Djoko Iskandar

The Asian common toad (Duttaphrynus melanostictus) is a human commensal species that occupies a wide variety of habitats across tropical Southeast Asia. We test the hypothesis that genetic variation in D. melanostictus is weakly associated with geography owing to natural and human-mediated dispersal facilitated by its commensal nature. Phylogenetic and population genetic analyses of mitochondrial and nuclear DNA sequence variation, and predictive species distribution modelling, unexpectedly recovered three distinct evolutionary lineages that differ genetically and ecologically, corresponding to the Asian mainland, coastal Myanmar and the Sundaic islands. The persistence of these three divergent lineages, despite ample opportunities for recent human-mediated and geological dispersal, suggests that D. melanostictus actually consists of multiple species, each having narrower geographical ranges and ecological niches, and higher conservation value, than is currently recognized. These findings also have implications for the invasion potential of this human commensal elsewhere, such as in its recently introduced ranges on the islands of Borneo, Sulawesi, Seram and Madagascar.

EnglishSpanish; CastilianEnglishSpanish; CastilianAbstractAbstract: Little is known about the effects of anthropogenic land-use change on the amphibians and reptiles of the biodiverse tropical forests of Southeast Asia. We studied a land-use modification gradient stretching from primary forest, secondary forest, natural-shade cacao agroforest, planted-shade cacao agroforest to open areas in central Sulawesi, Indonesia. We determined species richness, abundance, turnover, and community composition in all habitat types and related these to environmental correlates, such as canopy heterogeneity and thickness of leaf litter. Amphibian species richness decreased systematically along the land-use modification gradient, but reptile richness and abundance peaked in natural-shade cacao agroforests. Species richness and abundance patterns across the disturbance gradient were best explained by canopy cover and leaf-litter thickness in amphibians and by canopy heterogeneity and cover in reptiles. Amphibians were more severely affected by forest disturbance in Sulawesi than reptiles. Heterogeneous canopy cover and thick leaf litter should be maintained in cacao plantations to facilitate the conservation value for both groups. For long-term and sustainable use of plantations, pruned shade trees should be permanently kept to allow rejuvenation of cacao and, thus, to prevent repeated forest encroachment.AbstractResumen: Se conoce poco de los efectos del cambio de uso de suelo antropogénico sobre los anfibios y reptiles en los biodiversos bosques tropicales del sureste de Asia. Estudiamos un gradiente de modificación de uso de suelo(bosque primario, bosque secundario, agrobosque de cacaco con sombra natural, agrobosque de cacao con sombra sembrada y áreas abiertas) en Sulawesis central (Indonesia). Determinamos la riqueza de especies, abundancia, recambio y composición de la comunidad en todos los tipos de hábitat y las relacionamos con variables ambientales como la heterogeneidad del dosel y grosor de la capa de hojarasca. La riqueza de especies de anfibios disminuyó sistemáticamente a lo largo del gradiente de modificación del uso de suelo, pero la riqueza y abundancia de anfibios fue mayor en los agrobosques de cacao con sombra natural. Los patrones de riqueza y abundancia de especies en el gradiente de perturbación fueron mejor explicados por la cobertura del dosel y el grosor de la hojarasca en anfibios y por la heterogeneidad y cobertura del dosel en reptiles. Los anfibios fueron afectados más severamente que los reptiles por la perturbación del bosque en Sulawesi. Para facilitar el valor de conservación para ambos grupos, se debe mantener una cobertura de dosel heterogénea y una capa gruesa de hojarasca en las plantaciones de cacao. Para el uso a largo plazo y sustentable de plantaciones, permanentemente se deben mantener árboles de sombra podados para permitir el rejuvenecimiento del cacao y, por lo tanto, reducir presión sobre los bosques.

Copyright: © 2006 Iskandar and Erdelen. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and repro-duction in any medium, provided the original author and source are credited. The authors are responsible for the facts presented in this article and for the opinions expressed there-in, which are not necessarily those of UNESCO and do not commit the Organisation. The authors note that important literature which could not be incorporated into the text has been published follow-ing the drafting of this article. Abstract.—Indonesia is an archipelagic nation comprising some 17,000 islands of varying sizes and geologi-cal origins, as well as marked differences in composition of their floras and faunas. Indonesia is considered one of the megadiversity centers, both in terms of species numbers as well as endemism. According to the Biodiversity Action Plan for Indonesia, 16% of all amphibian an...

We estimate the phylogenetic relationships among all six recognized species of the genus Staurois based on 16S rRNA sequences (̃522 bp) for 92 specimens from Borneo and the Philippines. Our preferred phylogenetic tree inferred from Maximum Parsimony and Bayesian methods reveal six major clades within the genus leading to recognition of S. natator, S. nubilus, S. guttatus, S. tuberilinguis, S. parvus, and S. latopalmatus. For species where multiple populations were as-sessed, we found high genetic variation that may eventually support the recognition of new species.

We provide a review of Ulrich Manthey's opus 'Agamid Lizards of Southern Asia (...) - Draconinae 2, Leiolepidinae'. We correct several misidentifications of photographed individuals (in Leiolepis and Pseudocalotes), and challenge the author's synonymy of the genera Thaumatorhynchus with Harpesaurus.

Page 1. Current Herpetology 25(2): 57–63, December 2006  2006 by The Herpetological Society of Japan A New Species of Torrent-Dwelling Frog (Hylidae, Litoria) from the Mountains of New Guinea STEPHEN J. RICHARDS1* AND DJOKO T. ISKANDAR2 ...

Forty-six rodent species of the Muridae family were submitted to sequential electrophoresis for the study of 11 protein loci, using 12 buffer systems which differed in pH and ionic composition. The complete set of electrophoretic conditions yielded 135 variants of which 68 were detected through a single condition. The twofold increase of revealed variants was essentially limited to intergeneric comparisons because few additional variants within genera were revealed, despite the use of several buffers. These results show that estimation of the degree of genetic differentiation among taxa at a higher level than that of the genus by standard electrophoretic data may, although of current use, lead to erroneous results.

... 15-03-10 Donald Johanson Vicky Lee DJOKO T ISKANDAR others Page 2. The Evolution of Human Beings ... Emerged in 1987 based on a study of mitochondrial DNA (mtDNA) ▫ Rebecca Cann ▪ Genetic studies & fossil record ▫ Andrea Manica ▫ Marcus Feldman 21 Page 22. ...

Abstract We describe a new cat snake species of the genus Boiga from the Nusa Tenggara Islands, Indonesia. The new species is superficially similar to Boiga cynodon, as it was identified previously. It differs from the latter species by the following combination of ...