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In the present study, we use mtDNA sequence data (cyt b gene) in combination with nuclear DNA sequences (C-mos, Rag2 genes, R35 intron), nuclear genomic fingerprints (ISSR) and morphological data to reveal species diversity within the Southeast Asian leaf turtle genus Cyclemys, a morphologically difficult group comprising cryptic species. Two morphologically distinct major groupings exist, a yellow-bellied species group with three taxa ( Cyclemys atripons, C. dentata, C. pulchristriata) and a dark-bellied species group. The latter contains besides the morphologically variable C. oldhamii three additional new species ( C. enigmatica n. sp., C. fusca n. sp., C. gemeli n. sp.). According to mtDNA data, C. fusca and C. gemeli constitute with high support the sister group of a clade comprising all other species, indicating that the dark-bellied species are not monophyletic, despite morphological similarity. mtDNA sequences of C. enigmatica, being highly distinct in nuclear genomic markers, do not differ from the sympatric C. dentata, suggesting that the original mitochondrial genome of C. enigmatica was lost due to introgressive hybridization. Morphological discrimination of Cyclemys species is possible using multivariate methods. However, gross morphology of most dark-bellied species on the one hand and of C. atripons and C. pulchristriata on the other is so similar that reliable species determination is only possible when genetic markers are used. The high diversity within Cyclemys requires revision of the IUCN Red List Categories for leaf turtles because the former assessment was based on the wrong assumption that in the entire range of the genus occurs only a single species. [ABSTRACT FROM AUTHOR]

Myrmecophytic plants utilise defensive services offered by obligate ant partners nesting in their domatia in a novel means of survival in tropical habitats. Although much is known about the ecology of myrmecophytism, there aren't enough empirical examples to demonstrate whether it substantially influences evolutionary patterns in host plant lineages. In this study, we make use of the species-rich Macaranga (Euphorbiaceae) ant-plant symbiosis distributed in the Southeast Asian Sundaland to delve into the evolutionary dynamics of myrmecophytism in host plants. We generated the most comprehensive dated phylogeny of myrmecophytic Macaranga till date using genotyping-by-sequencing (GBS). With this in hand, we traced the evolutionary history of myrmecophytism in Macaranga using parametric biogeography and ancestral state reconstruction. Diversification rate analysis methods were employed to determine if myrmecophytism enhanced diversification rates in the genus. Our results demonstrate that myrmecophytism is labile and easily lost. Ancestral state reconstruction supported a single origin of myrmecophytism in Macaranga ∼18 mya on Borneo followed by multiple losses. Diversification rate analysis methods did not yield sufficient evidence to support the hypothesis that myrmecophytism enhanced diversification rates in Macaranga; we found that topographical features on Borneo may have played a more direct role in the divergence of clades instead. Our study provides evidence that while the acquisition of domatia clearly functions as a key innovation that has enabled host plants to exploit the environment in novel ways, it may not necessarily enhance diversification rates. In fact, we hypothesise that overly specialised cases of myrmecophytism may even be an evolutionary dead end., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

We provide primer sequences for 11 new polymorphic microsatellite markers developed in the tropical ant-plant genus Macaranga (Euphorbiaceae), after enrichment cloning of Macaranga tanarius and Macaranga hypoleuca. Allele numbers per locus ranged from two to 16 among 20 accessions of M. tanarius, and from three to 10 among 22 accessions of M. hypoleuca. Observed and expected heterozygosities ranged from 0.150 to 0.900 and from 0.375 to 0.894 in M. tanarius, and from 0.545 to 1.000 and from 0.434 to 0.870 in M. hypoleuca, respectively. Six of the 11 primer pairs successfully cross-amplified polymorphic polymerase chain reaction products in Macaranga winkleri., (© 2009 Blackwell Publishing Ltd.)

We present a simple method to screen for DNA sequence variation in microsatellite- and indel-rich regions of the chloroplast genome. The single nucleotide sequence (SNS) analysis provides a trade-off between the time- and cost-effective, but less informative and homoplasy-sensitive electrophoretic detection of microsatellite and indel size variation on the one hand, and more costly, but also more accurate methods like DNA sequencing on the other. The principle of the SNS method is to sequence one instead of all four nucleotides of a target region amplified by polymerase chain reaction. By careful selection of the respective nucleotide, almost the same amount of information can be retrieved from these partial sequences as could be from complete sequences; however, only a third to a fourth of the money and time resources are needed., (© 2007 The Authors.)

An adjustment of reverberation time in rooms is often desired, even for low frequencies where passive absorbers fail. Among the active (electroacoustic) systems, incoherent ones permit lengthening of reverberation time only, whereas coherent active methods will allow sound absorption as well. A coherent-active wall lining consists of loudspeakers with microphones in front and adjustable control electronics. The microphones pick up the incident sound and drive the speakers in such a way that the reflection coefficient takes on prescribed values. An experimental device for the one-dimensional case allows reflection coefficients between almost zero and about 1.5 to be realized below 1000 Hz. The extension to three dimensions presents problems, especially by nearfield effects. Experiments with a 3 X 3 loudspeaker array and computer simulations proved that the amplitude reflection coefficient can be adjusted between 10% and 200% for sinusoidal waves at normal and oblique incidence. Future developments have to make the system work with broadband excitation and in more diffuse sound fields. It is also planned to combine the active reverberation control with active diffusion control.