Megophrys selatanensis, Munir & Nishikawa & Hamidy & Smith, 2021

Munir, Misbahul, Nishikawa, Kanto, Hamidy, Amir & Smith, Eric N., 2021, Two new species of Megophrys Kuhl and Van Hasselt (Amphibia: Megophryidae) from Sumatra, Indonesia, Zootaxa 5057 (4), pp. 503-529 : 507-514

publication ID	https://doi.org/ 10.11646/zootaxa.5057.4.3
publication LSID	lsid:zoobank.org:pub:A3C378BB-58ED-4A18-8F52-1D00E58E6F1E
DOI	https://doi.org/10.5281/zenodo.5601715
persistent identifier	https://treatment.plazi.org/id/C83EE36B-C447-FD72-FF19-29C761FBFA65
treatment provided by	Plazi
scientific name	Megophrys selatanensis
status	sp. nov.

Treatment

Megophrys selatanensis sp. nov.

( Figs. 2 View FIGURE 2 A−F, 3A−E)

Holotype MZB. Amph 22411 (field number ENS 14208; GenBank accession no. MT 710704 View Materials ; Figs. 2A–B View FIGURE 2 , 3A–E View FIGURE 3 ; Megophrys sp. south in Fig. 1 View FIGURE 1 and Table 1 View TABLE 1 ), an adult female collected from the eastern side of Bukit Barisan Mountain range in southern Sumatra, Lampung Province, Tanggamus Regency , Ulubelu District , Ngarip (5.280170°S, 104.557240°E, 1439 m a.s.l., Fig. 6 View FIGURE 6 ), by Elijah Wostl, Kyle A. O’Connell and Ahmad Muammar Kadafi at 2040 h on 10 June 2013. GoogleMaps

Paratype UTA A-66176 (formerly MZB. Amph 25988, field number ENS 17384; GenBank accession no. MT 710705 View Materials ; Fig. 2 View FIGURE 2 C−D), subadult male collected at 1959 h on 8 July 2015 from the eastern side of Bukit Barisan Mountain range in southern Sumatra, Sumatra Selatan Province, Muara Enim Regency, Semendo Darat Ulu District , Segamit , near Gunung Patah (4.219890°S, 103.471250°E, 1624 m a.s.l., Fig. 6 View FIGURE 6 ) by Elijah Wostl, Eric N. Smith, and Farid Akhsani GoogleMaps .

Referred specimens MZB. Amph 32593 (field number ENS 14202; GenBank accession no. MT 710706 View Materials ; Fig. 2F View FIGURE 2 ) a juvenile male (SVLh 16.08 mm), same locality and collector as holotype ; UTA A-66177 (field number ENS 17403; GenBank accession no. MT 710707 View Materials ; Fig. 2E View FIGURE 2 ) a juvenile male (SVLh 23.5 mm), same locality and collectors as paratype .

Etymology. The specific name selatanensis is derived from the Indonesian word Selatan (=south), as the new species exhibits a southern distribution within Sumatra and the Latin suffix – ensis meaning from that place.

Suggested English common name. South-Sumatran Horned-Frog

Suggested Indonesian name. Katak-tanduk Sumatra-selatan.

Diagnosis. The new species was assigned to the genus Megophrys based on the combination of the following morphological characters, as defined by Kuhl and van Hasselt (1822) and Delorme et al. (2006): (1) pointed snout profile bearing a pointed projection, protruding laterally beyond the lower jaw; (2) broad and flattened eyelid with a palpebral projection; (3) possession of a broad and depressed head; (4) conical spine at the corner of the mouth; (5) vertical pupil; (6) and presence of maxillary and vomerine teeth. Megophrys selatanensis sp. nov. can be diagnosed from geographically proximate congeners from the Sunda Shelf and the Philippines by the following combination of morphological characters: large body, stocky (SVLh 79.3 mm in adult female); snout acute with short rostral appendage (RSAL 0.3% in adult female); relatively short triangular palpebral projection with acute tip (EHL 21.3% UEWh in adult female); head wider than long (HW 126.4% HLh in adult female); tympanum distinct, vertically elongated (TDH 52.4% TDV in adult female); vomerine teeth present; a pair of dorsolateral folds extending from shoulder above axilla to groin; dorsal skin smooth with low and dense tuberculation; ventral skin smooth from throat to belly; short thigh (RTL 40.3% in adult female), foot nearly as long as the thigh (FL 99.4% TL in adult female); tibiotarsal articulation reaching posterior corner of eye; toes webbed at base.

Description of holotype (measurements in mm). Adult female, large body size (SVLh 79.3; SVL 79.1) and habitus stocky; head depressed and broad, wider (HW 38.1, 48.0% SVLh) than long (HL 30.6, 38.6% SVLh); snout short (SL 9.4, 11.9% SVLh), pointed at tip, acute, with very short rostral appendage (SAL 0.3% SVLh), laterally protruding and projecting beyond lower jaw; nostril positions laterally, closer to tip than to snout; eye positioned laterally, large, over three and a half times horizontal diameter of tympanum (ED 9.9, 365.1% TDH), eye diameter (ED 9.9, 12.5% SVLh) as long as snout-horn length (SLh 9.8, 12.3% SVLh), about twice nostril-eye length (ED 210.6% NEL), pupil vertical elliptical; canthus rostralis with sharp and angular ridge, lore sloping and concave; internarial distance (IND 7.6, 9.6% SVLh) more than half of interorbital distance (IND 66.7% IOD); palpebral projection length about 0.2 times of total upper eyelid width (EHL 1.8, 21.3% UEWh), tip acute, surface smooth; upper eyelid edges with scattered small and low conical tubercles; tympanum distinct, smooth, oval, elongated vertically (TDH 2.7, 3.4% SVLh; TDV 5.2, 6.5% SVLh; TDH 52.4% TDV); angular supratympanic fold, distinct, extending from behind eye, curving down around upper border of tympanum and ending above axilla; white conical tubercles present behind supratympanic fold and front of axilla; spinous gland on the corner of mouth on jaw angle; single row of maxillary teeth present; vomerine teeth present in two widely separated groups, at the level of posterior borders of choana; tongue lanceolate, notched posteriorly, without papillae.

Forelimb slender, short, hand length about half of arm length (HAL 21.3, 55.9% LAL), lower and upper arms slender; fingers moderately slender with rounded and swollen tips, unwebbed, lacking lateral fringes, finger length formula II=IV<I<III (fin2L 7.4, 9.3% SVLh; fin4L 7.4, 9.3% SVLh; fin1L 8.1, 10.2% SVLh; and fin3L 10.0, 12.6% SVLh); subarticular tubercles absent; outer palmar tubercle smaller than inner palmar tubercle (OPTL 3.9, 4.9% SVLh; IPTL 7.2, 9.0% SVLh).

Hindlimb slender, moderately long (HLL 106.8, 134.7% SVLh), thigh (FML 36.7, 46.3% SVLh) slightly longer than tibia (TL 32.0, 40.1% SVLh), about twice of tarsus length (TSL 17.6, 22.2% SVLh), and nearly as long as foot (FL 31.8, 40.1% SVLh); toe length formula I<II<V<III<IV (Toe1L 4.6, 5.8% SVLh; Toe2L 5.6, 7.0% SVLh; Toe5L 7.9, 9.9% SVLh; Toe3L 8.9, 11.3% SVLh; and Toe4L 17.5, 22.1% SVLh); tibiotarsal articulation reaching to posterior corner of eye; inner metatarsal tubercle moderately large (IMTL 5.8, 7.4% SVLh), outer absent; subarticular tubercles absent, toes with rounded and swollen tips, webbed only at base.

Dorsal skin smooth, with low and dense tubercles, mostly on forelimbs, hindlimbs, and flanks; a pair of distinct dorsolateral folds, one on each side, extending from shoulder, above axilla to groin; vent without dorsal dermal accessory extension; three transverse folds on lower arm; five transverse folds on hindlimb, three on thigh and two on tibia; limbs skin laterally smooth, with small tubercles; ventral skin smooth, wrinkled in preservative; pair of white conical pectoral glands at base of axilla; a white conical femoral gland at mid flanks of posterior thigh.

Coloration. In life ( Fig. 2A–B View FIGURE 2 ): pupil dark, iris golden-brown; base colour of dorsum uniform light brown; dorsal surface of forearm, hand, and hindlimbs slightly lighter than dorsum; upper limbs with dark brown transverse folds, three on forearm, three on thigh, and two on tarsus, fingers with dark brown crossbars, one on first and second fingers, two on third and fourth fingers; knee with irregular dark spots; dorsal surface and lateral sides of head light brown, with dark spots on upper and lower lips, from jaw angle to tip of snout; skin around eyes dark brown; flanks light brown, brighter than dorsum, unmarked; ventral surface light brown, with darker throat and chest; longitudinal markings over throat to pectoral region and dark blotches on belly; light brown blotches on ventral of limbs, with dark brown pattern near the joint between hand and lower arm. In preservative, dorsal surface darker, lateral and ventral surfaces fading to whitish, but pattern remains ( Fig. 3A–E View FIGURE 3 ).

Variation. Type and referred specimens are morphometrically similar, despite large ontogenetic discrepancy between the adult female holotype ( MZB. Amph 22411), subadult male paratype (UTA A-66176), largest juvenile referred specimen (UTA A-66177), and smaller juvenile referred specimen ( MZB. Amph 32593). The adult specimen has slightly shorter rostral and palpebral projections, a shorter head, and shorter limbs, as compared to the subadult and juvenile specimens. The tibiotarsal joint, when the hindlimbs are adpressed forward, reaches the posterior corner of the eye in the adult and subadult, but only reaches the mid-eye in the juvenile. The morphometric variation is given in Table 2 View TABLE 2 .

In coloration, the dorsum of the subadult paratype (UTA A-66176, Fig. 2B View FIGURE 2 ) and the referred specimen (UTA A-66177, Fig. 2E View FIGURE 2 ) is brighter than that of the holotype, this is darker in the smaller referred specimen ( MZB Amph 32593, Fig. 2F View FIGURE 2 ). An irregular brighter brown pattern below the canthus rostralis is present in the paratype and the referred specimens but, it is absent in the holotype ( Fig. 2A, C, E–F View FIGURE 2 ). The paratype and referred specimens have a dark inverted triangle pattern on the parietal-orbital-scapular region. The paratype has orange-reddish coloration on the throat, chest, and ventral surface of the fingers and toes ( Fig 2C, D View FIGURE 2 ). The juvenile specimens ( MZB Amph 32593 and UTA A-66177) have darker brown throats and chests .

Comparisons. Megophrys selatanensis sp. nov. is morphologically most similar to M. montana than to other geographically related congeners. Megophrys selatanensis sp. nov. has elongated dorsolateral folds that extend from the parietoscapular region to the groin, type I, as M. montana , M. parallela , M. lancip , M. nasuta , M. kalimantanensis Munir, Hamidy, Matsui, Iskandar, Sidik, and Shimada , and M. stejnegeri Taylor. Megophrys selatanensis sp. nov. differs from M. montana by having a shorter rostral appendage—SAL 0.3−0.6% SVLh (vs. SAL reaching 3.5% SVLh: Munir et al., 2018), shorter palpebral projection—EHL 21.3–24.3% UEWh (vs. reaching 48.4% UEWh: Munir et al., 2018), shorter ratio of foot to thigh—FL 96.6−99.4% TL (vs. FL 106.2−115.6% TL: Munir et al., 2018), and toes webbed only at base (vs. more developed web on second to fifth toes: Munir et al., 2018). Megophrys selatanensis sp. nov. differs from M. parallela by having elongated dorsolateral folds reaching the groin (vs. only reaching two-thirds of trunk), females being large—known adult female 79.1 mm SVL (vs. SVL ≤ 58.3 mm: Munir et al., 2018), a rostral appendage present (vs. absent: Inger and Iskandar, 2005; Munir et al., 2018), shorter ratio of foot to thigh—FL 96.6–99.4% TL (vs. FL 105.4–112.5% TL: Munir et al., 2018). The new species differs from M. lancip by having a less developed rostral appendage—SAL 0.3−0.6% SVLh (vs. SAL 1.4–4.1% SVLh: Munir et al., 2018), a shorter head length—HLh 38.0–38.5% SVLh (vs. HLh 42.1–44.6% SVLh: Munir et al., 2018), slightly wider head ratio to its length—HW 119.3–126.4% HLh (vs. HW 103.2–116.0% HLh: Munir et al., 2018), relatively shorter ratio of feet to thigh—FL 96.6–99.4%TL (vs. FL 102.5–109.8% TL: Munir et al., 2018), toes webbed only at base (vs. rather developed on third, fourth and fifth toes: Munir et al., 2018).

Megophrys selatanensis sp. nov. differs from M. nasuta by the absence of additional lateral folds on flanks (vs. presence: Munir et al., 2018, 2019), shorter acute rostral appendage—SAL 0.3−0.6% SVLh (vs. acuminate rostral appendage, SAL 1.8−9.2% SVLh: Munir et al., 2019), shorter acute palpebral projection—EHL 2.2−3.4% SVLh (vs. acuminate palpebral projection, EHL 4.4−13.0% SVLh: Munir et al., 2019), shorter snout to nostril length—SNLh 3.7−5.1% SVLh (vs. SNLh 5.1−13.8% SVLh: Munir et al., 2019), shorter head length—HLh 38.0−40.5% SVLh (vs. HLh 39.5−51.7.% SVLh: Munir et al., 2019), smaller ratio of palpebral projection to upper eyelid width—EHL 21.3−25.7% UEWh (vs. EHL 32.7−61.4% UEWh: Munir et al., 2019), and relatively wider head—HW 119.3−126.4% HLh (vs. HW 92.9−119.5% HLh: Munir et al., 2019). From M. kalimantanensis , the new species differs by the absence of additional lateral folds on flanks (vs. presence: Munir et al., 2019), female being smaller—known adult female 79.1 mm SVL (vs. 109.1−116.4 mm SVL: Munir et al., 2019), adpressed tibiotarsal articulation reaching posterior corner of eye in female (vs. posterior of tympanum, in female: Munir et al., 2019). From M. stejnegeri Taylor , Megophrys selatanensis sp. nov. differs by having the dorsolateral folds extending to the groin (vs. maximum of two-thirds length of trunk: Inger, 1954), female being slightly larger—known adult female 79.1 mm SVL (vs. SVL 57.0– 77.8 mm: Taylor, 1920; Inger 1954), a rostral appendage present (vs. absent: Taylor, 1920; Inger, 1954), vomerine teeth present (vs. absent: Taylor, 1920; Inger, 1954), tympanum vertically elongated (vs. slightly rounded, see figure 37 by Diesmos et al., 2015 and figure 18 by Sanguila et al., 2016), and smooth skin on the temporal region (vs. tuberculate, see figure 37 by Diesmos et al., 2015 and figure 18 by Sanguila et al., 2016).

Megophrys selatanensis sp. nov. is distinguished from M. kobayashii Malkmus and Matsui by having type I dorsolateral folds (vs. dorsolateral folds extended from parietoscapular region to mid-body, type II, see Table 3 View TABLE 3 ), additional lateral folds on flanks absent (vs. present: Malkmus and Matsui, 1997; Munir et al., 2018), female being smaller—known adult female 79.1 mm SVL (vs. SVL 99.0–109.0 mm: Malkmus and Matsui, 1997; Inger and Stuebing, 2005), a rostral appendage present (vs. absent: Malkmus and Matsui, 1997), and smaller and fewer tubercles on the body flanks (vs. larger and numerous: Malkmus and Matsui, 1997). From M. ligayae Taylor , the new species differs in having type I dorsolateral folds (vs. type II: Taylor, 1920; Inger, 1954; Munir et al., 2018), no additional lateral folds on flanks (vs. present: Taylor, 1920; Inger, 1954; Munir et al., 2018), female being smaller—known adult female 79.1 mm SVL (vs. SVL 90.0 mm: Inger, 1954), tibiotarsal articulation reaching posterior corner of eye (vs. tympanum: Taylor, 1920), and toes webbed only at base (vs. rather developed web on third, fourth, and fifth toes, see figure 37C Diesmos et al., 2015). From M. edwardinae Inger , the new species differs by having type I dorsolateral folds (vs. absent: Inger, 1989), a rostral appendage present (vs. absent: Inger, 1989), vomerine teeth present (vs. absent: Inger, 1989), and smooth dorsal skin surface with low and dense tubercles (vs. dorsal surface with scattered round and elongated tubercles: Inger, 1989). Megophrys selatanensis sp. nov. can be distinguished from M. baluensis Boulenger by having type I dorsolateral folds (vs. dorsolateral folds formed by a series of elongated tubercle, type III: Inger and Stuebing, 2005: Munir et al., 2018), female being slightly larger—known adult female 79.1 mm SVL (vs. SVL ≤ 70 mm: Inger, 1966; Inger et al., 1995), a rostral appendage present (vs. absent: Boulenger, 1899; Inger, 1966; Inger et al., 1995), having a triangular palpebral projection (vs. small palpebral projection like tubercle: Inger, 1989; Inger et al., 1995), having smaller and fewer tubercles on body flanks (vs. larger and numerous: Inger et al., 2017), and adpressed tibiotarsal articulation reaching posterior of eye (vs. shoulder: Boulenger, 1899).

Megophrys selatanensis sp. nov. differs from M. dringi Inger, Stuebing, and Tan , M. aceras Boulenger , and M. longipes Boulenger by the absence of Y, X,>–<or H shaped folds on dorsal (vs. presence: Boulenger, 1885, 1903; Inger et al., 1995, see Table 3 View TABLE 3 ). Furthermore, from M. dringi the new species being larger in female—known adult female 79.1 mm SVL (vs. SVL 55 mm: Inger et al., 1995; Inger and Stuebing, 2005), having a stocky body (vs. slender: Inger et al., 1995), a rostral appendage present (vs. absent: Inger et al., 1995), having a triangular palpebral projection (vs. small like tubercle: Inger et al., 1995), vomerine teeth present (vs. absent: Inger et al., 1995), distinct tympanum (vs. partially obscured: Inger et al., 1995). The new species differs from M. aceras by having a stocky body (vs. slender: Boulenger, 1903), a rostral appendage present (vs. absent: Boulenger, 1903), tibiotarsal articulation reaching to posterior corner of eye (vs. shoulder, angle of jaws or temporal area: Taylor, 1962), and toes webbed only at base (vs. rather possessing developed web between third, fourth, and fifth toes: Taylor, 1962; see figure 5 in Munir et al., 2018). From M. longipes , the new species differs being larger in female—known adult female 79.1 mm SVL (vs. SVL 49.0–65.0 mm: Inger et al., 1995), having a stocky body (vs. slender: Boulenger, 1885), a rostral appendage present (vs. absent: Boulenger, 1885), having a triangular palpebral projection (vs. small like tubercle: Boulenger, 1885; Taylor, 1962), shorter thigh—TL 0.41−0.44 SVL (vs. TL 0.54–0.65 SVL: Inger et al., 1995; Inger and Iskandar, 2005) and tibiotarsal articulation reaching posterior corner of eye (vs. far beyond tip of snout: Boulenger, 1885; Taylor, 1962).

Distribution and natural history. The holotype and one referred specimen (MZB Amph 32593) were collected in leaf litter on the edge of an old secondary forest in proximity to a coffee plantation and above a geothermal station in the province of Lampung, while the paratype (UTA A-66176) and the other referred specimen (UTA A- 66177) were collected from an old secondary forest in the green corridor between the Gunung Patah and Gunung Agung. These locations are about 170 km apart along the eastern slope of the southern Barisan range of Sumatra. The tadpoles (ENS 14306 and ENS 14737) were collected from a small rocky stream in the old secondary forest near Lake Ranau, Lampung, 1108–1487 m a.s.l. (description of the tadpole of this new species is pending as we are preparing another manuscript to present detailed description of Sumatran Megophrys tadpoles). Most of the samples of M. selatanensis sp. nov. were collected from a small patched forest area in the eastern Bukit Barisan Selatan Mountain ranges, which is threatened by high deforestation. The exact distribution, population, breeding behavior, call, and other ecological information are unknown. The following anuran species have been found sympatrically with the new species, at Ngarip, Lampung: Indosylvirana nicobariensis (Stoliczka) ; Chalcorana chalconota (Schlegel) ; Wijayarana sumatrana (Yang) ; Hylarana erythraea (Schlegel) ; Ingerophrynus biporcatus (Gravenhorst) ; Leptophryne borbonica (Tschudi) ; Limnonectes kuhlii (Tschudi) ; L. macrodon (Duméril and Bibron) ; Limnonectes sp. ; Microhyla gadjahmadai Atmaja, Hamidy, Arisuryanti, Matsui, Smith ; M. palmipes Boulenger ; Pelophryne sp. ; Philautus larutensis (Boulenger) ; P. polymorphus Wostl, Riyanto, Hamidy, Kurniawan, Smith, and Harvey ; P. thamyridion Wostl, Riyanto, Hamidy, Kurniawan, Smith, and Harvey ; Phrynoides asper (Gravenhorst) ; Polypedates leucomystax (Gravenhorst) ; Rhacophorus achantharrhena Harvey, Pemberton, and Smith ; R. catamitus Harvey, Pemberton, and Smith ; and R. poecilonotus Boulenger ; at the foothills of Gunung Patah, Sumatra Selatan: Wijayarana sumatrana ; Limnonectes sp. ; Microhyla sp. ; Nyctixalus pictus (Peters) ; Philautus polymorphus ; P. thamyridion ; P. ventrimaculatus Wostl, Riyanto, Hamidy, Kurniawan, Smith, and Harvey ; Phrynoides asper ; Rhacophorus catamitus ; and R. poecilonotus .