Oligocene and Early Miocene gastropods from Kutch (NW India) document an early biogeographic switch from Western Tethys to Indo-Pacific

Shallow marine gastropod assemblages from Chattian, Aquitanian and Burdigalian sections in the Indian Kutch Basin are described. They provide insight into the composition and biogeographic relations of the gastropod assemblages at this junction between the Western Tethys and Proto-Indo-Pacific Ocean. For the first time, an improved biostratigraphy allows a clear separation of the assemblages, especially for the hitherto undifferentiated Early Miocene faunas. Throughout the Oligocene, about one-third of the species are also frequently found in the Western Tethys, documenting a passable Tethyan Seaway for nearshore molluscs. A considerable provincialism is evident as well. The expected turnover during the Early Miocene, due to the closing of the Tethyan Seaway, is reflected in the Miocene assemblages. Surprisingly, however, the cut appears very early, i.e. already during the Aquitanian, when the West–East interrelation drops to zero despite the passage having been open during this interval. In contrast, the Burdigalian assemblages witness a minor re-appearance of Western Tethys taxa, suggesting the re-establishment of rather ineffective migration pathways prior to the final closure of the Tethyan Seaway. Cerithium bermotiense and Lyria (Indolyria) maniyaraensis are introduced as new species.     

Systematic revision and palaeobiogeography of Perisphinctes Waagen (Ammonoidea) from the Oxfordian of Kutch,India: Stratigraphic and evolutionary implications

Perisphinctes Waagen, 1869 is an important genus of the Oxfordian. In many areas the taxon has been excessively and subjectively split. Based on the material collected in Kutch (India), including the type specimens, we have grouped eight species previously described as distinct into one biological species, Perisphinctes indogermanus Waagen, 1875. It is characterized by strong sexual dimorphism. Macroconch shows high intraspecific variability. Microconch is previously described from Kutch in different generic names. Thirteen species of Dichotomosphinctes Buckman, 1926, Perisphinctes Waagen, 1869 and Lithacoceras Hyatt, 1900 are considered here as microconch which is lappeted. The precise age of P. indogermanus is disputed. A detailed stratigraphic analysis of several sections in this study suggests that the species ranges from early to middle Oxfordian. Perisphinctes indogermanus is distinct from other contemporary species of the world and abundant in the Indo-Madagascan Province. Kutch population of P. indogermanus has developed virgatotome style of ribbing in juvenile stage. During the middle Oxfordian marine transgression, the species along with many other ammonites of deeper habitat of the mainland basin reached the shallow shelf of eastern fringe of the Kutch Sea. Being peripherally isolated, it soon underwent an adaptive radiation that resulted in the origination of a new family Ataxioceratidae Buckman, 1921 whose members have neotenously retained the virgatotome ribbing in adult stage. The ataxioceratids later migrated to Europe and flourished during the Kimmeridgian.     

Holocene environmental history of Lake Vuolep Njakajaure (Abisko National Park, northern Sweden) reconstructed using biological proxy indicators

Holocene environmental and climatic changes are reconstructed using analyses of biological proxies in lake sediments from Vuolep Njakajaure, a lake located near the altitudinal treeline in northern Sweden (68°20′ N, 18°47′ E). We analysed biological proxy indicators from both aquatic and terrestrial ecosystems, including diatoms, pollen and chironomid head capsules, in order to reconstruct regional Holocene climate and the development of the lake and its catchment. During the early Holocene and after 2500 cal b.p., Fragilaria taxa dominated the diatom assemblages, whereas planktonic Cyclotella taxa prevailed during the major part of the Holocene (7800–2300 cal b.p.), indicating the importance of the pelagic habitat for diatom assemblage composition. The planktonic diatoms appeared at the same time as Alnus became established in the catchment, probably altering nutrient availability and catchment stability. The pollen record is dominated by mountain birch (Betula pubescens ssp. tortuosa) pollen throughout the Holocene, but high percentage abundances of Scots pine (Pinus sylvestris) pollen suggest the presence of a mixed pine-birch forest during the mid-Holocene (6800–2300 cal b.p.). Head capsules of Tanytarsini and Psectrocladius dominated the chironomid assemblage composition throughout the Holocene, in combination with Corynocera ambigua after 2300 cal b.p. A quantitative, diatom-based reconstruction of mean July air temperature indicated a relatively cold temperature during the early Holocene (9000–8000 cal b.p.) and after ca. 2300 cal b.p., whereas the mid-Holocene period is characterised by stable and warm temperatures. The overall patterns of Holocene climate and environmental conditions are similarly described by all biological proxy-indicators, suggesting relatively warm conditions during the mid-Holocene (ca. 7800–2300 cal b.p.), with a subsequent colder climate after 2300 cal b.p. However, the onset and magnitude of the inferred changes differ slightly among the proxies, illustrating different responses to lake development phases, land-uplift, and climate forcing (e.g., insolation patterns) during the Holocene in northern Sweden.     

New costapalmate palm leaves from the Oligocene Ningming Formation of Guangxi,China, and their biogeographic and palaeoclimatic implications

New palm leaves from the Oligocene Ningming Formation are placed into the morphogenus Sabalites because of their costapalmate leaf shape. Four taxa are described on the basis of leaf compressions with cuticular structure. S. guanxiensis sp. nov. is characterised by hypostomatic leaf blades with a stout costa and a symmetrical base. Sabalites cf. asymmetricus has amphistomatic leaf blades with a long, delicate costa and an asymmetrical base. Sabalites sp. 1 has amphistomatic leaf blades with a long, massive costa and wide segments. Sabalites sp. 2 is characterized by hypostomatic leaf blades with a prominent costa and an asymmetrical base. The four new palm taxa expand our understanding of the floristic elements and features of the Oligocene Ningming flora. Together with the other three palm taxa that were previously reported from the Ningming Formation, our material indicates that the Oligocene Ningming flora had a rich diversity of costapalmate palms. The relatively high species diversity of palms and other plants corroborate that the Oligocene Ningming flora represents a warm and humid climate.     

Fossil coniferous wood from the Middle Jurassic of Liaoning Province, China

Silicified coniferous wood was collected from the Lanqi Formation (late Middle Jurassic in age) at Shebudaigou Village, Liaoning Province, China. Three taxa are identified, namely Pinoxylon dacotense Knowlton, Xenoxylon phyllocladoides Gothan, and Araucariopitys sp. Based on these new data, and those of other fossil plants reported previously from the same formation, we consider the climate during the deposition of the Lanqi Formation was subtropical, humid and seasonal. In this respect the Lanqi flora differs from the coeval Shimengou and Longmen floras from North China. The Longmen flora was deposited during more humid, subtropical conditions, while the Shimengou Formation indicates that the climate was warm temperate and dry. Our data would suggest that the Late Jurassic climatic pattern was initiated as early as the late Middle Jurassic.     

Climate response,migrational lag,and pollen representation: The problems posed by Rhododendron and Acer

Views have changed as to the relative importance of climate change and human activity on the composition of Holocene temperate forest. The ‘climate school’ maintains that temperate arboreal taxa responded swiftly to changes in Holocene climate, irrespective of dispersal mechanism, with no evidence for migrational lag or for human influence; taxa moved individualistically according to their climate response. This paper tests these tenets in two case studies. The present‐day distributions of Rhododendron and Acer in Europe are compared with earlier records, and discussed in the context of migrational lag and pollen‐climate response. Distributional data emphasise the importance of humans as a vector in aiding the spread of both Rhododendron ponticum and some Acer species in the very late Holocene. Arguably, the species concerned have exhibited extreme migrational lag; they re‐open the question as to whether the natural distributions of temperate arboreal species are in equilibrium with climate.     

Some noteworthy Desmids from Shimoga district,Karnataka State (India)

Freshwater algal collections in ponds and lakes of Shimoga district of Karnataka State (India) during 1977–1978 contained 9 Desmid taxa with interesting variations. Two new taxa belonging to Staurastrum Meyen ex Ralfs are described.     

New species and range extensions from Mt Namuli,Mt Mabu and Mt Chiperone in northern Mozambique

The three sections of this paper report on i) new species, ii) new records for the Flora Zambesiaca region and for Mozambique and iii) expansion of distributions of species previously thought to be endemic to particular mountains. Specimens have been collected from three mountains in north-central Mozambique visited during a collecting programme from 2006 to 2008 investigating the conservation value of the biodiversity of currently unprotected areas. Three new species: Crotalaria namuliensis, Isoglossa namuliensis and Helixanthera schizocalyx are described. Five taxa not previously recorded from the Flora Zambesiaca region are here recorded as new records for the region and 31 taxa are listed from Mozambique for the first time, including five taxa previously thought to be Malawi mountain endemics. The number of range extensions recorded from these Mozambican mountains is evidence of the paucity of specimens collected from this part of Mozambique and shows the need for continued collection in order to clarify the distributions of this region’s rarest species.     

Pervasive gene flow across critical habitat for four narrowly endemic,sympatric taxa

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Species delimitation and phylogeography of Abies delavayi complex: Inferred from morphological,molecular, and climatic data

The species delimitation within Abies delavayi complex, consisting of A. delavayi Franch., A. fabri (Mast.) Craib, A. nukiangensis W. C. Cheng & L. K. Fu, and A. delavayi subsp. fansipanensis (Q. P. Xiang, L. K. Fu & Nan Li) Rushforth, has been a subject of long‐term dispute. We combined different lines of evidence, including morphological characters, population‐based mitochondrial DNA and chloroplast DNA sequences, and plastome data to assess its species delimitation. These four independent datasets revealed a consistent result that the four taxa of A. delavayi complex were hardly separated and could be regarded as one species. Our results further suggested that these four taxa might have experienced rapid morphological diversification, following a common expansion triggered by climate oscillations during the Pleistocene. In addition, we surveyed the phylogeographical history of A. delavayi complex as a whole based on ecological niche models and molecular data. These results consistently revealed that this high‐mountain fir complex had experienced glacial expansion and interglacial contraction. Therefore, we propose that A. delavayi complex probably has undergone the phalanx expansion model in response to climate change during the Quaternary. Such expansion patterns demand consideration when establishing conservation strategies for threatened fir species.     

Ectothermic vertebrates (Actinopterygii,Allocaudata, Urodela,Anura, Crocodylia,Squamata) from the Miocene of Sandelzhausen (Germany,Bavaria) and their implications for environment reconstruction and palaeoclimate

The Early to Middle Miocene fossil locality Sandelzhausen has yielded 48 species of ectothermic vertebrates and thus represents one of the most diverse ectotherm faunas of Miocene age. Thirty-five taxa of fishes, amphibians and reptiles, including three new species: Pelobates fahlbuschi nov. sp. (Pelobatidae, the most abundant vertebrate), Tropidophorus bavaricus nov. sp. (Lygosominae) and Bavaricordylus molassicus nov. sp. (Cordylidae), are described. Three additional species are new, but are not named yet: Ranidae indet. nov. gen. et sp., Anguidae gen. indet. sp. nov. and Palaeoblanus sp. nov. (Amphisbaenidae). In order to reconstruct the palaeoenvironment and past hydrologic conditions, a new methodology (the tooth replacement method, TRM) is introduced, which allows for the detection of autochthonous components within freshwater fish taphocoenose. TRM is tested on 45 localities from the Upper Freshwater Molasse and gives reasonable results in agreement with other analytical approaches. It is therefore viewed as a reliable method to distinguish perennial from seasonal water conditions at the Sandelzhausen locality. Using the TRM it was demonstrated that the palaeohydrology of Sandelzhausen is characterized by a change from temporary water to permanent water conditions. During the period of temporary water conditions (units B to D1, lower part) the ecosystem was driven by seasonal inundations, and the remaining riparian pools have yielded no autochthonous fish population, but acted as spawning places for amphibians (amphibian pool). A mostly open habitat in the close vicinity, with sandy and non-groundwater-affected soils during the dry season, is suggested based on the absolute dominance of the spadefoot Pelobates fahlbuschi nov. sp. This ecosystem changed up-section (late part of unit D1 and during D2 and E) due to the establishment of permanent water conditions of riparian pond type, preserving an autochthonous Palaeocarassius/Channa fish population (fish pond). The reconstructed precipitation values suggest that the observed change in hydrologic conditions was probably driven by climate. The lower part of the section gives semi-arid/sub-humid values, with 571 mm mean annual precipitation (MAP), whereas the upper part yields sub-humid/humid values of 847 mm MAP. The increase in precipitation by about 280 mm was perhaps caused by a less seasonal precipitation regime with concomitant higher regional groundwater tables during units D2 and E. Based on the occurrence of several thermophilous reptile species, and in agreement with palaeobotanical and oxygen isotope data, the climate of Sandelzhausen is interpreted as subtropical with mean annual temperatures from 18°C to 20.8°C, mean cold month temperatures from 12.6°C to 13.3°C and mean warm month temperatures from 25.1°C to 28.1°C.     

Desert plant pollen production and a 160-year record of vegetation and climate change on the Alashan Plateau, NW China

Recent and subfossil pollen spectra from the Alashan Plateau are presented in order to provide information on desert plant representation and on recent changes in vegetation and climate in this remote area in northern China. The desert vegetation composition is faithfully represented by the surface pollen spectra. The comparison of the desert plant species to the related pollen taxa yielded the following sequence from over-representation to under-representation: Chenopodiaceae, Artemisia, Ephedra fragilis-type s.l., Reaumuria, Nitraria and Calligonum. A 72 cm long sediment record from a small hydrologically-closed inter-dune lake (SE Badan Jilin Sand Sea, southern Alashan Plateau) covering the past ∼160 years (dated by¹³⁷Cs) was analysed palynologically. Intervals of denser Artemisia coverage on the sand dunes around the lake, indicating wetter climate, occurred from the mid-1850s to the mid-1870s, during the first two decades of the 20th century and from the late 1930s to the beginning of the 1960s.     

The complete phylogeny of Pseudobulweria, the most endangered seabird genus: systematics, species status and conservation implications

Pseudobulweria is one of the least known and most endangered of all seabird genera. It comprises six taxa, of which two are extinct, three are critically endangered and one is near threatened. Phylogenetic relationships between these taxa and position of the genus in the Order Procellariiformes have never been studied, and the taxonomic status of several taxa remains unsettled. Conservation management of Pseudobulweria taxa will be enhanced if these uncertainties are resolved. We used a multilocus gene tree approach with two mitochondrial DNA markers (cytochrome oxidase subunit 1 and cytochrome b gene) and one nuclear intron (β Fibrinogen intron 7) to investigate phylogenetic relationships within the genus using sequences from all taxa. We combined gene trees to estimate a phylogeny of the genus using a multispecies coalescent methodology. We confirmed the link between Pseudobulweria and a clade comprising Puffinus and Bulweria genera. The Fiji petrel’s status, as belonging to the genus, is confirmed, as is the specific status of newly rediscovered Beck’s petrel. Maintenance of the two sub-species of Tahiti petrel as currently described is not supported. Discovering the breeding grounds of all taxa is the key for their conservation, which is vital to both the marine and fragile insular tropical ecosystems where Pseudobulweria are apical predators.     

No‐analog climates and shifting realized niches during the late quaternary: implications for 21st‐century predictions by species distribution models

Empirically derived species distributions models (SDMs) are increasingly relied upon to forecast species vulnerabilities to future climate change. However, many of the assumptions of SDMs may be violated when they are used to project species distributions across significant climate change events. In particular, SDM's in theory assume stable fundamental niches, but in practice, they assume stable realized niches. The assumption of a fixed realized niche relative to climate variables remains unlikely for various reasons, particularly if novel future climates open up currently unavailable portions of species’ fundamental niches. To demonstrate this effect, we compare the climate distributions for fossil‐pollen data from 21 to 15 ka bp (relying on paleoclimate simulations) when communities and climates with no modern analog were common across North America to observed modern pollen assemblages. We test how well SDMs are able to project 20th century pollen‐based taxon distributions with models calibrated using data from 21 to 15 ka. We find that taxa which were abundant in areas with no‐analog late glacial climates, such as Fraxinus, Ostrya/Carpinus and Ulmus, substantially shifted their realized niches from the late glacial period to present. SDMs for these taxa had low predictive accuracy when projected to modern climates despite demonstrating high predictive accuracy for late glacial pollen distributions. For other taxa, e.g. Quercus, Picea, Pinus strobus, had relatively stable realized niches and models for these taxa tended to have higher predictive accuracy when projected to present. Our findings reinforce the point that a realized niche at any one time often represents only a subset of the climate conditions in which a taxon can persist. Projections from SDMs into future climate conditions that are based solely on contemporary realized distributions are potentially misleading for assessing the vulnerability of species to future climate change.     

Reconstruction of late-glacial and holocene environments in southeast France based on the study of a 66-m long core from Biot, Alpes Maritimes

A pollen analytical study of a 66-m long core from the Brague valley, Biot, Alpes-Maritimes, France, suggests that thalwegs in eastern Provence may have served as refugia for mesophilous trees such asTilia, Fagus andAbies during the last glacial period. During the Younger Dryas the vegetation was considerably less steppic in character than that described from western Provence. The varying role of taxa such asQuercus ilex-type in pollen profiles from the wider region suggests a longitudinal gradient in both climate and vegetation development in the French/Italian north-western meditcrranean region during the Holocene.     

Studies in selected fragilarioid diatoms (Bacillariophyceae) from Lake Hovsgol, Mongolia

Three fragilarioid diatom taxa were studied in detail at the light microscopy and scanning electron microscopy levels from samples collected from Lake Hovsgol, Mongolia. Two of the taxa are new to science, described here as Staurosirella minuta Morales et M. B. Edlund and Pseudostaurosira tenuis Morales et M. B. Edlund, and may be endemic to Lake Hovsgol. The third taxon has been identified as Fragilaria polonica Witak et Lange‐Bertalot and it is transferred to the genus Pseudostaurosira (Grunow) D. M. Williams et Round as Pseudostaurosira polonica (Witak et Lange‐Bertalot) Morales et M. B. Edlund comb. nov. based on the ultrastructural features of its valves. The relationship of the above taxa to others reported in the literature is included herein, and the nomenclatural transfer, Pseudostaurosira naveana (Le Cohu) Morales et M. B. Edlund comb. nov., is proposed.     

Cypsela micromorphology and anatomy in Cirsium sect. Epitrachys (Asteraceae,Carduoideae) and its taxonomic implications

Cirsium Miller, one of the largest genera of the Asteraceae (Carduoideae), contains more than 250 taxa. Turkey is one of its diversity centers and according to recent studies this genus is represented by 80 taxa. In the present study, cypsela morphologies, micromorphologies and anatomical structures of 17 C. sect. Epitrachys taxa distributed in Turkey are characterized in detail by using stereomicroscope, light microscope (LM) and scanning electron microscope (SEM). Cypselas are found to be obovate to narrowly oblong, or rarely oblanceolate. Based on SEM characters, six cypselas surface ornamentation types are identified, pericarp anatomical structures are described, as well as the structure of the testa. Crystal formations were observed in three taxa and secretory materials in the mesocarp were evaluated. Data obtained from this study are compared with previously published results and it is concluded that fruit micromorphological and anatomical characters are useful for the delimitation of taxa in Cirsium and may be useful for supraspecific classification.     

Peltoceratinae (Ammonoidea) from the upper Callovian–lower Oxfordian of Kutch,India: Systematic revision and biostratigraphic implication

The ammonoid subfamily Peltoceratinae is a well-constrained group restricted to the Middle Upper Jurassic; it had a near global distribution. In Kutch (India), they were the most important marine macroinvertebrate group during the upper Callovian–lower Oxfordian. Previous reports suffered from excessive splitting due to failure to account for the large intraspecific variability and sexual dimorphism of these ammonoids. The present systematic revision, based on numerous specimens including many near-complete adult specimens, enables to recognize and describe three species of the genus Peltoceras (P. athleta, P. ponderosum, and P. kumagunense) and two species of the genus Peltoceratoides (P. semirugosus and P. propinquus), as well as identifying their macroconchs and microconchs. We rediscovered Peltoceras athleta, which was previously described by Waagen (1875) but often overlooked by subsequent workers. We were able to identify several morphs within this species that are stunningly similar with those previously reported from France. The presence of P. athleta sensu stricto prompted us to reinstate the Athleta Zone in Kutch, improving intercontinental biostratigraphic correlation. Also, it highlights that the genus Peltoceras has a different biostratigraphic longevity in Kutch: in Europe it is restricted to the upper Callovian, whereas in India it also occurs in the lower Oxfordian.     

Tumbleweed (Salsola, section Kali) species and speciation in California

Tumbleweeds (Salsola species, section Kali) are road side and rangeland pest plants throughout the 48 contiguous states in the US. Three described tumbleweed species and two undescribed Salsola taxa occur in California. The known species are Russian thistle, Salsola tragus, introduced from Eurasia in the 1800s, Russian barbwire thistle, S. paulsenii, which grows in the desert regions of California, and is also native to Eurasia, and the recently identified S. kali subspecies austroafricana, possibly native to South Africa. Our goals were to investigate karyology, genome size, and molecular genetic affinities of the described species and the other taxa within their ranges in California using recently developed microsatellite loci, dominant nuclear DNA markers (RAPD and ISSR), and DNA sequence data. Chromosome counts and genome size assessments made with flow cytometry were compared. These analyses indicated that one undescribed taxon is a new allopolyploid hybrid between S. tragus and S. kali subspecies austroafricana, and the other undescribed taxon appears to be a complex hybrid involving all three described species. The invasion potentials for the hybrid taxa are unknown. Tumbleweeds are the focus of biological controls efforts but the identification of suitable agents for the hybrid taxa may be problematic because of the large amount of genetic variability encompassed within this evolving Salsola complex.