Species Description: Davis JR. Grismer LL, Klabacka RL, Muin MA, Quah ESH, Anuar S, Wood Jr PL, Sites JW 2016 The phylogenetic relationships of a new Stream Toad of the genus Ansonia Stoliczka, 1870 (Anura: Bufonidae) from a montane region in Peninsular Malaysia. Zootaxa 4103: 137-153.
Ansonia smeagol lacks paratoid glands, but the upper eyelid, interorbital region, canthus, and dorsum of the snout has raised tubercles with keratinized tips. Some tubercles are dispersed on the lores and a single row of small spinules can be found on the upper lip and outer margin of the eyelid. There is a large tubercles located above the rictus and posterior to the tympanum. There are also small spinules around the rictus. Large, interspersed tubercles with keratinized spinules are scattered over the back, flanks, and dorsal part of limbs. The ventral surface, omitting the hands and feet, has minute, evenly-spaced spinules that is more dense in the pectoral area. The ventrum is otherwise finely granular (Davis et al. 2016).
Like in other Ansonia species, the limbs and digits are long and slender. The hands have basal webbing that does not extend to the proximal subarticular tubercles. The inner and outer metacarpal tubercles are distinct and oval, with the inner slightly smaller. The relative finger length is I < II < IV < III. The fingertips are slightly expanded and rounded, but do not form discs. The subarticular tubercles are distinct (Davis et al. 2016).
The foot is longer than the tibia. The inner metatarsal tubercle is elongate and slightly larger than the raised, oval outer metatarsal tubercle. The foot is webbed, the subarticular tubercles are distinct, and the toe tips are rounded, but do not have discs. The relative toe lengths are I < II < III < V < IV. The webbing formula is I 1, II ½ - 2, III 1 ½ - 2, IV 3 ½ -3.7, V 1.5 (Davis et al. 2016).
Ansonia smeagol is closely related to A. jeetsukumarani, A. lumut, A. malayana, and A. penangensis. Ansonia jeetsukumarani has a dorsolateral row of tubercles and orange coloration on the flanks and limbs, but lacks an inner metatarsal tubercle that differentiates it from A. smeagol. Compared to A. lumut, A. smeagol is slightly smaller (24.6 - 27.4 mm vs 27.7 - 31.6 mm), lacks a dorsolateral row of enlarged tubercles and a large yellow tubercle at the angle of the jaw, and has a coarser abdomen. Ansonia malayana has a large yellow tubercle at the angle of the jaw, orange coloration on the limbs, and an X pattern and orange coloration on the dorsum. Ansonia penangenis is larger (37.2 mm) and has a tarsal ridge and orange coloration on the limbs (Davis et al. 2016).
In life, the dorsum of A. smeagol is dark brown to black, with white patches randomly distributed on the flanks. White patches can also be found in the following locations: Four on upper right lip, three on upper left lip, several on ventral side of mandible, near the vent, and anterior portion of the thigh. The underside of the thigh is much lighter than the rest of the body. Finally, they have a large white tubercle at rictus and a smaller one between that and posterior upper labial on left side of head only (Davis et al. 2016).
One paratype was lighter on the ventral portion of the thigh compared to the rest of the body, and had more white spotting. Only the holotype had a white tubercle at the rictus (Davis et al. 2016).
Distribution and Habitat
Life History, Abundance, Activity, and Special Behaviors
Three of the five specimens collected during the month of March were gravid, indicating that March is within the breeding season (Davis et al. 2016).
Possible reasons for amphibian decline
General habitat alteration and loss
Despite consistent typologies, phylogenies of the genus Ansonia all suffer from poorly supported nodes. However, Bayesian Inference and Maximum Likelihood analysis of 2451 base pairs of a combination of the mitochondrial genes 12S, tRNAval, and 16S indicate that A. smeagol is sister to the clade formed by A. lumut, A. penangensis, A. malayana and A. jeetsukumarani (Davis et al. 2016).
It was previously thought that the specimens later used to describe A. smeagol were members of A. jeetsukumarania, however the two species are not the most closely related. Instead, it is strongly supported that A. jeetsukumarania and A. malayana are sister species (Davis et al. 2016).
The species epithet “smeagol” is a reference to Sméagol, a character in J.R.R. Tolkien’s “The Hobbit”, who shares many of the same characteristics including long thin limbs and bulbous eyes (Davis et al. 2016).
The species in the clade sister to A. smegol, which includes A. lumut, A. penangensis, A. malayana and A. jeetsukumarani, all have fragmented and circumscribed distributions as a result of their lotic lifestyle and dependence on consistent water flow (Davis et al. 2016).
Davis, H., Grismer, L., Klabacka, R., Muin, M., Quah, E., Anuar, S., Wood Jr., P., Sites Jr., J. (2016). ''The phylogenetic relationships of a new Stream Toad of the genus Ansonia Stoliczka, 1870 (Anura: Bufonidae) from a montane region in Peninsular Malaysia.'' Zootaxa, 4103(2), 137-153.
Written by: Dennis Lee (2018-06-22)
Edited by: Ann T. Chang (2018-06-25)
Species Account Citation: AmphibiaWeb 2018 Ansonia smeagol: Precious Stream-toad <https://amphibiaweb.org/species/8466> University of California, Berkeley, CA, USA. Accessed Apr 14, 2021.
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Citation: AmphibiaWeb. 2021. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 14 Apr 2021.
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