Hoi Sen Yong

Systematic relationships of Oriental tiny frogs of the family Microhylidae (Amphibia, Anura) as revealed by mtDNA genealogy

We estimated the genealogical relationships and assessed systematic relationships among 45 out of 89 named species and four unnamed taxa from 11 of 14 genera of the Oriental microhylids from 1767 bp sequences of the mitochondrial DNA genes 12S rRNA and 16S rRNA using maximum parsimony, maximum likelihood, and Bayesian inference methods. Monophyly was rejected for the subfamily Microhylinae, and our data reveal four well-supported clades whose relationships to each other are unresolved: (A) Microhyla, Calluella, and Glyphoglossus, (B) Chaperina, (C) Kaloula, Phrynella, and Metaphrynella, and (D) Micryletta. They were genetically as divergent from each other as from another Oriental subfamily Kalophryninae, and could be recognized as distinct subfamilies. Within Clade A, our data reveal three well-supported subclades whose relationships to each other are unresolved: (AI) Microhyla-I, (AII) Calluella and Glyphoglossus, and (AIII) Microhyla-II. Of the two enigmatic Malaysian genera, whose subfamilial placement has been undetermined, Phrynella was found to be the sister species of Metaphrynella in Clade C, whereas Gastrophrynoides was grouped in the Papua-Australian subfamily Asterophryinae. Currently recognized subgenera and species groups within Microhyla based on morphology were not supported phylogenetically, and require thorough reassessments.

Phylogenetic and taxonomic relationships of the Polypedates leucomystax complex (Amphibia)

Kuraishi, N., Matsui, M., Hamidy, A., Belabut, D. M., Ahmad, N., Panha, S., Sudin, A., Yong, H. S., Jiang, J.‐P., Ota, H., Thong, H. T. & Nishikawa, K. (2012). Phylogenetic and taxonomic relationships of the Polypedates leucomystax complex (Amphibia). —Zoologica Scripta, 42, 54–70.

From Antarctica or Asia? New colonization scenario for Australian-New Guinean narrow mouth toads suggested from the findings on a mysterious genus Gastrophrynoides

BackgroundMicrohylidae is a geographically widespread family of anurans. Although several extensive molecular analyses have attempted to elucidate their subfamilial relationships, and correlate these with Mesozoic and Cenozoic continental drifts, consensus has not been reached. Further, generic level relationships have not been well investigated in some microhylid subfamilies, and therefore subfamilial affiliations of some genera are still unclear. To elucidate the phylogenetic positions of two mysterious Asian genera, Gastrophrynoides and Phrynella, and to better understand the trans-continental distributions of microhylid taxa, we performed molecular phylogenetic and dating analyses using the largest molecular dataset applied to these taxa to date.ResultsSix nuclear and two mitochondrial genes (approx. 8 kbp) were sequenced from 22 microhylid frog species representing eight subfamilies. The maximum likelihood and Bayesian analyses could not fully elucidate the subfamilial relationships, suggesting a rapid radiation of these taxa between 85 and 66 million years ago. In contrast, generic relationships of Asian microhylines were generally well resolved.ConclusionOur results clearly showed that one of two problematic Asian genera, Phrynella, was nested in the clade of the Asian subfamily Microhylinae. By contrast, Gastrophrynoides occupied the most basal position of the Australian-New Guinean subfamily Asterophryinae. The estimated divergence of Gastrophrynoides from other asterophryine was unexpectedly around 48 million years ago. Although a colonization scenario via Antarctica to the Australian-New Guinean landmass has been suggested for Asterophryinae, our finding suggested a novel colonization route via Indo-Eurasia.

A New Species of Leptolalax (Amphibia, Anura, Megophryidae) from Peninsular Malaysia

A new megophryid species, Leptolalax kecil, is described from the Cameron Highlands of Peninsular Malaysia on the basis of acoustic and morphological characteristics. It has an advertisement call dissimilar to that of other, congeneric species, and is the smallest of the known Leptolalax. It is similar to L. pluvialis from Vietnam in small body size, but differs from it in ventral color, and in the size and color of the pectoral gland. The distributional pattern of the new species is discussed.

Molecular phylogeny and biogeography of caecilians from Southeast Asia (Amphibia, Gymnophiona, Ichthyophiidae), with special reference to high cryptic species diversity in Sundaland

We investigated the phylogenetic relationships and estimated the history of species diversification and character evolution in two ichthyophiid genera: Caudacaecilia and Ichthyophis. We estimated the phylogenetic relationships of 67 samples from 33 localities in Southeast Asia from 3840-bp sequences of the mitochondrial 12S rRNA, 16S rRNA, and cyt b genes using Bayesian inference, maximum likelihood, and maximum parsimony methods. The Southeast Asian samples formed a well-supported clade differentiated from a South Asian sample. The Southeast Asian clade was divided into two subclades, one containing samples from South China, Indochina, Malay Peninsula, and Java. The other consisted of samples from Borneo and the Philippines. Neither Caudacaecilia nor Ichthyophis was monophyletic, nor did samples with or without light stripes lateral to the body form clades. We found several distinct sympatric lineages and undescribed species, especially from Sundaland.

Genetic Divergence and Evolutionary Relationship in Fejervarya cancrivora from Indonesia and Other Asian Countries Inferred from Allozyme and MtDNA Sequence Analyses

To elucidate genetic divergence and evolutionary relationship in Fejervarya cancrivora from Indonesia and other Asian countries, allozyme and molecular analyses were carried out using 131 frogs collected from 24 populations in Indonesia, Thailand, Bangladesh, Malaysia, and the Philippines. In the allozymic survey, seventeen enzymatic loci were examined for 92 frogs from eight representative localities. The results showed that F. cancrivora is subdivided into two main groups, the mangrove type and the large- plus Pelabuhan ratu types. The average Nels genetic distance between the two groups was 0.535. Molecular phylogenetic trees based on nucleotide sequences of the 16S rRNA and Cyt b genes and constructed with the ML, MP, NJ, and BI methods also showed that the individuals of F. cancrivora analyzed comprised two clades, the mangrove type and the large plus Pelabuhan ratu / Sulawesi types, the latter further split into two subclades, the large type and the Pelabuhan ratu / Sulawesi type. The geographical distribution of individuals of the three F. cancrivora types was examined. Ten Individuals from Bangladesh, Thailand, and the Philippines represented the mangrove type; 34 Individuals from Malaysia and Indonesia represented the large type; and 11 individuals from Indonesia represented the Pelabuhan ratu / Sulawesi type. Average sequence divergences among the three types were 5.78–10.22% for the 16S and 12.88–16.38% for Cyt b. Our results suggest that each of the three types can be regarded as a distinct species.

Acoustic characteristics and systematic relationships of arboreal Microhylid frogs of the genus Metaphrynella from Malaysia

Metaphrynella Parker, 1934 is a genus of two species in the subfamily Microhylinae, family Microhylidae (Frost, 1985) found in rainforests in southeast Asia. Metaphrynella pollicaris (Boulenger, 1890) is confined to the Malay Peninsula and Sumatra, whereas M. sundana (Peters, 1867) occurs only in Borneo (Inger, 1966). The taxonomic relationship of these two species has not been studied adequately, and the phylogenetic relationships of this genus are not clear. Metaphrynella pollicaris has long been noted for its habit of calling from tree holes (Flower, 1896). Previous descriptions of its calls are anecdotal (e.g., Grandison, 1972), and a sonagram provided by Dring (1979) lacked a detailed description. Similarly, only verbal descriptions are available for the Bornean M. sundana (Inger and Stuebing, 1989). On the other hand, acoustic characteristics of some microhylines have been well studied, and their evolutionary significance in some species has been discussed by Blair (1955) and Loftus-Hills and Littlejohn (1992). The genera hitherto analyzed, however, are mostly confined to the New World ones (Blair, 1955; Nelson, 1973), and only a few genera from the old World have been studied (Heyer, 1971; Nelson, 1973; Kuramoto, 1987). The acoustic data are thus still insufficient for outlining the phylogenetic relationships of the genera in this subfamily. In order to understand better the systematic relationship of Metaphrynella pollicaris and M. sundana, as well as their position in the Microhylinae, we analyzed their acoustic characteristics and herein discuss phylogenetic problems. Recordings of calls were made in the field using a cassette tape recorder (Sony TC-D5) with an external microphone (Sony ECM-23F). Ambient temperature was measured at the time of recording. Calls of M. pollicaris were recorded in peninsular Malaysia, first at Frasers Hill (altitude 1200 m) on 11 December 1991, both in the field and in a room after they are captured. Air temperatures at the time of recording were 19.3 C and 18.7 C, respectively. Additional recordings at 23.7 C were made on 15 January 1992 on Genting Highland (altitude 900 m). Calls of M. sundana were recorded at the Headquarters of the Mulu National Park (altitude 50 m), on 27 and 29 July 1993 at air temperatures of 24.9 and 23.7 C, respectively. All voucher specimens are temporarily stored at the Graduate School of Human and Environmental Studies, Kyoto University (KUHE) and will be deposited at the University of Malaya and the Forset Department, Sarawak. The recorded calls were analyzed using computer programs, SoundEdit Vers. 2 or SoundEdit Pro (MacroMind-Paracomp, Inc.) by a Macintosh computer. In the following description, note gap means the time from the beginning of one note to the beginning of the next note. Mann-Whitney U tests were performed to detect the presence or absence of differences in the frequency distributions. The significance level was set at 0.05.