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Remaining forests on the Central Highlands of Madagascar—Endemic and endangered aquatic beetle fauna uncovered
No full textMadagascar is known for its high endemism and as many as 90% of this unique diversity are forest-dwellers. Unfortunately, the forest cover of Madagascar is decreasing at an alarming rate. This decrease can also affect aquatic insects, but our knowledge on aquatic insect diversity and distribution on Madagascar are limited. Although the eastern rainforests are considered the most diverse, the Central Highlands of Madagascar also harbors unique microendemic fauna but has been less studied. Here, we analyze the aquatic Adephaga beetle fauna of three remaining protected forests of the Central Highlands. Diversity, abundance, and uniqueness are compared between and within natural forests and surrounding grasslands. At least 15 undescribed species were found, highlighting the Central Highlands as an important area for endemism. The natural forests and the surrounding grasslands differed significantly in species assemblages. Interestingly, the three remaining forests differed in their assemblages with the geographically more distant Manjakatompo Ankaratra having the most unique fauna but also the highest altitude span. By contrast, the species composition was similar between the peripheral zones of each of the three remaining forests. The similarity of the fauna in the peripheral open habitats illustrates how some local forest endemics are replaced with widespread generalists in degraded habitats. Our study shows that the remaining forests of the Central Highlands of Madagascar are important refuges of unique fauna at high risk of extinction
Obituary: Dr Nathalie Nagalingum
No full textIt is with sadness that I announce to the IOP community the untimely death of our dear colleague, Dr. Nathalie Nagalingum. Nathalie passed away on August 22nd this year, surrounded by her family in Melbourne, Australia, after a long battle with ovarian cancer.Nathalie was born in Melbourne on 17th March, 1975, the daughter of Mauritian immigrants. She excelled in biological science at school and later studied botany at the University of Melbourne. She completed both her BSc Honours (in 1996) and PhD (in 2002) projects, under the supervision of Prof Andrew Drinnan and myself at that institution. Her BSc (Honours) project dealt with Early Cretaceous conifers (particularly an apparently deciduous form that she later described as Bellarinea richardsii) from the Gippsland Basin of southeastern Australia. Her PhD shifted towards an investigation of the systematics of Early Cretaceous ferns from Australia and Antarctica—incorporating material from both Museum Victoria in Melbourne and the British Antarctic Survey in Cambridge
The war in Ukraine - Its impact on palaeobotany, palynology, herbaria and museums.
No full textUkraine hosts extensive strata containing plant and algal fossils. Owing to their location on southern flank of Laurasia, Ukrainian fossiliferous deposits potentially play an important role, not only in local biostratigraphy, but also in understanding climate changes and biogeographic interchange between Europe, Africa, northern Asia, India and the Cimmerian terranes of the Mesozoic Tethys. However, much of the past work in Ukraine has been little recognized in western scientific literature, partly owing to language bariers and difficulties accessing provincial literature. Of particular note are past studies on the following fossil assemblages and regions: the Ediacaran biotas in the Dniester River area of western Ukraine; Silurian and Early Devonian plants and nematophytes from Podolia, western Ukraine; extensive Carboniferous floras associated with the coals of the Donbas region; the little-studied early Permian flora from the western Donets Basin; the rich but relatively little-known Triassic flora on the Donets Basin; Middle Jurassic palynofloras from the Dnieper–Donets Basin; Early Cretaceous megaspores and other sporomorphs from southern Ukraine; late Albian leaf and wood floras from the Kaniv area, central Ukraine; Late Cretaceous floras from western Ukraine and adjacent areas of Poland; Miocene–Pliocene macro- and palynofloras from shallow deposits of the Ukrainian Plain that are helping to build palaeoclimatic and marine incursion models for the Central and the Eastern Paratethys region; late Pliocene permineralized woods from Transcarpathian region in southwestern Ukraine; and extensive Quaternary palynofloras for studies of forest-steppe fluctuation over the past 2 million years.Ukraine has 21 major herbaria (78 in total) with >116 staff and about 4.8 million specimens. As of May, 2022, many of these are in conflict zones directly impacted by the Russian invasion. Of note, the CWU herbarium at Karazin University in Kharkiv has been damaged and the contents require urgent protection. Ukraine also hosts major palaeontological collections that are now threatened: particularly, the National Science and Natural History Museum of the National Academy of Sciences of Ukraine, Kyiv, and the National Museum of Natural History, Lviv. Staff at many of Ukraine’s museums have been busy hiding art and collections in basements, returning loans, loaning material abroad for safekeeping, and reopening the museums as bomb shelters. To support Ukrainian science and culture, funding was provided by the Swedish Royal Academy, Swedish Research Council, Swedish Strategic Fund and Collegium Palynologicum Scandinavicum for four Ukrainian palynologists to attend the 11th EPPC, and for several others to submit poster presentations. We welcome our Ukrainian colleagues to the conference
Disjunct resident population of Melodious Lark Mirafra cheniana discovered in East Africa
No full textWe describe the discovery of a previously unknown population of Melodious Lark Mirafra cheniana from northern Tanzania and southern Kenya, some 2000 km north of what was previously thought to be its northern limit in central Zimbabwe. The identification of this population as M. cheniana is based primarily on analyses of mitochondrial DNA and song. We also clarify relationships within this genus by sequencing material of White-tailed Lark Mirafra albicauda for the first time; although its relationships with other species in the group remain unclear, our analyses clearly show it to be different from M. cheniana in the newly discovered population. The discovery of a population of M. cheniana in East Africa conforms to a known pattern for closely related lark species to have disjunct distributions in southern and eastern Africa
Sediment geochemistry of the section Tagay-1 at Olkhon Island (Lake Baikal, Eastern Siberia): a contribution to palaeoenvironmental interpretations
No full textThe Miocene Tagay section in the north-western part of Olkhon Island, Lake Baikal, provides a unique window into past life in northern Asia. To aid palaeoenvironmental reconstructions, we carried out whole-rock geochemical analyses of 17 sedimentary layers of this section. The aim of this geochemical approach is to examine the element variations as a response to climate change during formation of the Tagay section deposits with a focus on the hydrological regime of the catchment and in-lake processes. Our results establish that temperature and climate conditions during the formation of sediments of section Tagay-1 were fairly stable, no abrupt climatic changes occurred. The palaeoclimate was temperate, however, it had a cyclic nature: wet and semiarid epochs of different intensity and duration alternated. The basal part of the sediment sequence is dominated by terrigeneous material, mainly by surface runoff, so the sedimentation was fed by erosion products of the weathering crust. During sedimentation of this lower part (layers 17–9), the palaeo-lake level and salinity stayed practically unchanged. The drawdown of the palaeo-lake and increasing salinity started in the higher middle part (layer 8), and reached the minimum water level and maximum salinity in layers 7–6. Sediments of the layers 8–6 accumulated in an arid climate. After deposition of layer 5, the water level began to rise, and during formation of layer 3 it fell again. The highest sedimentation rate was in layers 12–5, these are also the layers with the highest enrichment of biogenic elements (layers 12, 7–5) and where carbonate deposition took place. The observed changes in element behaviour are related to hydrological changes in the catchment (precipitation), lake level status, and evaporation, and are ultimately driven by climate.The research presented here was supported via research grants from the Russian Foundation for Basic Research (No. 20-05-00247), the Russian Science Foundation (No. 19-17-00216, sedimentology and geochemistry), and the Government of the Russian Federation (No. 075-15-2021-631), and was carried out in accordance with a State Assignment of the Vinogradov Institute of Geochemistry SB RAS (No. 0284-2021-0003). Open access funding provided by Swedish Museum of Natural History</p
Zoisite in cratonic eclogite xenoliths - Implications for water in the upper mantle
No full textA significant portion of the Earth's water is found at trace levels in nominally anhydrous rock forming minerals in the crust and mantle. Its distribution has far-reaching implications in melt-generating processes, mantle rheology and the stability of the lithosphere. We report petrographic, major and trace element, Fourier transform infrared spectroscopy and secondary ion mass spectrometry data on four eclogite xenoliths from the Obnazhennaya kimberlite, Siberia that contain hydrous minerals at upper mantle conditions. Al-rich (>9.9 wt% Al2O3) omphacitic clinopyroxene, a major mineral of eclogites, contains crystallographically controlled exsolutions of CaO-rich (up to 23.6 wt%) garnet (coronae, lenses), garnet-zoisite (lamellae) or amphiboles (needle/blade-like exsolutions). The omphacite hosting the exsolved lamellae shows enrichment or depletion in major (Al, Si, Mg) and trace (e.g., HREE) elements compatible with garnet and zoisite, proportional to the abundance of exsolutions. We argue that zoisite likely formed concomitantly with garnet exsolution from a water- and Al-rich precursory omphacite, without any fluid addition. The compositional gradients are consistent with diffusion-controlled partitioning in a closed system, and their preservation indicates the exsolution likely took place shortly prior to eclogite entrapment by the kimberlite. Large, non-exsolved, omphacite grains contain minimum ~870–1500 ppm wt. H2O (determined as OH). We infer that intertwined lamellae of hydrous garnet (600–960 ppm wt. H2O) and minor (<1%) zoisite (2 wt% H2O) formed at mantle conditions due to progressive exsolution, without external fluids. Recalculated whole rock water contents range from ~320 to 970 ppm wt. H2O. These estimates exceed by far those for the surrounding peridotitic mantle and suggest that, although a minor component, eclogites may locally be an important water reservoir in the cratonic mantle
Graphic and statistical overview of temporal trends and spatial variations within the Swedish National Monitoring Programme for Contaminants in Marine Biota (until 2020 year’s data)
No full textThis report present a graphic and statistical overview of temporal trends and spatial variations within the Swedish National Monitoring Programme for Contaminants in Marine Biota
Mummified Dicroidium (Umkomasiales) leaves and reproductive organs from the Upper Triassic of South Australia
No full textThe Leigh Creek Coal Measures incorporate unusually low-rank coals from the Upper Triassic of South Australia. Associated fluviolacustrine deposits contain well-preserved, partly mummified plant remains dominated by corystosperm seed ferns. The assemblage comprises seven species of Dicroidium, including D. odontopteroides, D. lineatum, D. dubium, D. zuberi, and Dicroidium spp. A, B and C, and associated reproductive organs, including various fragments of cupulate structures (Umkomasia sp. cf. U. quadripartita and Fanerotheca sp. cf. F. waldeckiformis) and pollen organs (Pteruchus africanus), all having excellent cuticle preservation. Based on a comprehensive analysis of more than 550 individual specimens, we (1) document diagnostic epidermal and cuticular features for foliage and reproductive organs, (2) provide an identification key for the Dicroidium species present, and (3) infer affiliations between reproductive organs and particular leaf species based on correspondence in epidermal anatomy and cuticle micromorphology and on mutual-occurrence data. Collectively, the Leigh Creek material contributes towards a more robust and realistic systematic classification of Umkomasiaceae, offers a rare chance for whole-plant reassembly of individual species, and refines reconstruction of the Dicroidium-dominated forest ecosystems in the middle to high latitudes of the Late Triassic greenhouse world
