour pattern black, marked with short or longer line with break in adults and unmarked in juveniles (vs. black, unmarked); yellow to orange (vs. usually orange), round or long (vs. round), dense (vs. sparse) spots on dorsal side of limbs; throat grey to brown with light spots in life (vs. light grey); abdomen grey to brown with light reticulation in life (vs. light grey); ventral skin of throat, chest, abdomen, limbs grey to brown, with white spots on throat, chest, and sometimes to abdomen (vs. light grey, usually without spots or reticulation); mean of tibia length 23.2 mm (vs. 20.9 mm). Morphological comparison showing dorsal, ventral, palmar and plantar view of these two species is provided in Fig. 6 .

Figures

Fig. 5. Plates comparing the three closely allied Sumatran Pulchrana species (a) P. fantastica, new species, MZB.Amph.28894, adult male, paratype, Aceh; (b) P. fantastica, new species, MZB.Amph.28943, juvenile, Aceh; (c) P. centropeninsularis, adult male, Jambi; (d) P. siberu, female, Pagai Selatan. Photo by U. Arifin (a, b, d); A. Jankowski (c).

Fig. 6. Dorsal (a), ventral (b), palmar (c), and plantar (d) views of Pulchrana fantastica, new species (MZB.Amph.28891, male, holotype, Aceh); (e–h) P. centropeninsularis (MZB.Amph.28767, male, Jambi); (i–l) P. siberu (BMNH 1979.306, male, holotype, Siberut). Scale bar = 10 mm. Photo by G. Cahyadi (a–h); U. Arifin (i–l).

Fig. 2. Left to right; examples of dorsal skin textures in members of the Pulchrana siberu, P. centropeninsularis, and P. fantastica, new species: (a) finely granulated (MZB.Amph.28896); (b) granular (MZB.Amph.28765); (c) or with white tipped keratinised asperities (MZB. Amph.13011). Scale bar = 3 mm. Photo by G. Cahyadi.

Fig. 4. Geographical distribution of Pulchrana centropeninsularis (white circles), P. fantastica, new species (black triangles), and P. siberu (red stars). Locality information: Mane (1); Taman Buru Linge Isaq (2); Taman Nasional Gunung Leuser (3); Bandar Baru (4), Lakum Forest Reserve & Kuala Gandah, Pahang (5); Bukit Tigapuluh (6); Hutan Harapan (7); Siberut (8); Sipora (9); and Pagai Selatan (10). Type locality for each species indicated by arrow. Map was prepared using GeoMapApp (Ryan et al., 2009).

Fig. 3. Habitat of Pulchrana centropeninsularis, Hutan Harapan, Jambi (a) and P. fantastica, new species, Taman Buru Linge Isaq, Aceh (b, c). Photo by A. Jankowski (a); G. Cahyadi (b, c).