Robert F. Inger

High level of cryptic species diversity revealed by sympatric lineages of Southeast Asian forest frogs

Amphibians tend to exhibit conservative morphological evolution, and the application of molecular and bioacoustic tools in systematic studies have been effective at revealing morphologically ‘cryptic’ species within taxa that were previously considered to be a single species. We report molecular genetic findings on two forest-dwelling ranid frogs from localities across Southeast Asia, and show that sympatric evolutionary lineages of morphologically cryptic frogs are a common pattern. These findings imply that species diversity of Southeast Asian frogs remains significantly underestimated, and taken in concert with other molecular investigations, suggest there may not be any geographically widespread, forest-dwelling frog species in the region. Accurate assessments of diversity and distributions are needed to mitigate extinctions of evolutionary lineages in these threatened vertebrates.

The Life of the Rainbow Lizard

The life of the rainbow lizard , The life of the rainbow lizard , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی

A photographic guide to snakes and other reptiles of peninsular Malaysia, Singapore and Thailand

A compact companion to snakes and reptiles encountered in peninsular Malaysia, Singapore and Thailand. Over 220 species are covered and each description is accompanied by a photograph. Venomous snakes are identified. The introduction contains information on their biology, habitat and behaviour.

Availability of new Bayesian-delimited gecko names and the importance of character-based species descriptions

Leache & Fujita [[1][1]] present an empirical example of Bayesian species delimitation (BSD; [[2][2]]) to recognize three new species of African geckos from within the range of the widespread taxon Hemidactylus fasciatus , Gray 1842. As with any new method, BSD will undoubtedly generate questions

Impending conservation crisis for Southeast Asian amphibians

With an understudied amphibian fauna, the highest deforestation rate on the planet and high harvesting pressures, Southeast Asian amphibians are facing a conservation crisis. Owing to the overriding threat of habitat loss, the most critical conservation action required is the identification and strict protection of habitat assessed as having high amphibian species diversity and/or representing distinctive regional amphibian faunas. Long-term population monitoring, enhanced survey efforts, collection of basic biological and ecological information, continued taxonomic research and evaluation of the impact of commercial trade for food, medicine and pets are also needed. Strong involvement of regional stakeholders, students and professionals is essential to accomplish these actions.

Organization of a community of tadpoles in rain forest streams in Borneo

Samples of 29 distinct larval forms of anurans were collected in streams flowing through primary rain forest at Nanga Tekalit, Sarawak, at three periods spaced over 22 years. This assemblage of tadpoles lives in torrents, riffles, shingle areas, open pools, leaf drifts, protected side pools, potholes in rocky banks, bank seepages, and pools of small intermittent streams. Positive associations of species in types of microhabitats and co-occurrence within sites lead to recognition of four taxonomically heterogeneous groups: one concentrated in leaf drifts; one using riffles, shingle areas, and open pools; one concentrated in potholes; and one using side pools and potholes. Most pairs of larval forms having strong negative association are characterized by differences in morphology and feeding behaviour; they show little evidence of competitive relations. Between-sites variation in species composition differs among the types of microhabitats, leaf drifts showing the least amount of variation. Species composition within a site shows less change over intervals of 1-5 days than over intervals of 13-18 days. Variation in species composition is greater between sites than within sites over intervals of 9-31 days. Organization in this community seems to be effected by three factors: reproductive behaviour of adults and morphological and behavioural adaptations of tadpoles.

Adaptations for Life in Tree Holes by Rhacophorid Tadpoles from Thailand

Larvae of two species of rhacophorids are reported from tree holes in Thailand. One, referred to Theloderma stellatum, has a body nearly as wide as long and a denticle formula of 1:3+3/1+1:11. Internally, it has large branchial baskets with many rows of dense gill filters, but only two filter cavities. It has secretory cells in its branchial food traps, but they are not arranged in ridges. Its buccal musculature is slight. The larva of the second species, referred to Philautus (cf. carinensis) has a truncated snout, anteriorly directed mouth, denticle formula I/O, and unusually shaped beaks with the upper portion concave but serrations confined to the lower. It has huge buccal musculature. In this form all branchial structures associated with suspension feeding, and respiratory gill filaments, are absent. Both larvae have large, anteriorly placed glotta, which are evidently adaptations for aerial respiration. The Theloderma has a peculiar mosaic of feeding structures associated with dietary extremes of microphagy and macrophagy. Its gut contents consist of both large and small food items. The Philautus larva has features of an obligate macrophagous larva. From its gut contents it appears to eat only frog eggs. Certain arboreal tadpoles for the New World tropics, e.g., Hyla zetecki and others, resemble these Philautus tadpoles in form and diet. No analog of larval Theloderma stellatum is yet known from the American tropics.

A comparison of amphibian communities through time and from place to place in Bornean forests

We sampled riparian frogs along 18 streams at eight localities in Borneo. At four of these sites we sampled during more than one year. Altogether 49 species were included in our study and total sample size was 13,249. We measured overlap in species occurrences and arrays of abundances within and among localities. Variation over the time span of our study was minor within communities. Overlaps between streams at a locality were generally higher than overlaps of pairs of streams from different localities. Environmental variation, particularly in stream width and gradient, had a clear effect on both intra-and inter-locality overlaps. Although rainfall varied between localities and within localities over time, that variation did not seem to affect overlaps among or within communities. Environmental factors did not account for all differences in overlaps between communities. Instead, regional processes, perhaps the timing of barriers or speciation events, appear to have been responsible for geographic restrictions of several species, leading to variation in overlap values.

Ecological structure of a herpetological assemblage in South India

We collected detailed microhabitat information on 1460 specimens comprising 52 species of amphibians and reptiles from a small area of tropical evergreen forest in South India. Although most individuals were found in non-riparian situations, the number caught in and along streams was higher than expected on the basis of collecting effort. Very few animals were caught under logs and rocks. When niche breadth values are corrected for variation in sample size, we find no correlation between magnitude of niche breadth and general habitat usage, such as terrestriality vs. arboreality. A cluster analysis of 28 common species using niche overlap values reveals one group of 6 terrestrial species with very high niche overlap values and high co-occurrence within collecting sorties; this group probably represents a genuine terrestrial guild. Another set of 4 terrestrial species is peripherally associated with the first 6, whereas the remaining species show generally low overlap values. Altitudinal restriction is an almost ubiquitous feature of the distribution of species in this fauna, with distinct groups of low (below 300 m), intermediate (300-399 m), and high altitude (above 399 m) taxa roughly corresponding to major shifts in forest types. At a broader level of analysis, we find considerable evidence for local endemism within partially isolated hill ranges in the Western Ghats, suggesting that geographic isolation may be an important contributing factor to the diversity of the South Indian herpetofauna.

Annual Reproduction and Clutch Size in Rain Forest Frogs from Sarawak

Six Bornean species of rain forest frogs-Bufo asper, Rana blythi, R. ibanorum, R. macrodon, R. hosei, and Amolops jerboa-apparently breed throughout the year. There was no evidence of seasonal trends in spermatocyte counts, egg size, or proportion of ripe females, in spite of variations from month to month. The clutch sizes of the four species of Rana are smaller than those of temperate zone species of comparable size, whereas B. asper does not differ from related temperate species in this regard. Comparison of A. jerboa with temperate species in terms of egg counts is uncertain.