Ansonia teneritas, Lea E. Waser, Manuel Schweizer, Alexander Haas, Indraneil Das, André Jankowski, Pui Yong Min & Stefan T. Hertwig, 2017
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publication ID |
https://doi.org/ 10.1007/s13127-016-0294-2 |
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DOI |
https://doi.org/10.5281/zenodo.6057444 |
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persistent identifier |
https://treatment.plazi.org/id/DE59D352-FFC1-FFA1-FF6B-FCDAFC462671 |
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treatment provided by |
Plazi |
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scientific name |
Ansonia teneritas |
| status |
sp. nov. |
Ansonia teneritas View in CoL , sp. nov.
Holotype: NMBE 1057364 , from a small stream on the upper reaches of the Sungei Julan on the northern side of the Usun Apau Plateau just above the falls of the Sungei Julan Valley, Usun Apau National Park , Sarawak, East Malaysia (Borneo). GPS N 03.03292°, E 114.66647°, 1002 m a.s.l, coll. A. Haas, Pui Yong Min, S.T. Hertwig & A. Jankowski, 28. August 2010. Adult male. GoogleMaps
Paratypes: NMBE 1057318 – 1057327 , ZRC 1.12525 - 12526 , from the same locality as holotype, coll. A. Haas, Pui Yong Min, S.T. Hertwig & A. Jankowski, 27 and 28 August 2010; ZMH A11568 , from Gunung Hose , Sarawak, East Malaysia (Borneo), GPS N 02.23526°, E 113.68693°, 1104 m asl., coll. A. Haas & Y.M. Pui, 25. August 2011. GoogleMaps
Diagnosis
The new species is assigned to the genus Ansonia on the basis of a robustly supported phylogenetic hypothesis ( Fig. 3 View Fig. 3 ) and the presence of the following morphological characters: body slender, subarticular tubercles indistinct, limbs long and slen- der, webbing membranous, parotid glands absent, and tympanum visible ( Inger 1960, 1966).
Ansonia teneritas sp. nov. can be distinguished from all congeners by the following combination of characters: (1) SVL in males <22 mm, in females <25 mm; (2) snout clearly projecting in profile; (3) head depressed; (4) longitudinal interorbital ridges absent; (5) first finger short, not reaching base of tip of second finger when adpressed; (6) no sharp tarsal ridge; (7) skin flaps on posterior thigh near vent absent; (8) warts on temporal regions not enlarged; (9) coloration olive-green with a contrasting dark brown pattern on head and dorsum; (10) whitish pattern below the eye on upper lip; (11) white warts behind jaw joint, on shoulders and flanks; (12) iris bright redorange with an irregular network of black reticulations.
Description of holotype
Habitus very slender ( Fig. 5 View Fig. 5 ); body slightly wider than head; head depressed ( Fig. 6 View Fig. 6 ); head shorter than it is wide; rostrum truncate in dorsal view; tip of snout rounded, longer than canthus, protruding in lateral view, clearly projecting beyond tip of mandible; rostral length shorter than eye diameter; nostril lateral, closer to snout tip than to eye; indistinct vertical ridge between tip of snout and centre of maxilla; canthus rounded; lores vertical and slightly concave; eye diameter greater than eye-nostril distance; interorbital distance slightly larger than the upper eyelid; tympanum round and distinct; eye diameter 3.48 times greater than tympanic diameter; distance from eye to tympanum 0.43 mm
Fingers slender; tips slightly expanded forming small, spatulate discs; first finger significantly shorter than second; nuptial pads with blackish brown spines on first finger; subarticular tubercles weak and indistinct, exclusively below the proximal articulation of the first phalange, absent below distal phalanges; palm smooth with large, distinct rounded palmar tubercles; tips of all toes rounded; fifth toe slightly longer than third; membranous web reaching disc of first toe, disc on both sides of second toe, third toe with one and two-thirds phalanges free, fourth with three phalanges free, fifth toe with two phalanges free of web. Subarticular tubercles indistinct; two metatarsal tubercles, both oval and slightly raised; tarsal fold absent.
Skin of head, dorsum, flanks, and dorsal surfaces of limbs with scattered, isolated, flat, rounded warts of heterogeneous size, warts on temporal and dorsolateral regions not significantly larger ( Figs. 5 View Fig. 5 and 7 View Fig. 7 ); warts on head, dorsum, flanks, and limbs often terminating in fine brown keratinous spines or caps; spines below the symphysis of mandibles absent, but one row of very small, spineless tubercles along the ventral face of the lower jaw; skin flaps on posterior thigh near vent absent.
Colour in preservative grayish brown with a contrasting dark gray pattern of bands and spots on head and dorsum beginning at the eyes and running to the forehead and shoulders, forming an x with a light spot in its center; irregular light spot below the eye on upper lip; limbs gray brown with contrasting lighter cross bands; venter pale yellowish white with dark mottling on throat, chest, and belly; small, whitish tubercles present on the pectoral region and the venter ( Fig. 7 View Fig. 7 ).
Coloration in life olive-green with a contrasting dark brown pattern of irregular spots and bands, often forming an x-shape between the eyes, on forehead, and on shoulders; larger warts on dorsum yellow to orange, whitish warts ventrolaterally on flanks and from jaw joint to shoulder, an irregular whitish spot below the eye on the upper lip, limbs dark brown with yellow crossbars ( Fig. 5 View Fig. 5 ); venter pale yellowish white with brown mottling, especially on throat and chest, and interspersed with whitish tubercles. Iris bright red-orange with an irregular network of black reticulations ( Fig. 5 View Fig. 5 ).
Variation
The extent of the dark pattern on throat, chest, and venter varies from a few markings on the anterior part of the throat to intense mottling on throat, chest, and belly ( Fig. 7 View Fig. 7 ). Some specimens possess up to three rows of very small, spineless tubercles along the ventral face of the lower jaws, while in other specimens, such tubercles are lacking. There is no noticeable variation in the described characters between the specimens from Usun Apau National Park and the single female specimen from Gunung Hose, Sarawak.
Sexual dimorphism
Males are smaller (SVL 1 9.1 6 – 2 1.5 3 mm) than females (21.37 – 24.4 mm); males possess vocal sacs and nuptial pads with numerous blackish brown spines. Females have less extensive webbing: the first toe is fully webbed, the second toe is about one phalange free of web, the third toe about two, the fourth about three to three and a half, and the fifth about two to two and a half free of web.
Comparison
The following characters distinguish Ansonia teneritas sp. nov. from its other Bornean congeners: Ansonia albomaculata Inger 1960 : tympanum obscured by skin; head not depressed; sharp tarsal ridge present; skin of body and limbs uniformly covered with small, round warts; an oblique light band from the posterior corner of the eye to axilla; no contrasting pattern on head, dorsum, or limbs ( Inger 1966; Inger and Stuebing 2005). Ansonia echinata : black spines under mandible, large ventrolateral tubercles tipped with small black spines; spinose tubercles on top of snout with black spines, no contrasting pattern on head, dorsum, or limbs (Inger and Stuebing 200 9). Ansonia fuliginea : larger body size (males 32 – 36 mm, females 38 – 44 mm); snout vertical in profile; head not depressed; no contrasting pattern on head, dorsum, or limbs, blackish on sides and underside ( Inger 1960, 1966; Inger and Stuebing 2005). Ansonia guibei Inger 1966 : snout vertical in profile; head not depressed; first finger long, reaching base of second when adpressed; fourth and second finger equal in length; membranous web reaching tips of third and fifth toes; skin dorsally and dorsolaterally with numerous round warts with clusters of dark spinules; oblique flap of skin present on each side of the vent; no contrasting pattern on head, dorsum, or limbs (Inger 196 6; Inger and Stuebing 20 0 5). Ansonia hanitschi : larger body size (males 20 – 28 mm, females 28 – 35 mm); males with a few spinose tubercles below symphysis of the mandibles; colour pattern on head, dorsum, and limbs obscure and less contrasting ( Dring 1983; Inger 1966; Inger and Stuebing 2005); Ansonia latidisca : larger body size (males 35 mm, females 5 5 mm); head not depressed; snout almost vertical in profile; tips of the three outer fingers dilated into truncate discs, that of third as wide as tympanum; forelimb very long and slender; two rows of interorbital, conical tubercles; different colour pattern on head and back consisting of a bright green background with a distinct pattern of blackish brown spots and scattered orange or red warts ( Inger 1966; Matsui et al. 2012 Ansonia leptopus : larger body size (males 35 mm, females 55 mm); head not depressed; first finger long, reaching disc of second; dorsolateral warts larger, males with rows of brown spines under mandible; no contrasting pattern on head, dorsum, or limbs ( Inger 1966; Inger and Dring 1988; Inger and Stuebing 2005). Ansonia longidigita : larger body size (males 50 mm, females 65 mm); head not depressed; first finger long, reaching tip of disc of second; snout almost vertical in profile; a pair of longitudinal rows of tubercles in interorbital space; males with three to six rows of brown or black spines under mandible; no contrasting pattern on head or dorsum (Inger 1 966; Inger and Dring 1988; Inger and Stuebing 2005; Matsui et al. 2010). Ansonia minuta : head not depressed; distinct tarsal ridge; nuptial pads absent; third and fifth toes webbed to disc in males; more warts on dorsal face of the head; warts on dorsum and flanks not spinose, dark pattern on dorsum less contrasting (Inger 19 60, 1966; Inger and Stuebing 2005). Ansonia platysoma : warts on dorsum and flanks often without or with indistinct keratinous spines or caps; nuptial pads consisting of spines with a paler brown coloration; third toe usually webbed to disc in males; no white pattern on upper lip; no white warts on shoulders or flanks; colour pattern on head, dorsum, and limbs obscure and less contrasting ( Inger 1960, 1966). Ansonia spinulifer : larger body size (males 30 – 4 0, females 40 – 45); head not depressed; first finger reaching tip of second when adpressed; dorsal and dorsolateral warts large, elevated and juxtaposed, tipped with one or three strong melanistic spines; males with spinose tubercles un- der mandibular symphysis and lower jaw; adults black on top with a light spot between the shoulders but without a contrasting pattern on head, dorsum, or limbs ( Inger and Dring 1988; Inger and Stuebing 2 0 0 5). Ansonia torrentis Dring 1983 : larger body size (males 30 – 33 mm); head relatively wide in comparison to body; warts on dorsum without keratinous spines; males with spinose tubercles under mandibular symphysis and lower jaw ( Dring 1983). Ansonia vidua : larger body size (females 30 – 34 mm); head not depressed; two low, curved longitudinal ridges present on the interorbital region; skin of back, flanks and upper surfaces of the limbs covered with numerous small, regular, flat, rounded warts resulting in a velvet-like appearance; coloration of head, body and limbs uniformly black-brown with no markings ( Hertwig et al. 2014).
Etymology
The species name teneritas, Latin for ‘ tenderness ’, refers to the gracile body shape and small body size of this species in comparison to congeners. We suggest the English name ‘ Gracile Slender Toad ’.
Ecological notes
The type locality of Ansonia teneritas sp. nov. is a small tributary of the upper reaches of the Sungei Julan, just above the spectacular falls of the Sungei Julan Valley on the northern side of the Usun Apau plateau ( Fig. 8 View Fig. 8 ). The Usun Apau plateau is part of the Central Bornean plateau and forms the watershed between the Rejang and Baram river basins in central Sarawak (Hutchison 2005; Rousseau 1977). The Sungei Julan is a tributary of the Baram drainage system. It consist of several tablelands and smaller plateaus with an elevation of approximately 760 – 1 0 0 0 m with sharply cut edges, precipitous cliffs, and deep marginal embayments (Hutchison 2005). The Usun Apau highlands were formed by extensive volcanic activity during the Upper Miocene to Quaternary, and the few mountains that stand over 300 m above the tablelands are relicts of former volcanoes (Hutchison 2005). As a result of their volcanic formation history the high tablelands of the central area are built up of dacite tuff and agglomerate, while the southern mountains are covered by basalt lava (Hutchison 200 5; Campbell 1956). The area covers about 700 sq. km of forest and has been protected as the Usun Apau National Park since 200 5.
The small stream at the type locality is presumably permanent and has a moderate gradient. The stream bed consists of alternating small shallow rocky pools (20 to 50 cm depth) and fast-running sections on bedrock (0.5 to 1.5 m in width, depending on the amount of precipitation) ( Fig. 8 View Fig. 8 ). Below the type locality the stream flows to the Sungei Julan just below the upper tier of the Eastern Julan falls in the steep Sungei Julan Valley. The vegetation at the type locality is primary lower montane forest. On the surrounding hills the forest type changes to kerangas (Bornean heath) forest. All specimens of Ansonia teneritas sp. nov. were collected at night from rocks or low vegetation along the stream. Males call at night from saplings on the stream banks or on bedrock.
Adult frogs of the following species were detected in the immediate vicinity of the stream and the surrounding forest: Ansonia longidigita Inger , 1 9 6 0; Hylarana picturata (Boulenger 1 9 2 0); Leptobrachella mjobergi Smith , 1 9 2 5; Limnonectes cf. kuhlii (Tschudi, 1838) ; Limnonectes ibanorum (Inger 1 9 6 4); Meristogenys sp., Metaphrynella sundana (Peters, 18 67); Microhyla petrigena Inger and Frogner 1979 ; Occidozyga laevis ( Günther 1858) ; Philautus hosii ( Boulenger 1895) ; Philautus macroscelis ( Boulenger 1896) ; Philautus cf. mjobergi Smith , 1 9 2 5; Philautus tectus Dring , 1 9 8 7; and Staurois parvus Inger and Haile, 1959 .
The second locality from where Ansonia teneritas is known is the Gunung Hose, a relatively isolated, remote, and poorly explored mountain range in central Sarawak. The Gunung Hose range is composed of volcanic rock forming frequently steep cliff faces ( Lee, 2002). The single specimen was found on low vegetation by a deeply entrenched small stream in a selectively logged secondary forest near a logging road. At the same locality adults of Ansonia longidigita Inger, 1960 and Staurois guttatus ( Günther, 1858) were found; additionally, Rhacophorus borneensis Matsui, Shimada , and Sudin, 2013 was heard calling.
The larval stages and call of the new Ansonia remain undocumented.
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