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The spatial distribution of a species' genetic diversity can provide insights into underlying evolutionary, ecological and environmental processes, and can contribute information towards the delineation of conservation units. The Knysna seahorse, Hippocampus capensis, is endangered and occurs in only three estuaries on the warm-temperate south coast of South Africa: Knsyna, Keurbooms and Swartvlei. Population sizes in the latter two estuaries have been very small for a prolonged period of time, and the populations residing in them may thus benefit from translocations as a means of increasing population sizes and possibly also genetic diversity. However, information on whether these three estuaries constitute distinct conservation units that warrant separate management is presently lacking. Here, we used genetic information from mitochondrial (control region) and nuclear microsatellite loci to assess the genetic diversity and spatial structure across the three estuaries, and also whether translocations should be included in the management plan for the Knysna seahorse. Although each population had a unique combination of alleles, and clustering methods identified the Swartvlei Estuary as being distinct from the others, levels of genetic admixture were high, and there was no evidence for reciprocal monophyly that would indicate that each estuary has a unique demographic history. On these grounds, we suggest recognising the three populations as a single evolutionarily significant unit (ESU), and encourage translocations between them to ensure the species' long-term survival. [ABSTRACT FROM AUTHOR]

The Wild Coast in south-eastern South Africa is strongly influenced by the warm, southward-flowing Agulhas Current. This current has a significant impact on dispersal in the coastal biota of the region, and facilitates high levels of connectivity among populations. However, it is not known how the region's high-velocity hydrology affects genetic population structure in endemic estuarine species, populations of which are frequently isolated from the sea. Here, we compared genetic structure in two estuarine crabs of the family Hymenosomatidae. Both are presumed to have low dispersal potential, but they differ in terms of their life histories.Hymenosoma longicrurehas abbreviated larval development and can complete its entire life cycle within estuaries, whereasNeorhynchoplax bovisis a direct developer that lacks planktonic larvae. Using DNA sequence data from the mitochondrial COI gene and the intron of the nuclear ANT gene, we found that levels of genetic structure differ considerably between the species. Depending on the genetic marker used,H. longicrureis genetically homogeneous (COI) or displays low levels of genetic structure and minor evidence of recruitment near natal sites (ANT). In contrast, connectivity inN. bovisis much lower, as this species has a unique combination of alleles at each site, indicating that recruitment is mostly local. These results support previous findings suggesting that even a short larval dispersal phase is sufficient to maintain high levels of connectivity and prevent genetic divergence among populations. [ABSTRACT FROM AUTHOR]

An unidentified monogenean diplozoid species was collected from the gills of moggel in the Vaal River and Vaal Dam, South Africa. Specimens were removed from gills of the hosts and observed using light and electron microscopy to compare these diplozoids with known species. The second internal transcribed spacer (ITS2) of the ribosomal gene was amplified, sequenced and compared to that of other diplozoid taxa. Morphological species delimitation was used to determine the identity of these diplozoids, but they did not match the description of any diplozoid taxa. This species is recognized by the specific size of the hooks, number of plicae in posterior and trapezoid anterior projection of the median sclerite connecting to the clamp jaws via a single sclerite, occasionally with two small additional sclerites. Genetic characteristics based on sequence data from the ITS2 region also distinguish this taxon from all other diplozoid taxa. This South African diplozoid grouped in the same clade as Paradiplozoon ichthyoxanthon Avenant-Oldewage, 2013. Data clearly indicate that diplozoids collected from moggel represent a new, distinct taxon of Paradiplozoon Akhmerov, 1974 and are described here as Paradiplozoon vaalense n. sp. [ABSTRACT FROM PUBLISHER]

A new species, Paradiplozoon ichthyoxanthon (Monogenea: Diplozoidae) is described from the gills of Labeobarbus aeneus (Cyprinidae) in the Vaal Dam and Vaal River Barrage in the Vaal River, South Africa. This species is the first in this genus from southern Africa; Paradiplozoon aegtyptense and Paradiplozoon ghanense have been described from northern Africa. The new species differs from all other Paradiplozoon species on the basis of the combination of morphological characteristics, namely disk-like haptor, eggs without filaments, clamp and central hook morphology and size of specimens. The species description is accompanied by a description of the reproductive organs. The internal transcribed spacer of the ribosomal gene (ITS2) was studied and the South African individuals formed a distinct clade, supporting the establishment of a new species. [ABSTRACT FROM PUBLISHER]

Collembola is one of the major functional groups in soil as well as a model taxon in numerous disciplines. Therefore the accurate identification of specimens is critical, but could be jeopardised by cases of cryptic diversity. Several populations of six well characterised species of springtails were sequenced using the COI barcode fragment as a contribution to the global Collembola barcoding campaign. Each species showed high intraspecific divergence, comparable to interspecific sequence divergence values observed in previous studies and in 10 congeneric species barcoded here as a reference. The nuclear marker, 28S, confirmed all the intraspecific lineages found with COI, supporting the potential specific status of these entities. The implications of this finding for taxonomy and for disciplines relying on species names, such as evolution and ecology, are discussed. [ABSTRACT FROM AUTHOR]

The boky-boky, Mungotictis decemlineata, is an endemic and presumed forest-dependent carnivoran species restricted to lowland central western Madagascar. It inhabits dry deciduous forests, which have been severely reduced in surface area with ∼60% destroyed or degraded by humans during the past 60 years. M. decemlineata is limited to the remnant forests of the central and southern Menabe, and using samples collected from sites across this zone, a phylogeographic study was conducted based on two mitochondrial (1140 base pairs [bp] of cytochrome b and 563 bp of the control region) and one nuclear fragment (591 bp of the seventh intron of the fibrinogen gene). Forty-seven individuals were included from the central Menabe from four principal localities and two animals from the southern Menabe from a single locality. Low sequence divergence (1.65% for the combined fragment, 4.26% for the control region and 0.78% for cytochrome b) characterized specimens across a zone of 130 km delimited by the Tsiribihina River to the north and the Mangoky River to the south; this area includes most of the geographical range of M. decemlineata. Phylogenetic trees, haplotype networks and exact test of population differentiation did not reveal any meaningful geographic partitioning of genetic variation. However, shallow yet significant genetic structure was revealed by Φ ST calculations for the combined as well as separate DNA fragments, which we ascribe to isolation-by-distance. We proposed two different scenarios to explain the lack of meaningful phylogeographical structure in Mungotictis: (1) for this forest-dependent species, dispersal during periods of more continuous forest cover gave rise to a genetic meta-population or (2) that it is able to cross non-forested zones and broadly disperses, leading to high levels of genetic homogeneity. Current inferences favour the first hypothesis. The short- and medium-term future of this taxon is in jeopardy associated with habitat destruction across its geographical range. [ABSTRACT FROM AUTHOR]

The numbers of black rhino Diceros bicornis in Africa declined dramatically during the last century due primarily to poaching and latterly habitat transformation and fragmentation and as such, significant concerns exist with regard to the long-term population viability and the management of these fragmented populations. A considerable proportion of the remaining black rhino (ssp. minor) are found within South Africa where they largely fall under the protection and management of Ezemvelo KwaZulu-Natal (KZN) Wildlife. Here we provide information on the genetic diversity, population differentiation and level of inbreeding among 77 Diceros bicornis minor individuals sampled in seven protected areas within the KZN Province of South Africa and a single population from Zimbabwe founded from the KZN population. For reference purposes with the cluster analyses, we included four individuals from ssp. bicornis and four individuals from ssp. michaeli. We found low levels of differentiation among ssp. minor populations across the KZN Province; this result is not unexpected given the history of establishments and translocations between reserves. In fact, we argue that the translocations conducted by Ezemvelo KZN Wildlife have contributed to the acceptable levels of heterozygosity and minimal inbreeding which characterize the majority of protected areas in the province. Although the overall genetic diversity in D. b. minor is lower than that present in both Diceros bicornis bicornis and Diceros bicornis michaeli, we do not feel that it is any cause for concern at this stage as it still falls within the range reported for other large mammals across Africa. The information presented here forms the basis of an ongoing monitoring programme aimed at providing vital information which, when taken with ecological and other data, will direct the future management decisions regarding translocations between reserves in South Africa and the exchange of individuals with other countries. [ABSTRACT FROM AUTHOR]

The threat posed by biological invasions is well established. An important consideration in preventing the spread of invasives and also subsequent introductions lies in understanding introduction pathways. The Democratic Republic of the Congo (DRC) houses a large percentage of the world's biodiversity, yet no national strategy exists to deal with the growing number of invasive alien species. Amongst these are the house mouse and ship and Norwegian rats. By comparing our result to published data, we show that species were possibly introduced into the DRC via two routes. The first is via the western seaport at Kinshasa where specimens of M. m. domesticus and R. rattus on the western and northwestern side of the DRC show ties with European haplotypes. The second is via the east where specimens of R. rattus appear linked to Arab and southeast Asian haplotypes. Future work should consider more comprehensive sampling throughout the DRC to more accurately investigate the occurrence of invasive species throughout the country as well as extend sampling to other African countries. [ABSTRACT FROM AUTHOR]

Small to medium-sized central African forest artiodactyls constitute a diverse yet heavily hunted group composed primarily of species within the genera Cephalophus, Neotragus, Tragelaphus and Hyemoschus. Of these genera, Cephalophus is the richest with as many as seven sympatric species known to occur in central African forests. However, differentiating species from their faeces or from tissue where the whole carcass is unavailable is very difficult. In order to develop a robust molecular diagnostic for species identification, a database of mitochondrial cytochrome b (553 bp) and control region (∼675 bp) sequences was compiled from all forest Cephalophus species and other similarly sized, sympatric Tragelaphus, Neotragus and Hyemoschus species. Reference phylogenies from each marker were then used to recover the identity of sequences obtained from unknown faecal samples collected in the field. Results were then compared to determine which region best recovered species identity with the highest statistical support. Restriction fragment length polymorphisms (RFLPs) were also assessed as an alternative method for rapid species identification. Of the methods examined, tree-based analyses built on a geographically comprehensive database of control region sequences was the best means of reliably recovering species identity from central African duikers. However, three sister taxa appear indistinguishable ( Cephalophus callipygus, Cephalophus ogilbyi and Cephalophus weynsi) and not all species were monophyletic. This lack of monophyly may be due to incomplete lineage sorting commonly observed in recently derived taxa, hybridization or the presence of nuclear translocated copies of mitochondrial DNA. The high level of intra-specific variation and lack of robust species-specific diagnostic sites made an RFLP-based approach to duiker species identification difficult to implement. The tree-based control region diagnostic presented here has many important applications including fine-scale mapping of species distributions, identification of confiscated tissue and environmental impact assessments. [ABSTRACT FROM AUTHOR]

Standard test species may differ in their response to toxicants. Accurate identification of test organisms is therefore of critical importance in correctly interpreting data generated from laboratory assays. This is not always possible when species are morphologically similar or where the taxonomy of the group has recently been revised. A case in hand concerns Eisenia sp. Based on recent genetic evidence two species, Eisenia andrei and Eisenia fetida, which were previously considered a single species, are currently recognized. In these instances, DNA barcoding, demonstrated and discussed herein, provides a method to accurately identify test organisms. [ABSTRACT FROM AUTHOR]

On the basis of molecular and morphological evidence, Mormopterus acetabulosus, hitherto considered an endemic to the Mascarene Islands (Mauritius and La Réunion), is shown to comprise 2 closely related taxa. The holotype of M. acetabulosus is from Mauritius and the new taxon described herein is from La Réunion. M. acetabulosus from Mauritius is notably larger than members of this genus from La Réunion, and several soft-part and cranial characters distinguish these 2 taxa. This conclusion is supported by examination of mitochondrial DNA control region data for 141 bats, which shows these 2 groups to be reciprocally monophyletic, separated by an average of 5.01% uncorrected sequence divergence. Two nuclear intron regions (7th intron of the beta fibrinogen gene and thyrotropin) also were included, but showed limited genetic variation and no fixed differences between the 2 taxa. These 2 species of Mormopterus are common on Mauritius and La Réunion, often living in caves or synanthropically, and are not considered a conservation concern. [ABSTRACT FROM AUTHOR]

Elephant-shrews (also called sengis, order Macroscelidea) are small-bodied insectivorous mammals with a strictly African distribution. Fifteen species currently are recognized, of which 9 occur in the southern African subregion. On the basis of molecular, cytogenetic, and morphological evidence, Elephantulus edwardii, the only strictly South African endemic species, is shown to comprise 2 closely related taxa. The new Elephantulus taxon described herein is from the central Nama-Karoo region of Western Cape and Northern Cape Provinces. Important genetic distinctions underpin its delimitation. Sequence data from the mitochondrial cytochrome-b gene and the hypervariable control region as well as 7th intron of the nuclear fibrinogen gene show these 2 taxa to be reciprocally monophyletic. They are separated by 13.8% sequence divergence (uncorrected) based on the 2 mitochondrial segments, and 4.2% based on the nuclear intron sequences. In addition, fixed cytogenetic differences include a centromeric shift, heterochromatic differences on autosomal pairs 1-6, and the number of nucleolar organizer regions. The new species has several subtle morphological and phenotypic characters that distinguish it from its sibling species E. edwardii, the most striking of which is the presence of a tail-tuft, as well as the color of the flanks and the ventral pelage. The abundance, detailed distribution of the new form, and its life-history characteristics are not known, and further studies clearly are needed to determine its conservation status. [ABSTRACT FROM AUTHOR]

The patterns in and the processes underlying the distribution of invertebrates among Southern Ocean islands and across vegetation types on these islands are reasonably well understood. However, few studies have examined the extent to which populations are genetically structured. Given that many sub-Antarctic islands experienced major glaciation and volcanic activity, it might be predicted that substantial population substructure and little genetic isolation-by-distance should characterize indigenous species. By contrast, substantially less population structure might be expected for introduced species. Here, we examine these predictions and their consequences for the conservation of diversity in the region. We do so by examining haplotype diversity based on mitochondrial cytochrome c oxidase subunit I sequence data, from two indigenous ( Cryptopygus antarcticus travei, Tullbergia bisetosa) and two introduced ( Isotomurus cf. palustris, Ceratophysella denticulata) springtail species from Marion Island. We find considerable genetic substructure in the indigenous species that is compatible with the geological and glacialogical history of the island. Moreover, by employing ecological techniques, we show that haplotype diversity is likely much higher than our sequenced samples suggest. No structure is found in the introduced species, with each being represented by a single haplotype only. This indicates that propagule pressure is not significant for these small animals unlike the situation for other, larger invasive species: a few individuals introduced once are likely to have initiated the invasion. These outcomes demonstrate that sampling must be more comprehensive if the population history of indigenous arthropods on these islands is to be comprehended, and that the risks of within- and among-island introductions are substantial. The latter means that, if biogeographical signal is to be retained in the region, great care must be taken to avoid inadvertent movement of indigenous species among and within islands. Thus, quarantine procedures should also focus on among-island movements. [ABSTRACT FROM AUTHOR]

The Neotropics contributes significantly to global biodiversity yet little is known about its mammalian fauna. Given our limited knowledge, concerns are that extinctions at the local level may cause a decline in genetic diversity through the loss of unique alleles. Here we report the geographical population structure of four rodent species from French Guiana: Dasyprocta leporina, Agouti paca, Proechimys cayennensis and P. cuvieri. Two of them ( Dasyprocta and Agouti) are commonly harvested throughout the country for subsistence and/or game hunting. Cytochrome b and control region sequences revealed the presence of a number of maternal lineages occurring in sympatry throughout French Guiana. We applied two cytochrome b rodent clock calibrations (7.5% and 12% per million years) to our data, and placed the divergence of the maternal lineages to between 160 000 and 260 000 years ago for the more diverse D. leporina and P. cuvieri, and between 66 000 and 46 000 years ago for the more recent A. paca and P. cayennensis. The clades appear to be widespread throughout South America as indicated by specimens sampled in Brazil, Peru, and Venezuela. At the population level, AMOVA revealed little or no geographical structure within French Guiana. However, this conclusion is based on a single genetic marker and relatively few specimens. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society, 2004, 81, 203–218. [ABSTRACT FROM AUTHOR]

Phylogeographic structure was determined for the yellow mongoose, Cynictis penicillata, using mtDNA RFLPs and control region sequences. The RFLP analysis revealed 13 haplotypes which showed weak geographical patterning consistent with a recent range expansion from a refugial population(s). An analysis of molecular variance (AMOVA) revealed no correspondence between mtDNA phylogeography and subspecies delimitation, nor between matrilines and areas characterized by a high incidence of the viverrid-type rabies, of which the yellow mongoose is the principal vector. The lack of structure was also shown by control region sequences although four of the maternal lineages shared a near-perfect 81 bp repeat. We speculate that regional hot spots of the viverrid rabies biotype reflect population density differences in the yellow mongoose that are not underscored by genetic partitioning, at least at the level of resolution provided by our analyses. [ABSTRACT FROM AUTHOR]

Omicron Aquarii is a late-type, Be shell star with a stable and nearly symmetric Hα emission line. We combine Hα interferometric observations obtained with the Navy Precision Optical Interferometer covering 2007 through 2014 with Hα spectroscopic observations over the same period and a 2008 observation of the system's near-infrared spectral energy distribution to constrain the properties of o Aqr's circumstellar disk. All observations are consistent with a circumstellar disk seen at an inclination of 75° ± 3° with a position angle on the sky of 110° ± 8° measured East from North. From the best-fit disk density model, we find that 90% of the Hα emission arises from within 9.5 stellar radii, and the mass associated with this Hα disk is ∼1.8 × 10−10 of the stellar mass, and that the associated angular momentum, assuming Keplerian rotation for the disk, is ∼1.6 × 10−8 of the total stellar angular momentum. The occurrence of a central quasi-emission feature in Mg ii λ4481 is also predicted by this best-fit disk model and the computed profile compares successfully with observations from 1999. To obtain consistency between the Hα line profile modeling and the other constraints, it was necessary in the profile fitting to weight the line core (emission peaks and central depression) more heavily than the line wings, which were not well reproduced by our models. This may reflect the limitation of assuming a single power law for the disk's variation in equatorial density. The best-fit disk density model for o Aqr predicts that Hα is near its maximum strength as a function of disk density, and hence the Hα equivalent width and line profile change only weakly in response to large (factor of ∼5) changes in the disk density. This may in part explain the remarkable observed stability of o Aqr's Hα emission line profile. [ABSTRACT FROM AUTHOR]