Genetic Variation of Baram River Frog, Pulchrana baramica (Boettger, 1900), In Java, Sumatra, and Kalimantan based on 16S Mitochondrial Gene

Baram River Frog (Pulchrana baramica) is a ranid species distributed in the Malay Peninsula, Borneo, Sumatra and represents the sole species from the genus Pulchrana on Java Island. Cryptic species are commonly encountered within the amphibian group which can cause confusion in the identification process. Due to the broad distribution range of P. baramica and the frequent occurrence of cryptic species within the amphibian group, it is important to evaluate the taxonomic status of P. baramica. Therefore, we investigated the taxonomic position of P. baramica from three populations (Kalimantan, Sumatra, and Java) and identified the interpopulation genetic variation based on molecular data of the 16S mitochondrial gene. We reconstructed phylogenetic relationships using Neighbour Joining, Maximum Likelihood, and Bayesian Inference. The research results revealed that Pulchrana baramica is a monophyletic group and nested within a group together with P. glandulosa and P. laterimaculata. The monophyletic group of P. baramica consisted of four distinct lineages that molecularly showed interspecific genetic variation. Clade 1 represents the population of Sumatra and Borneo (Kalimantan), clade 2 comprises the population from Borneo (Sarawak), clade 3 consists of population from Java, and clade 4 represents the population from Sumatra. Further research is required with the addition of morphological and acoustic data as supportive evidence to obtain more extensive comprehension of species identification

Morphological characters review on white-lipped frog (Chalcorana chalconota; Schelgel, 1837) based on morphometrical analysis, within the population of Java

Abstract Chalcorana chalconota or White-Lipped Frogs are widely distributed in Indonesia, Malaysia, and Thailand. Described as a species complex, C. chalconota from Java Island is very necessary to be studied its taxonomic status. Intra-population studies are important to determine the representation of a population in a particular place. Therefore, we have aimed to elaborate on the relationship of C. chalconota within the Java population using a morphometric approach. This research was conducted in the Laboratory of Herpetology, Research Center for Biology, Indonesian Institute of Sciences. Morphometric measurements were performed totally on 47 individuals of C. chalconota from Java Island with 29 morphological characters. Data analyses using Principal Component Analysis (PCA) and cluster analysis with Bray-Curtis Index. PCA on both sexes investigated a random grouping, both samples from West Java, Central Java, East Java, and Banten. Clustering analyses on male and female population are indicating high indexed of Bray Curtis with score up to 0.9, means very closely related among individual. Such as PCA, clustering analysis produces the same grouping patterns (random) from different localities. Based on PCA and clustering analysis, we interpreted that C. chalconota in the Javanese population was closely related with evidence of conserved morphological characters.</jats:p

Two new species of Megophrys Kuhl and Van Hasselt (Amphibia: Megophryidae) from Sumatra, Indonesia

We evaluated the taxonomic status of the genus Megophrys in Sumatra using molecular and morphological data. Mitochondrial phylogenetic inference and morphological data revealed two undescribed species, one in southern Sumatra—M. selatanensis sp. nov. and one in northern Sumatra—M. acehensis sp. nov. We also detected a potential cryptic species within M. parallela, but refrain from describing this lineage here due to insufficient data. Genetic variation within Sumatran Megophrys is highly structured and will require additional geographic sampling to understand the interplay between geography and genetics in Sumatran Megophrys.&#x0D;  </jats:p

Megophrys acehensis Munir & Nishikawa & Hamidy & Smith 2021, sp. nov.

&lt;i&gt;Megophrys acehensis&lt;/i&gt; sp. nov. &lt;p&gt;(Figs. 4 A&minus;D, 5A&minus;E)&lt;/p&gt; &lt;p&gt; &lt;b&gt;Holotype&lt;/b&gt; MZB. Amph 26098 (field number ENS 18664; GenBank accession no. MT 710708; Figs. 4 A&minus;B, 5A&minus;E; &lt;i&gt;Megophrys&lt;/i&gt; sp. north in Fig. 1 and Table 1), adult male collected at 2330 h on 5 August 2015 from Aceh Province, Aceh Tengah Regency, Linge District, Kute Robel (4.506444 &deg;N, 96.860750 &deg;E, 1638 m a.s.l), by Elijah Wostl, Ilham Fonna, and Muhammad Iksan (Fig. 6).&lt;/p&gt; &lt;p&gt; &lt;b&gt;Paratype&lt;/b&gt; UTA A&ndash;66178 (field number ENS 21030; GenBank accession no. MT 710709; Fig. 4C&ndash;D), a sub adult male collected on at 1856 h on 1 June 2016 from Aceh Province, Pidie Regency, Geumpang District, UPT V Geumpang (4.854540 &deg;N, 96.216540 &deg;E, 1086 m a.s.l) by Michael B. Harvey and Eric N. Smith (Fig. 6).&lt;/p&gt; &lt;p&gt; &lt;b&gt;Etymology.&lt;/b&gt; The specific name &lt;i&gt;acehensis&lt;/i&gt; is derived from the province of Aceh in northern Sumatra and the Latin suffix&ndash; &lt;i&gt;ensis&lt;/i&gt; meaning from that place.&lt;/p&gt; &lt;p&gt; &lt;b&gt;Suggested English common name.&lt;/b&gt; Aceh Horned Frog&lt;/p&gt; &lt;p&gt; &lt;b&gt;Suggested Indonesian name.&lt;/b&gt; Katak&ndash;tanduk Aceh&lt;/p&gt; &lt;p&gt; &lt;b&gt;Diagnosis.&lt;/b&gt; The new species was assigned to the genus &lt;i&gt;Megophrys&lt;/i&gt; based on the combination of the following morphological characters, as defined by Kuhl and van Hasselt (1822) and Delorme &lt;i&gt;et al&lt;/i&gt;. (2006): (1) pointed snout profile, bearing a pointed projection, protruding laterally beyond the lower jaw; (2) broad and flattened eyelid with palpebral projection; (3) possession of a broad and depressed head; (4) conical spine at the corner of mouth; (5) vertical pupil; (6) presence of maxillary and vomerine teeth. &lt;i&gt;Megophrys acehensis&lt;/i&gt; &lt;b&gt;sp. nov.&lt;/b&gt; can be diagnosed from its geographically relevant congeners in the Sunda Shelf and the Philippines by the following combination of characters: medium body size, stocky (SVLh 38.1 mm in adult male); snout pointed with a short, acute rostral appendage (RSAL 1.3% in adult male); relatively short triangular palpebral projection with acute tip (EHL 25.1% UEWh in adult male); head length relatively short (RHLh 37.2% in adult male); head wider than its long (HW 113.6% HLh in adult male); tympanum distinct, about one-third of eye diameter (TDH 35.6% ED in adult male), nearly rounded (TDH 85.9 % TDV in adult male); vomerine teeth present; a pair of dorsolateral folds, extending from shoulder, above axilla to groin; dorsal and lateral skin tuberculate, shagreened on the throat to belly; short lower arm (RLAL 45.8% in adult male); foot nearly as long as thigh (FL 96.6% TL in adult male); tibiotarsal articulation reaching posterior of eye; toe webbing absent.&lt;/p&gt; &lt;p&gt; &lt;b&gt;Description of holotype (measurements in mm).&lt;/b&gt; Adult male, medium body size (SVLh 38.1, SVL 37.4) and habitus stocky; head depressed and broad, wider (HW 16.4, 42.9% SVLh) than long (HL 13.3, 34.9% SVLh); snout short (SL 4.2, 11.1% SVLh), pointed at tip with acute short rostral appendage (SAL 0.7, 1.8% SVLh), laterally protruding and projecting beyond lower jaw; nostril positioned laterally, near to snout than to eye; eye positioned laterally, large, nearly three times of tympanum horizontal diameter (ED 5.5, 280.5% TDH), eye diameter slightly wider (ED 5.5, 14.4% SVLh) than snout&ndash;horn length (SLh 5.4, 14.2% SVLh), about two and three-quarter times of nostril&ndash;eye length (ED 275% NEL), pupil vertical elliptical; canthus rostralis with sharp, angular ridge, lore sloping and concave; internarial distance (IND 4.0, 10.4% SVLh) about two-thirds of interorbital distance (IND 68.4% IOD); palpebral projection length about one-quarter of total upper eyelid width (EHL 1.2, 25.1% UEWh), tip acute, surface smooth and scattered with small and low tubercles; tympanum distinct, smooth, oval, slightly rounded (TDV 2.3, 6.0% SVLh; TDH 2.0, 5.1% SVLh; TDH 85.9% TDV); angular supratympanic fold, distinct, widened anteriorly, narrowed posteriorly, extending from behind eye, curving down around upper border of tympanum and ending above axilla; white conical tubercles behind the supratympanic fold and anterior to axilla; spinous gland on corner of mouth on jaw angle; single row of maxillary teeth present; vomerine teeth in two widely separated groups, at level posterior borders of choana; tongue lanceolate, notched posteriorly, without papillae; median subgular vocal sac present, having slit&ndash;like opening on each side of jaw commissures.&lt;/p&gt; &lt;p&gt;* Fold forming Y, X or H on the parietoscapular region to the level of axilla; ** Dorsolateral fold shape: dorsolateral folds are elongated and extend from the parietoscapular region to the groin (Type I); dorsolateral folds extend from the central of parietoscapular region to mid-body (Type II); multiple dorsolateral folds - at least three or four - and they are discontinuous, formed by a series of elongated tubercles (Type III); dorsolateral folds are elongated and curve from the axillary region towards (and reaching) the posterior dorsal margin of tympanum (Type IV).&lt;/p&gt; &lt;p&gt;Forelimb slender and short, hand length about half of arm length (HAL 9.5, 54.3% LAL), lower arm proximally enlarged, wider than upper arm; fingers moderately slender, with rounded and swollen tips, unwebbed and lacking of lateral fringes; finger length formula I&lt;II&lt;IV&lt;III (fin1L 2.6, 6.9% SVLh; fin2L 3.2, 8.4% SVLh; fin4L 3.5, 9.2% SVLh; and fin3L 4.9, 12.8% SVLh); subarticular tubercles absent; outer palmar tubercle smaller than inner (OPTL 1.9, 5.0% SVLh; IPTL 2.5, 6.6% SVLh).&lt;/p&gt; &lt;p&gt;Hindlimb slender, moderately long (HLL 52.0, 136.5% SVLh), thigh (FML 17.1, 44.8% SVLh) slightly longer than tibia (TL 15.4, 40.4% SVLh), about twice of tarsus length (TSL 8.5, 22.3% SVLh), and nearly as long as foot (FL 14.9, 39.1% SVLh); toe length formula I&lt;II&lt;V&lt;III&lt;IV (Toe1L 2.1, 5.4% SVLh; Toe2L 3.3, 8.6% SVLh; Toe5L 4.5, 11.8% SVLh; Toe3L 4.6, 12.0% SVLh; and Toe4L 7.8, 20.6% SVLh); tibiotarsal articulation reaching to posterior corner of eye; inner metatarsal tubercle moderately large (IMTL 2.0, 5.1% SVLh), outer absent; subarticular tubercles absent, toes with rounded and swollen tips, toes web absent.&lt;/p&gt; &lt;p&gt;Dorsal skin surface tuberculate, low dense tubercles in entire dorsal and larger-sized tubercles mostly on forelimb, hindlimb, flanks and groin, shagreened in preservative; a pair of dorsolateral folds present, one on each side, extending from shoulder above the axilla to groin; vent with dorsal dermal accessory extension; transverse folds on limbs present, three on lower arm, three on thigh and three on tibia; limbs skin laterally tuberculate, larger size of tubercles than on dorsal side; ventral skin smooth shagreened on throat to chest, but smooth on belly and limbs, wrinkled in preservative; a pair of white conical pectoral glands, at base of axilla; white conical femoral glands, at the mid flanks of the posterior thigh; dark brown microspinules nuptial pads covering dorsal and median surfaces of the distal half of metacarpal and proximal half of basal phalanx of first and second fingers.&lt;/p&gt; &lt;p&gt; &lt;b&gt;Coloration.&lt;/b&gt; In life (Fig. 4A&ndash;B, 5A&ndash;B), pupil dark, iris golden&ndash;brown, base of dorsum immaculate dark brown with indistinct dark brown inverted triangle pattern on parieto-orbital to scapular region and inverted &ldquo;V&rdquo; like pattern on back, positioned closer to vent than to parietal region; dorsal surface of head, forelimb and hindlimb darker than lateral body; dark brown transverse folds present on dorsal surface of forearm, thigh and tibia, two on the forearm, three on thigh and three on tibia, fingers with dark brown crossbars, one on first and second fingers, two on third and fourth fingers; dorsomedial surfaces of first and second fingers with dark brown microspinular nuptial pads; knee with irregular dark brown spots; dorsal surface and lateral sides of head dark brown, irregular lighter brown pattern below canthus rostralis, light brown on underside of eyelids; body flanks dark brown and unmarked, lighter than dorsum; forelimb flanks dark brown, as dorsum; hindlimb flanks cream with dark brown blotches; ventral surface from throat to chest dark brown with heavy dark longitudinal marking; belly and underside of fore- and hindlimbs light cream with dark brown blotches; in preservative, pattern remains, but dorsal, lateral, and ventral surfaces are darker (Fig. 5C).&lt;/p&gt; &lt;p&gt; &lt;b&gt;Variation.&lt;/b&gt; The two type specimens are morphometrically similar. The holotype has slightly longer rostral appendage, head, and snout-nostril and snout lengths, but a slightly shorter palpebral projection, and a thicker and narrower head. Morphometric variation is shown in Table 2. The transverse fold in the occipital region varies in degree of development, being distinct on the holotype but indistinct on the paratype. The dorsal coloration in life is dark brown on the holotype and orange-brown on the paratype. The ventral color of the two specimens is marbled with brown in both specimens but, the background color of the holotype is cream anteriorly and light grey posteriorly while that of the paratype is dark orange anteriorly and whitish posteriorly (Fig. 4 A&minus;D).&lt;/p&gt; &lt;p&gt; &lt;b&gt;Comparisons.&lt;/b&gt; &lt;i&gt;Megophrys acehensis&lt;/i&gt; &lt;b&gt;sp. nov.&lt;/b&gt; differs from its most similar congener, &lt;i&gt;M. parallela&lt;/i&gt; by having dorsolateral folds extending to the groin (vs. maximum of two-thirds length of trunk: Inger and Iskandar, 2005; Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), a rostral appendage present (vs. absent: Inger and Iskandar, 2005; Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), shagreened ventral surface from throat to belly (vs. smooth: Inger and Iskandar, 2005; Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), and a relatively shorter foot to thigh ratio&mdash;FL 92.1&minus;96.6% TL (vs. 105.4&minus;112.5% TL: Munir &lt;i&gt;et al.,&lt;/i&gt; 2018). From &lt;i&gt;M. montana,&lt;/i&gt; the new species differs by having tuberculate dorsal skin surface (vs. smooth: Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), shagreened skin on throat (vs. smooth: Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), a relatively short foot to thigh ratio&mdash;FL 92.1&minus;96.6% TL (vs. FL 106.2&minus;115.6% TL: Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), and absent toe webbing (vs. rather developed webbing from second to fifth toes: Munir &lt;i&gt;et al.,&lt;/i&gt; 2018). From &lt;i&gt;Megophrys selatanensis&lt;/i&gt; &lt;b&gt;sp. nov.&lt;/b&gt;, &lt;i&gt;Megophrys acehensis&lt;/i&gt; &lt;b&gt;sp. nov.&lt;/b&gt; differs by having a longer rostral appendage&mdash;SAL 1.3&ndash;1.8% SVLh (vs. SAL 0.3&minus;0.6% SVLh), a slightly longer palpebral projection &mdash;EHL 25.1&ndash;28.4% UEWh (vs. EHL 21.3&ndash;24.3% UEWh), slightly narrower ratio of head width to its length&mdash;HW 114.1&minus;115.3% HLh (vs. HW 119.3&minus;126.4% HLh), wider ratio of tympanum to eye diameter&mdash;TDH 35.6&minus;37.5% ED (vs. TDH 27.3&minus;28.5% ED), tympanum nearly rounded&mdash;TDH 85.9&ndash;93.8 TDV (vs. vertically elongated, TDH 46.5&minus;61.9% TDV), slightly shorter lower arms&mdash;LAL 44.8&ndash;45.8% SVLh (vs. LAL 48.0&ndash;49.2% SVLh), tuberculate dorsal skin surface (vs. smooth), shagreened skin on throat (vs. smooth), and absent toe webbing (vs. toes webbed at base). &lt;i&gt;Megophrys acehensis&lt;/i&gt; &lt;b&gt;sp. nov.&lt;/b&gt; differs from &lt;i&gt;M. lancip&lt;/i&gt; by males having a shorter rostral appendage&mdash;SAL 1.3&minus;1.8% SVLh (vs. SAL 2.9&minus;3.1% SVLh in males, but overlapped with females SAL 1.4&minus;4.1% SVLh: Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), shorter head length&mdash;HLh 37.2&ndash;37.8% SVLh (vs. HLh 42.1&ndash;44.6% SVLh; Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), wider head in males&mdash;HW 114.1&ndash;115.3% HLh (vs. HW 103.2&ndash;105.8% HLh in males, but overlapped with females HW 110.6&ndash;116.0% HLh: Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), wider tympanum relative to eye diameter&mdash;TDH 35.6&minus;37.5% ED (vs. TDH 25.7&minus;28.0 ED: Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), tympanum nearly rounded&mdash;TDH 85.9&ndash;93.8 TDV (vs. vertically elongated, TDH 61.1&minus;69.1% TDV), relatively short foot to thigh ratio&mdash;FL 92.1&minus;96.6% TL (vs. FL 102.5&minus;109.8% TL; Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), and toe webbing absent (vs. rather developed on first to fifth toes, see Figs. 4D, I, 5B in Munir &lt;i&gt;et al.,&lt;/i&gt; 2018).&lt;/p&gt; &lt;p&gt; &lt;i&gt;Megophrys acehensis&lt;/i&gt; &lt;b&gt;sp. nov.&lt;/b&gt; differs from &lt;i&gt;M. nasuta&lt;/i&gt; by the absence of additional lateral flank folds (vs. presence: Munir &lt;i&gt;et al.,&lt;/i&gt; 2018, 2019), males being smaller&mdash;known adult male 37.4 mm SVL (vs. SVL 66.0&ndash; 93.4 mm: Munir &lt;i&gt;et al.,&lt;/i&gt; 2019), shorter acute rostral appendage&mdash;SAL 1.3&minus;1.8% SVLh (vs. acuminate rostral appendage, SAL 1.8&minus;9.2% SVLh: Munir &lt;i&gt;et al.,&lt;/i&gt; 2019), and shorter acute palpebral projection&mdash;EHL 25.1&minus;28.4% UEWh (vs. acuminate palpebral projection, EHL 32.7&minus;61.4% UEWh: Munir &lt;i&gt;et al.,&lt;/i&gt; 2019). From &lt;i&gt;M. kalimantanensis,&lt;/i&gt; the new species differs by the absence of additional flank folds (vs. present: Munir &lt;i&gt;et al.,&lt;/i&gt; 2019), smaller body size in males&mdash;known adult male 37.4 mm SVL (vs. SVL 64.3&ndash;100.6 mm: Munir &lt;i&gt;et al.,&lt;/i&gt; 2019), slightly longer rostral appendage&mdash;SAL 1.3&minus;1.8% SVLh (vs. SAL 0.1&minus;0.8% SVLh: Munir &lt;i&gt;et al.,&lt;/i&gt; 2019), and shorter palpebral projection&mdash;EHL 25.1&minus;28.4% UEWh (vs. 30.9&minus;53.2% UEWh: Munir &lt;i&gt;et al.,&lt;/i&gt; 2019). From &lt;i&gt;M. stejnegeri,&lt;/i&gt; the new species differs by having dorsolateral folds extending to the groin (vs. maximum of two-thirds the length of the trunk: Inger 1954), males being smaller&mdash;known adult male 37.4 mm SVL (vs. adult male 40.6&minus;60.0 mm: Taylor, 1920; Inger, 1954), vomerine teeth present (vs. absent: Taylor, 1920; Inger &lt;i&gt;et al.,&lt;/i&gt; 1954), and smooth skin on the posterior of tympanum (vs. tuberculate, see figure 37 by Diesmos &lt;i&gt;et al.,&lt;/i&gt; 2015 and figure 18 by Sanguila &lt;i&gt;et al.,&lt;/i&gt; 2016).&lt;/p&gt; &lt;p&gt; &lt;i&gt;Megophrys acehensis&lt;/i&gt; &lt;b&gt;sp. nov.&lt;/b&gt; can be distinguished from &lt;i&gt;M. kobayashii&lt;/i&gt; by having type I dorsolateral folds (vs. type II, see Table 3), absent additional lateral flank folds (vs. present: Malkmus and Matsui, 1997; Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), males being smaller&mdash;known adult male 37.4 mm SVL (vs. 93.0&minus;101.0 mm: Inger and Stuebing, 2005), rostral appendage present (vs. absent: Malkmus and Matsui, 1997), and smaller and fewer tubercles on flanks (vs. larger and numerous: Malkmus and Matsui, 1997). From &lt;i&gt;M. ligayae&lt;/i&gt;, the new species differs by having type I dorsolateral folds, extended to the groin (vs. type II, reaching a maximum of two-thirds of trunk: Taylor, 1920; Inger, 1954; Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), absent additional lateral folds (vs. present: Taylor, 1920; Inger, 1954; Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), males being smaller&mdash;known adult male 37.4 mm SVL (vs. SVL 60.4&minus;69.0 mm: Taylor, 1920; Inger, 1954), and toe webbing absent (vs. rather developed web on third, fourth, and fifth toes: Diesmos &lt;i&gt;et al.,&lt;/i&gt; 2015). &lt;i&gt;Megophrys acehensis&lt;/i&gt; &lt;b&gt;sp. nov.&lt;/b&gt; differs from &lt;i&gt;M. edwardinae&lt;/i&gt; 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 slightly shorter thighs&mdash;TL 40.4&minus;41.8% SVLh (vs. TL 45.0&minus;50.0% SVL: Inger 1989). &lt;i&gt;Megophrys acehensis&lt;/i&gt; &lt;b&gt;sp. nov.&lt;/b&gt; can be distinguished from &lt;i&gt;M. baluensis&lt;/i&gt; by having type I dorsolateral folds (vs. type III: Munir &lt;i&gt;et al.,&lt;/i&gt; 2018), males being slightly smaller&mdash;known adult male 37.4 mm SVL (vs. SVL 41.0&minus;45.0 mm: Inger &lt;i&gt;et al.,&lt;/i&gt; 1995), a rostral appendage present (vs. absent: Boulenger, 1899; Inger, 1966; Inger &lt;i&gt;et al.,&lt;/i&gt; 1995), having a triangular palpebral projection (vs. small like tubercle: Inger, 1989; Inger &lt;i&gt;et al.,&lt;/i&gt; 1995), having smaller and fewer tubercles on body flanks (vs. larger and numerous: Inger &lt;i&gt;et al.,&lt;/i&gt; 2017), and adpressed tibiotarsal articulation reaching posterior of eye (vs. shoulder: Boulenger, 1899).&lt;/p&gt; &lt;p&gt; &lt;i&gt;Megophrys acehensis&lt;/i&gt; &lt;b&gt;sp. nov.&lt;/b&gt; can be distinguished from &lt;i&gt;M. dringi&lt;/i&gt;, &lt;i&gt;M. aceras&lt;/i&gt; and &lt;i&gt;M. longipes&lt;/i&gt; by the absence of Y, X,&gt;&ndash;&lt;or H shaped folds on dorsal (vs. presence: Boulenger, 1885, 1903; Inger &lt;i&gt;et al.,&lt;/i&gt; 1995, see Table 3). Furthermore, from &lt;i&gt;M. dringi,&lt;/i&gt; the new species being smaller in male&mdash;known adult male 37.4 mm SVL (vs. SVL 43.0&minus;47.0 mm: Inger &lt;i&gt;et al.,&lt;/i&gt; 1995), having a stocky body (vs. slender: Inger &lt;i&gt;et al.,&lt;/i&gt; 1995), a rostral appendage present (vs. absent: Inger &lt;i&gt;et al.,&lt;/i&gt; 1995), having a triangular palpebral projection (vs. small like tubercle: Inger &lt;i&gt;et al.,&lt;/i&gt; 1995), vomerine teeth present (vs. absent: Inger &lt;i&gt;et al.,&lt;/i&gt; 1995), distinct tympanum (vs. partially obscured: Inger &lt;i&gt;et al.,&lt;/i&gt; 1995). From &lt;i&gt;M. aceras,&lt;/i&gt; the new species differs by having smaller body size in male&mdash;known adult male 37.4 mm SVL (vs. SVL 48.0&minus; 62.4 mm: Inger and Iskandar, 2005), a stocky body (vs. slender: Boulenger, 1903), 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), toes web absent (vs. rather developed web on third, fourth, and fifth toes: Taylor, 1962, see figure 5 in Munir &lt;i&gt;et al.,&lt;/i&gt; 2018). From &lt;i&gt;M. longipes,&lt;/i&gt; the new species differs by having a smaller body size in male&mdash;known adult male 37.4 mm SVL (vs. SVL 38.9&minus;45.2 mm: Inger and Iskandar, 2005), 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&mdash;TL 0.41&minus;0.42 SVL (vs. TL 0.55&minus;0.60 SVL: Inger and Iskandar, 2005) and tibiotarsal articulation reaching posterior corner of eye (vs. far beyond tip of snout; Boulenger 1885).&lt;/p&gt; &lt;p&gt; &lt;b&gt;Distribution and Natural History.&lt;/b&gt; The holotype of &lt;i&gt;Megophrys acehensis&lt;/i&gt; &lt;b&gt;sp. nov.&lt;/b&gt; was collected on leaf litter in a sloping area at the edge of a primary forest near a stream, while the paratype was collected from leaf litter in a palm oil plantation near the edge of an old secondary forest. Landslides, new road development, and monoculture forests have become major threats at the holotype locality, while the threats at the paratype locality were the land use changes and water pollution from palm oil fields. The precise distribution, population, habitat requirements, breeding behavior, call and tadpole information are unknown. The following anuran species have been found sympatrically with the new species, at holotype locality: &lt;i&gt;Limnonectes&lt;/i&gt; sp; &lt;i&gt;Philautus larutensis&lt;/i&gt;; &lt;i&gt;Sumaterana dabulescens&lt;/i&gt; Arifin, Smart, Hertwig, Smith, Iskandar, and Hass; at the paratype locality: &lt;i&gt;Chalcorana chalconota&lt;/i&gt;; &lt;i&gt;Leptophryne borbonica&lt;/i&gt;; &lt;i&gt;Limnonectes kuhlii&lt;/i&gt;; &lt;i&gt;L. macrodon&lt;/i&gt;; &lt;i&gt;Limnonectes&lt;/i&gt; sp.; &lt;i&gt;Rhacophorus catamitus&lt;/i&gt;; &lt;i&gt;Philautus&lt;/i&gt; sp. and &lt;i&gt;Pulchrana fantastica&lt;/i&gt; Arifin, Cahyadi, Smart, Jankowski, and Haas.&lt;/p&gt;Published as part of &lt;i&gt;Munir, Misbahul, Nishikawa, Kanto, Hamidy, Amir &amp; Smith, Eric N., 2021, Two new species of Megophrys Kuhl and Van Hasselt (Amphibia: Megophryidae) from Sumatra, Indonesia, pp. 503-529 in Zootaxa 5057 (4)&lt;/i&gt; on pages 514-520, DOI: 10.11646/zootaxa.5057.4.3, &lt;a href="http://zenodo.org/record/5598859"&gt;http://zenodo.org/record/5598859&lt;/a&gt