Chromosomes in the African frog genus Tomopterna (Pyxicephalidae) and probing the origin of tetraploid Tomopterna tandyi.

Speciation by polyploidization has been documented to have independently occurred in 12 families of anuran amphibians. Tomopterna tandyi was described as a South African allotetraploid species of sand frogs in the family Pyxicephalidae. Recent taxonomic revisions and new species descriptions in the genus present problems with respect to the evolution of this tetraploid species. Chromosomes, mitochondrial and nuclear gene sequences, isozymes, and male mating calls were examined for T. tandyi and for diploid species of Tomopterna. Mitochondrial sequences confirmed the diploid species, T. adiastola, to be the maternal ancestor that gave rise to the tetraploid about 5 mya. Nuclear sequences and isozymes reveal a complex reticulation of paternal ancestry that may be explained by occasional hybridization of T. tandyi with diploid species of Tompoterna at various times in sympatric populations. Interspecific diploid to tetraploid gene introgression is suspected to have also occurred in Australian and North American tetraploid species of frogs. Diploid to tetraploid introgression is facilitated through triploid hybrids that are more viable than diploid hybrids and produce unreduced triploid eggs.

Sexual Dichromatism Drives Diversification within a Major Radiation of African Amphibians.

Theory predicts that sexually dimorphic traits under strong sexual selection, particularly those involved with intersexual signaling, can accelerate speciation and produce bursts of diversification. Sexual dichromatism (sexual dimorphism in color) is widely used as a proxy for sexual selection and is associated with rapid diversification in several animal groups, yet studies using phylogenetic comparative methods to explicitly test for an association between sexual dichromatism and diversification have produced conflicting results. Sexual dichromatism is rare in frogs, but it is both striking and prevalent in African reed frogs, a major component of the diverse frog radiation termed Afrobatrachia. In contrast to most other vertebrates, reed frogs display female-biased dichromatism in which females undergo color transformation, often resulting in more ornate coloration in females than in males. We produce a robust phylogeny of Afrobatrachia to investigate the evolutionary origins of sexual dichromatism in this radiation and examine whether the presence of dichromatism is associated with increased rates of net diversification. We find that sexual dichromatism evolved once within hyperoliids and was followed by numerous independent reversals to monochromatism. We detect significant diversification rate heterogeneity in Afrobatrachia and find that sexually dichromatic lineages have double the average net diversification rate of monochromatic lineages. By conducting trait simulations on our empirical phylogeny, we demonstrate that our inference of trait-dependent diversification is robust. Although sexual dichromatism in hyperoliid frogs is linked to their rapid diversification and supports macroevolutionary predictions of speciation by sexual selection, the function of dichromatism in reed frogs remains unclear. We propose that reed frogs are a compelling system for studying the roles of natural and sexual selection on the evolution of sexual dichromatism across micro- and macroevolutionary timescales.

Idiosyncratic responses to climate-driven forest fragmentation and marine incursions in reed frogs from Central Africa and the Gulf of Guinea Islands.

Organismal traits interact with environmental variation to mediate how species respond to shared landscapes. Thus, differences in traits related to dispersal ability or physiological tolerance may result in phylogeographic discordance among co-distributed taxa, even when they are responding to common barriers. We quantified climatic suitability and stability, and phylogeographic divergence within three reed frog species complexes across the Guineo-Congolian forests and Gulf of Guinea archipelago of Central Africa to investigate how they responded to a shared climatic and geological history. Our species-specific estimates of climatic suitability through time are consistent with temporal and spatial heterogeneity in diversification among the species complexes, indicating that differences in ecological breadth may partly explain these idiosyncratic patterns. Likewise, we demonstrated that fluctuating sea levels periodically exposed a land bridge connecting Bioko Island with the mainland Guineo-Congolian forest and that habitats across the exposed land bridge likely enabled dispersal in some species, but not in others. We did not find evidence that rivers are biogeographic barriers across any of the species complexes. Despite marked differences in the geographic extent of stable climates and temporal estimates of divergence among the species complexes, we recovered a shared pattern of intermittent climatic suitability with recent population connectivity and demographic expansion across the Congo Basin. This pattern supports the hypothesis that genetic exchange across the Congo Basin during humid periods, followed by vicariance during arid periods, has shaped regional diversity. Finally, we identified many distinct lineages among our focal taxa, some of which may reflect incipient or unrecognized species.

Leapfrogging into new territory: How Mascarene ridged frogs diversified across Africa and Madagascar to maintain their ecological niche.

The Mascarene ridged frog, Ptychadena mascareniensis, is a species complex that includes numerous lineages occurring mostly in humid savannas and open forests of mainland Africa, Madagascar, the Seychelles, and the Mascarene Islands. Sampling across this broad distribution presents an opportunity to examine the genetic differentiation within this complex and to investigate how the evolution of bioclimatic niches may have shaped current biogeographic patterns. Using model-based phylogenetic methods and molecular-clock dating, we constructed a time-calibrated molecular phylogenetic hypothesis for the group based on mitochondrial 16S rRNA and cytochrome b (cytb) genes and the nuclear RAG1 gene from 173 individuals. Haplotype networks were reconstructed and species boundaries were investigated using three species-delimitation approaches: Bayesian generalized mixed Yule-coalescent model (bGMYC), the Poisson Tree Process model (PTP) and a cluster algorithm (SpeciesIdentifier). Estimates of similarity in bioclimatic niche were calculated from species-distribution models (maxent) and multivariate statistics (Principal Component Analysis, Discriminant Function Analysis). Ancestral-area reconstructions were performed on the phylogeny using probabilistic approaches implemented in BioGeoBEARS. We detected high levels of genetic differentiation yielding ten distinct lineages or operational taxonomic units, and Central Africa was found to be a diversity hotspot for these frogs. Most speciation events took place throughout the Miocene, including "out-of-Africa" overseas dispersal events to Madagascar in the East and to São Tomé in the West. Bioclimatic niche was remarkably well conserved, with most species tolerating similar temperature and rainfall conditions common to the Central African region. The P. mascareniensis complex provides insights into how bioclimatic niche shaped the current biogeographic patterns with niche conservatism being exhibited by the Central African radiation and niche divergence shaping populations in West Africa and Madagascar. Central Africa, including the Albertine Rift region, has been an important center of diversification for this species complex.

The phylogenetic position and diversity of the enigmatic mongrel frog Nothophryne Poynton, 1963 (Amphibia, Anura).

The phylogenetic relationships of the African mongrel frog genus Nothophryne are poorly understood. We provide the first molecular assessment of the phylogenetic position of, and diversity within, this monotypic genus from across its range-the Afromontane regions of Malawi and Mozambique. Our analysis using a two-tiered phylogenetic approach allowed us to place the genus in Pyxicephalidae. Within the family, Nothophryne grouped with Tomopterna, a hypothesis judged significantly better than alternative hypotheses proposed based on morphology. Our analyses of populations across the range of Nothophryne suggest the presence of several cryptic species, at least one species per mountain. Formal recognition of these species is pending but there is a major conservation concern for these narrowly distributed populations in an area impacted by major habitat change. The phylogenetic tree of pyxicephalids is used to examine evolution of life history, ancestral habitat, and biogeography of this group.

The bii4africa dataset of faunal and floral population intactness estimates across Africa's major land uses.

Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species' population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate 'intactness scores': the remaining proportion of an 'intact' reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region's major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems.

Amietia angolensis and A. fuscigula (Anura: Pyxicephalidae) in southern Africa: a cold case reheated.

A study combining DNA sequences of the mitochondrial 16S rRNA gene, advertisement calls and morphology of some southern African river frogs confirms Amietia vandijki (Visser & Channing, 1997) as a good species. The form presently referred to as Amietia angolensis in southern Africa is shown to comprise two species: Amietia angolensis (Bocage, 1866) known from Angola, and Amietia quecketti (Boulenger, 1895) known from South Africa, Zimbabwe and Lesotho. Junior synonyms of A. quecketti include Rana theileri Mocquard, 1906 and Afrana dracomontana Channing, 1978. The form presently known as Amietia fuscigula is shown to consist of two distantly related taxa: Amietia fuscigula (Duméril & Bibron, 1841) from the south-western Cape and an undescribed species that we here name Amietia poyntoni sp. nov. Channing & Baptista, known from the rest of South Africa and Namibia. These five species have large differences in 16S sequences, as well as differences in morphology and advertisement call. Call and molecular data are both diagnostic, while morphology shows some overlap between taxa. An extended study of the genus across Africa is in preparation.

Identification of sand frogs (Anura: Pyxicephalidae: Tomopterna) from Kenya with the description of two new species.

African sand frogs in the genus Tomopterna presently include 13 species. These are known to be highly cryptic and morphologically similar. Despite increased effort in the recent past, the taxonomy of the group is still unresolved and some populations e.g. in Kenya have remained largely unstudied. This paper starts to address this gap using molecular, advertisement call and morphological comparisons. We test the boundaries of the Kenyan species based on mitochondrial 16S rRNA sequence data. Two new species are recognised and described: Tomopterna wambensis sp. nov. and Tomopterna gallmanni sp. nov. Further molecular and advertisement call studies of Tomopterna populations in Kenya are recommended, especially for those populations previously identified as T. cryptotis and T. tandyi.

A molecular phylogeny of African Dainty Frogs, with the description of four new species (Anura: Pyxicephalidae: Cacosternum).

We examined specimens from all eleven described species of African Dainty Frogs, Cacosternum. Advertisement calls, 16S and tyr sequences were obtained from voucher specimens of all known species plus undescribed taxa. A phylogenetic analysis indicated that there were 15 species. We describe four new species from South Africa that can be diagnosed by their advertisement calls: Cacosternum aggestum sp. nov. from the interior of the south-western Cape, the large C. nanogularum sp. nov. from KwaZulu-Natal, C. australis sp. nov. from the Western Cape Province and C. rhythmum sp. nov. from the KwaZulu-Natal midlands. Cacosternum schebeni is confirmed as ajunior synonym of C. boettgeri, and we agree that C. poyntoni is a junior synonym of C. nanum. The populations of dainty frogs on the Ethiopian highlands remain to be investigated. Shared tyr haplotypes occur between species that are not necessarily closely related, but always sympatric, at least in the recent past. This is evidence for hybridisation that requires further investigation. A provisional identification key to the species is provided.

The status of Tomopterna pulchra Boulenger, 1896 (Anura: Pyxicephalidae).

Tomopterna pulchra (Boulenger, 1896) was described from Lake Tanganyika based on a single specimen. It was synonymised with Tomopterna tuberculosa (Boulenger, 1882) by Loveridge (1957) who noted that it did not fully agree with the description of T. tuberculosa, especially in the difference in dorsal colouration. Genetic differences show that two species are confused, although their advertisement calls and morphology are similar, except for the presence of a pale vertebral stripe mostly in eastern populations. We consider the advertisement calls, morphology, and genetic differences, and remove Tomopterna pulchra (Boulenger, 1896) from the synonymy of Tomopterna tuberculosa. Divergence dating shows that these two species separated in the mid-Miocene. Tomopterna pulchra breeds in rocky habitats, whereas T. tuberculosa breeds in sandy areas, typical of the genus. Based on genetically confirmed specimens, presently T. tuberculosa is known in the west (Angola and Namibia) while T. pulchra is only known from the east (Zambia and Tanzania). The examination of specimens for the presence or absence of a vertebral stripe infers that these species are widespread. Further work is required to determine if the two species are sympatric, and the extent of their ranges.

Colour patterns to sequences: a perspective on the systematics of the Hyperolius viridiflavus group (Anura: Hyperoliidae) using mitochondrial DNA.

African reed frogs are widespread and highly polymorphic for colour pattern. The Hyperolius viridiflavus complex includes 121 described taxa, including subspecies, which are presently synonymised as 16 species. However, the taxonomy is confused as colour patterns have been used to identify species, despite an inadequate understanding of pattern variation and overlap. This study examined 267 sequences of the 16S rRNA fragment from individuals across the range of the group, from Senegal to Ethiopia, and to the southern tip of Africa. Maximum likelihood analysis showed that there were 14 species that only partially agreed with existing taxonomy. This study recognised the following species: Hyperolius viridiflavus, H. marmoratus, H. marginatus, H. parallelus, H. nitidulus, H. glandicolor, H. tuberculatus, H. mariae, H. noblei, H. goetzei, H. spatzi, H. bangwae, H. dintelmanni and an undescribed species from southern Cameroon. Hyperolius swynnertoni was found to be embedded within H. marmoratus, H. hutsebauti was embedded within H. parallelus, H. rhodesianus and H. pyrrhodictyon were embedded within H. marginatus and H. sheldricki was embedded within H. glandicolor. There was no sequence information to determine the status of Hyperolius nimbae. The ranges of the species are presented, although these are expected to change as more sequences become available. The use of DNA sequences to identify animals is recommended in this group, as the variation in advertisement calls and morphology is not well understood.

Equisetum thermale sp. nov. (Equisetales) from the Jurassic San Agustín hot spring deposit, Patagonia: anatomy, paleoecology, and inferred paleoecophysiology.

PREMISE OF THE STUDY: Dated molecular phylogenies suggest a Cenozoic origin for the crown group of Equisetum. but compression fossil equisetaleans that are morphologically indistinguishable from extant Equisetum and recently discovered anatomically preserved examples strongly suggest an earlier Mesozoic initial diversification. METHODS: In situ samples of Equisetum thermale sp. nov. from the Upper Jurassic San Agustín hot spring deposit were collected and studied with the use of polished blocks, thin sections, and light microscopy. KEY RESULTS: Equisetum thermale exhibits all the morphological and anatomical characteristics of the extant crown group Equisetum. It shows a mixture of features present in the two extant subgenera, e.g., superficial stomata typical of subgenus Equisetum allied with infrequently ramifying stems typical of subgenus Hippochaete. This appears to ally E. thermale with the least derived extant species in the genus Equisetum bogotense (sister species to the two subgenera). Its association of hydromorphic and xeromorphic characters allowed it to grow as an emergent aquatic in physically and chemically stressed geothermally influenced wetlands, where it formed dense monospecific stands. Equisetum thermale, because it is preserved in situ with intact anatomy, provides clear paleoecological, biological, plus inferred paleoecophysiological evidence of adaptations known in extant species. CONCLUSIONS: As the earliest unequivocal member of the genus, E. thermale supports the hypothesis of a Mesozoic origin. Its inferred tolerance of a similar range of stresses (e.g., high salinity, alkalinity, and heavy metal concentrations) to that seen in extant Equisetum suggests early evolution and subsequent maintenance of ecophysiological innovations in the genus.

Achieving operational efficiencies using a DRG-based tracer approach.

Hospitals can use a DRG-based tracer approach to analyze and correct inefficiencies in the flow of care delivery. The approach works best when the analysis is focused on a high-volume DRG. In the case of Mount Sinai Hospital in Chicago, this approach was instrumental in improving efficiencies of care processes associated with DRG 143: chest pain.

The role of cultural norms in shaping attitudes towards amphibians in Cape Town, South Africa.

Urban ecosystems are increasingly viewed as an important component within strategies for wildlife conservation but are shaped as much by natural systems as they are by social and political processes. At the garden scale, attitudes and preferences govern design and maintenance choices including the decision to encourage or discourage specific faunal presence. At the global scale, charismatic taxa that are well-liked attract more conservation funding and volunteer stewardship. Amphibians are a class of animals that are both loved and loathed making them a suitable subject for comparing and unpacking the drivers of preference and attitudes towards animals. We conducted a mixed methods survey of 192 participants in three adjacent neighbourhoods in Cape Town, South Africa. The survey included both quantitative and qualitative questions which were analysed thematically and used to explain the quantitative results. The results revealed that attitudes formed during childhood tended to be retained into adulthood, were shaped by cultural norms, childhood experiences and the attitudes of primary care-givers. The findings are significant for environmental education programmes aimed at building connectedness to nature and biophilic values.

The value of value-based purchasing.

In the first four years of the Hospital Quality Incentive Demonstration (HQID) project operated by the Centers for Medicare & Medicaid Improvement (CMS) and Premier, Inc., HQID hospitals improved their composite quality scores by 17.2 percent across five clinical areas. If every hospital were able to replicate this level of performance, an estimated $4.5 billion and 70,000 lives would be saved each year, according to CMS and Premier.

Correction to the type locality of Tomopterna ahli (Deckert, 1938) (Anura: Pyxicephalidae), with the designation of a neotype.

Deckert described a Tomopterna as Arthroleptella ahli from South Africa in 1938. We demonstrate that the type of Tomopterna ahli (Deckert, 1938) was actually collected in Namibia, and that this nomen is a senior synonym of Tomopterna damarensis Dawood Channing, 2002. We designate a neotype for Tomopterna ahli (Deckert, 1938).

A new sand frog from Namaqualand, South Africa (Pyxicephalidae: Tomopterna).

Tomopterna branchi sp. nov. is described from Namaqualand, South Africa. It differs from all other Tomopterna species by advertisement call, 16S rRNA sequence and consistent differences in adult morphology. The tadpole is similar to that of Tomopterna cryptotis. Haplotype networks of 16S and the nuclear tyr gene show that it is distinct from T. delalandii, with which it has been confused. A phylogeny of the genus, excluding the little-known T. monticola, shows that the new species is basal to a clade that includes T. delalandii and six other species. We extend the known range of T. damarensis to southern Namibia, and correct the identification of some GenBank material.

A review of active hot-spring analogues of Rhynie: environments, habitats and ecosystems.

The Lower Devonian Rhynie chert formed as silica sinter entombed an early terrestrial ecosystem. Silica sinter precipitates only from water flowing from alkali-chloride hot springs and geysers, the surface expression of crustal-scale geothermal systems that form low-sulfidation mineral deposits in the shallow subsurface. Active alkali-chloride hot springs at Yellowstone National Park create a suite of geothermally influenced environments; vent pools, sinter aprons, run-off streams, supra-apron terrace pools and geothermal wetlands that are habitats for modern hot-spring ecosystems. The plant-rich chert, which makes Rhynie internationally famous, probably formed in low-temperature environments at the margins of a sinter apron where frequent flooding by geothermal water and less frequent flooding by river waters created ephemeral to permanent wetland conditions. Here, the plants and associated microbes and animals would be immersed in waters with elevated temperature, brackish salinity, high pH and a cocktail of phytotoxic elements which created stresses that the fossil ecosystem must have tolerated. The environment excluded coeval mesophytic plants, creating a low-diversity hot-spring flora. Comparison with Yellowstone suggests the Rhynie plants were preadapted to their environment by life in more common and widespread environments with elevated salinity and pH such as coastal marshes, salt lakes, estuaries and saline seeps.This article is part of a discussion meeting issue 'The Rhynie cherts: our earliest terrestrial ecosystem revisited'.

A new grass frog with rupicolous tadpoles from northern Zambia (Anura: Ptychadenidae).

We describe a new species of Ptychadena from Mutinondo Wilderness in northern Zambia. It has rupicolous tadpoles that develop in a film of water. The species is distinguished on morphology, advertisement call and DNA sequences from other grass frogs and was found to be most closely related to P. broadleyi. It has no contrasting longitudinal bands on the posterior thigh, the foot is longer than half SVL, it has no light triangle on the snout, three phalanges of the fourth toe free of web and the snout has no skin folds. The species should be considered Near Threatened in terms of the IUCN Red List criteria given its limited extent of occurrence and population size.