The island of Mindanao in the southern Philippines has the richest herpetofauna presently documented for any one island in the archipelago, although many regions on the island are yet to be explored. Limestone karst habitats, in particular, are poorly surveyed and are also the most threatened ecosystems in the Philippines. We conducted field surveys on the herpetofauna of Mount Capistrano, a low-elevation limestone karst habitat and an ecotourism destination in the central Mindanao Province of Bukidnon. Our study is the first biodiversity assessment of the area. We recorded a total of 32 species consisting of 10 frogs, nine lizards, and 13 snakes. Nine are Philippine endemic species, whereas seven are found only in the Mindanao faunal region. Three are invasive alien species. We also provide preliminary information on a putative new species of limestone frog of the genus Platymantis. Our study shows that despite disturbance, limestone karst forests in Mindanao harbor significant levels of herpetofaunal species richness, including undiscovered micro-endemics. This study reinforces the biological significance of karst habitats and the critical need to conduct comprehensive biodiversity inventories of this unique, naturally patchily distributed, and highly threatened ecosystem throughout the Philippines.

Tropical watershed ecosystems support heterogeneous habitats and diverse non-human species assemblages, together providing ecosystem services to humans. Amphibians and reptiles are recognized as sensitive indicators of ecosystem “health,” related to beneficial services (provisional, regulating, cultural, structural, functional) human societies receive from terrestrial watersheds. The Taguibo Watershed supplies fresh drinking water to Butuan City in the Caraga Region of northeast Mindanao Island. However, very little is known about the herpetofauna of the area. Here, we synthesize biodiversity data from historical (1971, 1979) and recent (2013, 2017) herpetological surveys from the region. We utilize specimen-associated occurrence records and natural history information to produce a species inventory, analyze their habitat utilization, and characterize diversity metrics to describe herpetological communities of the watershed – resulting in 44 species (27 new records). A number of historically-documented species persist, having partitioned riparian and terrestrial habitat types in dipterocarp and secondary-growth forests of Taguibo. Reptiles exhibit little overlap in the use of microhabitats – in contrast to amphibians, which exhibit either unique or frequently shared microhabitat substrates. In terrestrial microhabitats (not immediately associated with water), many newly-recorded reptiles and amphibians (particularly, of the genus Platymantis) partition space predictably – either occupying a single microhabitat or, in one species (a pit viper, Tropidolaemus subannulatus), two microhabitats. We anticipate that our initial characterization of Taguibo’s herpetofauna may serve as a baseline to promote further research and facilitate conservation initiatives. We emphasize the importance of primary sources – field-based surveys and re-surveys – and open-access biodiversity data served via online platforms that provide live, transparent access to original, unaltered data. Anthropogenic threats involving economic-driven activities present a need for field-based research in support of watershed management. Periodic, survey, and re-survey studies – continuously updating earlier work – are the most reliable, repeatable, and publicly-transparent use of biodiversity survey data in support of societal benefits and ecosystem services.

One significant challenge to biodiversity assessment and conservation is persistent gaps in species diversity knowledge in Earth’s most biodiverse areas. Monitoring devices that utilize species-specific advertisement calls show promise in overcoming challenges associated with lagging frog species discovery rates. However, these devices generate data at paces faster than it can be analyzed. As such, automated platforms capable of efficient data processing and accurate species-level identification are at a premium. In addressing this gap, we used TensorFlow Inception v3 to design a robust, automated species identification system for 41 Philippine frog species (genus Platymantis), utilizing single-note audio spectrograms. With this model, we explored two concepts: (1) performance of our deep-learning model in discriminating closely-related frog species based on images representing advertisement call notes, and (2) the potential of this platform to accelerate new species discovery. TensorFlow identified species with a ~ 94% overall correct identification rate. Incorporating distributional data increased the overall identification rate to ~ 99%. In applying TensorFlow to a dataset that included undescribed species in addition to known species, our model was able to differentiate undescribed species through variation in “certainty” rate; the overall certainty rate for undescribed species was 65.5% versus 83.6% for described species. This indicates that, in addition to discriminating recognized frog species, our model has the potential to flag possible new species. As such, this work represents a proof-of-concept for automated, accelerated detection of novel species using acoustic mate-recognition signals, that can be applied to other groups characterized by vibrational cues, seismic signals, and vibrational mate-recognition.

We describe a new species of frog of the genus Platymantis Günther (subgenus Tirahanulap), from the east-central regions of the Philippines. It belongs to the the previously-defined P. hazelae Group) based on morphological and bioacoustic datasets. The new species is phenotypically and ecologically most similar to members of Tirahanulap, an assemblage of small-bodied arboreal frogs inhabiting montane forests of the central and northern islands of the Philippine archipelago. The new species represents the first taxon in the Cloud Frog species known from the biogeographically unique Mindanao Pleistocene Aggregate Island Complex. Particularly susceptible to local extirpation following deforestation, all known species of Tirahanulap are important indicator species for environmental and conservation assessments, making this new species not only an exceptional addition to Philippine biodiversity but also an important symbol for conservation initiatives in the region.

We describe a new species of limestone karst dwelling forest frog of the genus Platymantis from the Quezon Protected Landscape in southeastern Luzon Island, Philippines. We assign Platymantis quezoni, sp. nov., to the diverse assemblage of terrestrial species in the Platymantis dorsalis Group, subgenus Lupacolus on the basis of its body size and proportions, only slightly expanded terminal discs of the fingers and toes, and its terrestrial microhabitat. The new species is distinguished from these and all other Philippine congeners by features of its external morphology, its restriction to a distinctive limestone karst microhabitat, and its advertisement call, which is unique among frogs of the family Ceratobatrachidae. Several distinguishing morphological characters include its moderate body size (22.1-33.9 mm SVL for 16 adult males and 32.4-39.7 mm SVL for five adult females), slightly expanded terminal discs of the fingers and toes, smooth skin with limited dermal tuberculation, and a dorsal color pattern of mottled tan to dark brown with black blotches. The new species is the sixth Philippine Platymantis known to occur exclusively on limestone karst substrates (previously known karst-obligate species include: P. bayani, P. biak, P. insulatus, P. paengi, and P. speleaus). Recently accelerated discovery of limestone karst anurans across the Philippines suggests that numerous additional species may await discovery on the hundreds of scattered karst formations throughout the archipelago. This possibility suggests that a major conservation priority in coming years will be to study, characterize, describe, and preserve the endemic species supported by this patchy, unique and imperiled type of forest ecosystem in the Philippines.

Two new taxa of the ceratobatrachid genus Platymantis are described from western New Guinea on the basis of bioacoustic, morphological, ecological and biochemical studies. One of these, described as new species, is known only from in the Fakfak Mountains (Bomberai Peninsula) and the other, described as new subspecies, from Yapen Island. Their nearest relatives appear to be P. batantae Zweifel, 1969, and P. cryptotis Günther, 1999 respectively. Besides data on the new taxa, some morphological, bioacoustic and molecular data are given for P. papuensis Meyer, 1875 from the type locality Biak Island.

Multilocus phylogeny and a new classification for Southeast Asian and Melanesian forest frogs (family Ceratobatrachidae)

We describe a new-species of high elevation rainforest shrub frog (genus Platymantis) from the Nakanai Mountains of eastern New Britain (Bismarck Archipelago), Papua New Guinea. The distinctive new species possesses a moderate body size (29.5-32.2 mm in four males), widely expanded finger and toe disks, smooth to slightly granular dorsal skin, low but distinctly protuberant supraocular and tarsal tubercles, a conspicuous series of bright yellow flank areolations, a low but distinct intraocular sagittal crest, bronze-brown iris, and a unique advertisement call. We compare the new species with congeneric New Britain taxa and to other phenotypically similar species from the Solomon-Bismarck-Admiralty archipelagos. The new species is phenotypically most similar to P macrosceles Zweifel 1975, and has been collected at only one high elevation site (Tompoi Camp). The available data suggest that the new species, known from 1700 m, is elevationally segregated from P. macroscles (to date, only recorded from 800-900 m in the Nakanai Mountains). New Britain Island has emerged as a major center of endemic ceratobatrachid species diversity. Additional species are anticipated to result from ongoing field work, especially in the western portion of the island, which remains largely unexplored.

This study described the advertisement calls of two ground-dwelling species of frogs of the genusPlatymantis from Mount Magdiwata, San Francisco, Agusan del Sur, Philippines. The two species shared a common micro-habitat preference being found on rocks or edges of slope ground, leaf litter, and on steep slopes of stream banks. The researchers analyzed the calls for their temporal and spectral characteristics. Audiospectrograms, oscillograms and power spectra presented the numerical parameters and graphical representations of the advertisement calls. The vocalization of both species revealed significant differences in terms of the dominant frequency, call duration, number of notes, note duration, and intercall at p < 0.01. Statistical analysis of Platymantis magdiwataspecies A showed a positive correlation between the body size length and note duration (R2 = 0.377, p<0.01). On the other hand, the body size length of Platymantis magdiwata species B showed a negative correlation with the dominant frequency (R2 = -0.248; p<0.01), and a positive correlation with the call duration and the number of notes (R2 = 0.698 and R2 = 0.699; p<0.01). Both species possess unique advertisement calls that distinguish them from each other. Key words: Bioacoustics, advertisement call, Platymantis, Philippines.

Direct embryonic development belongs to one of six unique developmental guilds within the endotrophic anurans. Few studies have been conducted on the embryonic development of direct developers. Herein, we present a unique form of embryonic development for direct developers from the genus Platymantis (Family Ceratobtrachidae). We incubated fertile eggs (n=2 egg clutches; 40 eggs per clutch) of the endangered Fijian ground frog Platymantis vitiana under controlled laboratory conditions (25 °C and 100% relative humidity). Embryonic development (fertilization to hatching) took on average 29 days. Several unique embryonic structures were recorded, including the presence of very large eggs [8.5 mm diameter inclusive of egg-jelly and yolk, with the largest yolk diameter (6.0 mm) recorded for the genus Platymantis], the complete loss of the usual larval mouthparts, egg-tooth, gill buds and gills. Embryonic structural specialization included large abdominal sacs with blood capillaries which are likely the main medium of gas and waste exchange in P. vitiana. We provide a novel 10-stage staging system of embryonic development for P. vitiana which may also be useful for staging other members of the Platymantis genus. Our study contributes to existing knowledge on the developmental biology of the little studied direct developing endotrophic anurans.

We describe a new species of terrestrial limestone forest frog of the genus Platymantis from Biak Na Bato National Park in central Luzon Island, Philippines. Platymantis biak is assigned to the primarily arboreal Platymantis guentheri Species Group, and is distinguished from these and other congeners by features of its external morphology and preferred terrestrial limestone microhabitat. Several distinguishing morphological characters include a moderately large body (32.3–39.9 mm SVL for 23 males and 37.4–42.4 mm SVL for 8 females), moderately expanded finger discs and slightly expanded toe discs, smooth skin, and limb banding pattern. The new species is yet another species in a rapidly growing group of newly discovered Philippine forest frogs with preferences for forested, karst habitats.

Abstract A new species of forest frog of the genus Platymantis is described from an elevation of 140 m in the Taft Forest Reserve in eastern Samar Island, Philippines. It is assigned to the Platymantis guentheri Species Group, a group of primarily arboreal species, and is distinguished from these and other congeners by features of its external morphology and its preferred terrestrial, limestone microhabitat. Several striking morphological characters include a large body (34.2–39.1 mm SVL for 9 males and 44.3–49.8 mm SVL for 9 females), greatly expanded finger and toe discs, large eyes, spotted flanks, and sparsely-distributed, salmon-colored dorsal dermal tubercles. The new species represents the second largest Philippine Platymantis, the third terrestrial species in the P. guentheri Group, and the only known species of Platymantis from the Mindanao Faunal Region with a preference for forested, karst habitats.

We describe two new species of forest frogs in the genus Platymantis from the Isabel Island group, Solomon Islands. One new species is a medium-sized, terrestrial form that is morphologically most similar to P. weberi (a widespread Solomon Islands species). The other new species is an arboreal frog that is morphologically similar to Platymantis neckeri (known from Bougainville, Choiseul, and Isabel islands). Both new species possess unique advertisement calls that distinguish them from all sympatric congeners. Because acoustic characteristics function as the primary mate-recognition signals for anuran species, and are therefore an excellent indicator of the status of unique evolutionary lineages, we recognize each as new species. We diagnose both new species on the basis of their distinctive advertisement calls and in the case of the terrestrial form, by differences in body size, body proportions and skin texture. The diversity of ceratobatrachid frogs of the Solomon islands and Bougainville is underestimated and in need of a comprehensive taxonomic review coupled with a standardized survey of acoustic characters.

On the basis of museum collections and field work, new discoveries were made concerning the morphology, distribution, bioacoustics and ecology of the hitherto New Guinean species Platymantis papuensis, P. punctata and P. batantae. Moreover, two species, Platymantis cryptotis and Platymantis bimaculata, are described as new. Eventual evolutionary relationships among Papuan Platymantis species are discussed. It is supposed that P. punctata is the most primitive of the Platymantis species from New Guinea and adjacent islands. Species pairs with derived characters are P. batantae and P. bimaculata as well as P. papuensis and P. cryptotis.

Two new species of the ceratobatrachid frog genus Platymantis are described from the Admiralty Archipelago, Papua New Guinea. Platymantis admiraltiensis sp. nov. and P. latro sp. nov. have been confused with P. gilliardi Zweifel, 1960 which is known with certainty only from New Britain in the Bismarck Archipelago. Platymantis admiraltiensis sp. nov. differs from P. gilliardi in its much longer legs (TL/SV 0.54–0.60 vs 0.51 in the holotype of P. gilliardi), and from all species of the morphologically conservative P. papuensis complex by its advertisement call, a long series of slowly-repeated (~ 0.4–1.9/s) yapping notes lasting up to 44 seconds. Platymantis latro sp. nov. differs from P. gilliardi and all other members of the P. papuensis complex in having a broad dark stripe laterally on the head and an advertisement call consisting of a single biphasic note with 10–20 short, irregularly spaced pulses followed by one long, musical pulse. Both new species are known only from the Admiralty Archipelago. This study confirms the utility of advertisement call structure for distinguishing among morphologically similar ceratobatrachid taxa.

We describe a new species of forest frog (genus Platymantis) from 180-300 m above sea level on Mt. Lihidan in the northwestern part of Panay Island, Philippines. It is assigned to the Platymantis dorsalis species group and is distinguished from congeners by external morphology, various spectral and temporal components of the advertisement call, and a preference for terrestrial, limestone microhabitat. Unique morphological characters include a moderately large body (27.7-34.3 mm SVL for 15 males), slightly expanded terminal finger and toe discs, distinctly rugose dorsal and lateral skin, pronounced supratympanic fold, protuberant rictal tubercle cluster, hidden dorsal and posterior edges of tympanum, and unique coloration.

Abstract We describe a new species of forest frog (genus Platymantis) from Mt. Malinao, Bicol Peninsula, southern Luzon Island, The Philippines. The new species is distinguished from congeners by a moderate body size (28.3–39.1 mm for eight males; 49.8–52.7 in two females), slightly expanded terminal finger and toe disks, a distinct color pattern, a unique microhabitat preference, and various spectral and temporal aspects of the advertisement call. The new species is known only from 950–1160 m above sea level on Mt. Malinao and, as such, accentuates this mountain's unrecognized conservation significance as a minor center of herpetological diversity and endemism on southern Luzon. We compare the new species to all presumably related (phenotypically similar) species of Platymantis from the Philippines and comment on apparent trends in morphological evolution and habitat preference in Philippine members of the genus Platymantis. Current understanding of Platymantis species diversity throughout this topograph...

Brown, Rafe M., Richards, Stephen J., Sukumaran, Jeet, Foufopoulos, Johannes (2006): A new morphologically cryptic species of forest frog (genus Platymantis) from New Britain Island, Bismarck Archipelago. Zootaxa 1334: 45-68, DOI: 10.5281/zenodo.174282

We describe a new species of high-elevation rainforest tree frog (genus Platymantis) from the Nakanai Mountains, New Britain Island, Bismarck Archipelago, Southwestern Pacific. The new species is characterized by moderate body size (34.2–35.8 mm for four males), widely expanded terminal digital disks of the fingers and toes, smooth skin of the dorsum, a distinctive color pattern, and a complex, amplitude-modulated advertisement call produced in groups of 3–6 notes. We compare the new species to all known species of Platymantis from New Britain and to additional phenotypically similar species from the Solomon Islands and Fiji. It is most similar to P. nexipus, a species known previously from only a single specimen. We rediagnose and redescribe P. nexipus on the basis of the holotype and ten recently collected specimens, provide the first descriptions of the advertisement calls of both species, and comment on an additional suspected undescribed species from the Nakanai Mountains of New Britain Island.

We describe a new species of forest frog in the genus Platymantis from New Britain Island, Bismark Archipelago, Papua New Guinea. The new species is a morphologically cryptic form that has masqueraded for almost four decades under the name P. schmidti (formerly P. papuensis schmidti, Brown &amp; Tyler, 1968). The new species is microsympatric with the geographically widespread P. schmidti at two known localities. We diagnose the new species on the basis of its distinctive advertisement call and slight but consistent differences in body size and proportions. Calling males of the new species appear to prefer more elevated perches than do males of P. schmidti and the new species may exhibit a greater extent of sexual size dimorphism.