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Open access in a taxonomic sense: a morphological and molecular guide to Western Palaearctic Dusona (Hymenoptera, Ichneumonidae)
No full textIn the present time of biodiversity crisis, assessing species diversity by accurate and accessible taxonomic revisions is more crucial than ever. Parasitoid wasps are considered as both one of the most diverse and under-studied groups in the tree of life. Dusona Cameron, 1901 (Ichneumonidae, Campopleginae) is with 442 species one of the most species - rich genera of Darwin wasps, but despite the existence of recent keys, species identification has proven difficult to impossible to non-specialists. In this study, we exam- ined about 1,500 Dusona specimens from recent and historical collections in Sweden and Switzerland. We provide a photographic guide to diagnostic characters and detailed plates for 57 out of 125 Western Palaearctic Dusona species, facilitating species identification based on existing keys. We add 11 and 3 species to the faunistic records of Sweden and Switzerland, respectively. Furthermore, we reconstruct the phylogeny of European Dusona based on four standard markers (COI, CAD, ITS2, 28S) for 45 species, complemented with a reliable reference barcode library for 46 species. Even though we can identify sev- eral morphologically distinct clades, we do not propose any new subgenera due to prevalent homoplasy of characters. While most species are well separated by barcodes, several morphologically distinct species have barely discriminatory barcode sequences (p-distances < 2%) or are even paraphyletic in this marker, indicating limitations in the applicability of barcodes for Darwin wasps. This study reveals severe gaps in the inventories of neglected taxa even for well-studied countries such as Sweden and Switzerland. As this study makes species determination for Western Palaearctic Dusona more accessible, we encourage more people, including non-specialists, to work with this genus.iadegma parasitoid wasps in Sweden (Hymenoptera, Ichneumonidae): unravelling the unknow
Deep origin of the crossed‐lamellar microstructure in early Cambrian molluscs
No full textAragonitic crossed-lamellar (CL) is one of themost commonly formed and extensively studied molluscanshell microstructures, yet its origin and early evolution within the Mollusca remains poorly understood. Here, a primitive CL microstructure from one of the oldest gastropods,Pela-giella madianensis, and the problematic hyolith Cupitheca sp. of the Cambrian Series 2 Xinji Formation on the North China Platform, was investigated. In P. madianensis, detailed characterization has revealed a typical four-ordered hierarchical orga-nization of aragonitic crystallites, and a thick layer of organic membranes surrounding its first-order lamellae. A transitional fibrous microstructure was observed between the outer CL and inner foliated aragonite structural layers. In Cupitheca sp.,only the first and second-order lamellae were visible due to preservation limitations, and the first-order lamellae were extremely irregular in shape and size, which is consistent with modern representatives. This study demonstrates that the capability to construct highly-mineralized intricate shells was acquired in early Cambrian stem-group gastropods. The CL microstructure first emerged in the early Cambrian and as a basal synapomorphic trait in total-group molluscs. Moreover, presence of the CL microstructure in problematic lophotrochozoans (i.e.hyoliths) is confirmed. This study contributes to a more complete picture of the evolutionary origin andarchitectural diversity of biomineralized mollusc shells during the Cambrian explosion, and strengthens the phylogenetic links between hyoliths and molluscs.This research was funded by the National Natural Science Foundation of China (Grant nos. 41930319, 41890845, 42102012, 41621003 and 42072003); Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB26000000), 111 Project (Grant No. D17013), Swedish Research Council (Grant nos. VR2016-04610 and VR2017-05183) a Young Thousand Talents Plan of China (Grant No. 41720104002) and China Postdoctoral Science Foundation (Grant No. 2022M712987). </p
Hyolithid-like hyoliths without helens from the early Cambrian of South China, and their implications for the evolution of hyoliths
No full textBackground: A small hyolith, with a triangular operculum and a conical-pyramidal conch with a sharp apex, originally documented as Ambrolinevitus ventricosus, is revised based on new material from the Chengjiang biota. The operculum of ‘Ambrolinevitus’ ventricosus displays strong morphological similarities with the operculum of Paramicrocornus from the Shuijingtuo Formation (Cambrian Series 2), indicating that the species should be reassigned to Paramicrocornus. Results: Based on the unusual morphology of Paramicrocornus, we herein propose a new family Paramicrocornidae fam. nov. A cladistic analysis of Cambrian and Ordovician hyoliths clearly delineates hyolithids as a monophyletic group which evolved from the paraphyletic orthothecids in the early Cambrian and with Paramicrocornidae as its closest relative. Conclusions: The phylogenetic analysis, together with the distribution of hyoliths from the Cambrian to the Ordovician, reveals the presumptive evolution model of both the skeleton and soft-part anatomy of hyoliths. The Family Paramicrocornidae plays an intermediate role in hyolith evolution, representing the transitional stage in the evolution from orthothecids to hyolithids.This work was supported from the National Natural Science Foundation of China [Grants 41720104002, 41890844, and 41621003 to ZZF, 41772002 to CBS], the Strategic Priority Research Program of the Chinese Academy of Sciences to the Early Life Institute [XDB26000000] and Overseas Expertise Introduction Centre for Discipline Innovation [111 Center: D17013] for the continuous fossil collections of the Xi’an group are sincerely acknowledged. This work was also funded by the Swedish Research Council to CBS [VR2016-04610] and TPT [VR2017-05183] and Young Thousand Talents Plan of China and National Science Foundation of China grant to TPT [42072003]. ZZF acknowledges the Changjiang Scholars [T2016155 to ZZF], Department of science and technology of Shaanxi Province [2022TD-11] and Wanrenjihua programmes [W03020685 to ZZF] for continuous supports for his laboratory and field works.</p
Lab intercalibration for chlorinated, brominated,and perfluorinated substances in biota –freshwater and marine monitoring programmes
No full textWildfires and Monsoons: Cryptic Drivers for Highly Variable Provenance Signals within a Carboniferous Fluvial System
No full textIdentification key to and checklist of the Swedish Phlaeothripidae (Thysanoptera)
No full textThe Swedish fauna of thrips (Thysanoptera) in the family Phlaeothripidae consists of 49 species. A key to the species of Phlaeothripidae found in Sweden is provided. One species is recorded as new for the country, and 10 new regional records are presented. A checklist of all Swedish tubuliferan species with regional distributions is also given.The Swedish diversity of the thrips family Phlaeothripidae (Thysanoptera), and mitochondrial delimitation and identification of thrips specie
Amphibian and reptilian fauna from the early Miocene of Echzell, Germany
No full textThe present study describes a rich amphibian and reptilian assemblage from the early Miocene locality Echzell, Germany. It consists of one allocaudate, five salamander, five frog, one gecko, chamaeleonids, anguine lizards, one lacertid, one skink and five snake taxa. The entire herpetofauna of Echzell is represented by genera and/or families very broadly known from the early Miocene of Europe. Contrary to other early Miocene herpetofaunas, the Echzell assemblage includes surprisingly only one form of crocodile-newts (Chelotriton). The Echzell Palaeobatrachus robustus represents the youngest record of the species and extends its stratigraphic range to the late early Miocene. Regarding chameleons, the frontal is partly preserved, but represents the first described frontal of the extinct species Chamaeleo andrusovi. The only anguine lizard that can be identified in the assemblage is represented by a new genus and species Smithosaurus echzellensis. Our phylogenetic analyses consistently recovered it as the sister taxon to either [Ophisauriscus quadrupes + Ophisaurus holeci] + [Anguis + Ophisaurus] (in the first analysis) or [Anguis + Ophisaurus] (in the second analysis). However, the results are based on limited fossil material – the parietal – and the support for the clade is very low. Thus, the interpretation of the Smithosaurus relationship among anguines needs to be taken with caution and has to be tested in further studies. Among snakes, Natrix longivertebrata represents the oldest record of the species and extends the stratigraphic range of this fossil snake back to the early Miocene. In addition, we provide here a broader comparison of the Echzell amphibian and reptilian assemblage with their European records for the MN3 and MN4 biostratigraphical units. Besides that, the entire herpetofauna of Echzell includes very broadly known early Miocene European forms. Remains of other groups of the same period such as Bufonidae, Hylidae, Pelodytidae, Amphisbaenia, Varanidae, Cordylidae, Pseudopus, are not found in the material available to us. We also conclude that the amphibian and reptilian fossil record across MN3–MN4 is significantly biased by taphonomic and/or environmental conditions. The amphibian and reptilian assemblage of Echzell is rich in forms living in humid and warm environments with forested areas, permanent water bodies and also some open habitats. The following climatic parameters can be reconstructed based on the herpetofauna: a mean annual temperature of 17.4–28.8 °C, minimal warm month temperature 18–28.3 °C, minimal cold month temperature 8–22.2 °C, and mean annual precipitation with a value of 791±254 mm.A.Č. acknowledges financial support from the Scientific Grant Agency of the Ministry of Education of the Slovak Republic and Slovak Academy of Sciences, Grant Nr. 1/0191/21. T.M. acknowledges financial support from the Bolin Center for Climate Research, Stockholm University (RA6 grant).</p
Incisor enamel microstructure places New and Old World Eomyidae outside Geomorpha (Rodentia, Mammalia)
No full textThe lower incisor enamel microstructure of the fossil rodent family Eomyidae was believed to be three-layered and highly derived but rather uniform throughout the clade. Here, we describe a new four-layered schmelzmuster in Eomyidae consisting of a three-fold portio interna with longitudinal oriented, uniserial Hunter-Schreger bands and a one-fold portio externa, accounting for a unique enamel microstructure character combination in Rodentia. This new schmelzmuster type has developed early in eomyid evolution and is detectable already in the late Eocene (Chadronian) of North America. In European eomyids, it first occurs in the early Miocene (MN 3), implying that this four-layered schmelzmuster was not present in all members of the family but restricted to species included in Eomyini and some genera currently considered Eomyidae incertae sedis within Eomyidae. Additionally, our analysis recognizes three taxa with schmelzmuster divergent from all other eomyids. Incisor enamel microstructure does not advocate a close phylogenetic relationship of Eomyidae to either fossil or extant Heteromyidae and Geomyidae, nor to fossil Heliscomyidae and Florentiamyidae. Our results rather support the view that Eomyidae are placed outside Geomorpha
Early and Mid-Cretaceous Aristolochiaceous Seeds from Portugal and Eastern North America
No full textPremise of research. The fossil record of Aristolochiaceae (Piperales, magnoliids) is sparse, particularly from Cretaceous strata. Fossil seeds from the Early and mid-Cretaceous of Portugal and North America provide the earliest unequivocal documentation of the group. Methodology. Detailed morphological and anatomical investigations of the fossil aristolochiaceous seeds were carried out using SEM and synchrotron radiation X-ray tomographic microscopy (SRXTM). Comparison with other seeds, extinct as well as extant, was based on published data and SRXTM analyses. Pivotal results. Two new genera and two new species, Aristospermum huberi and Siratospermum mauldinense, are described based on fossil seeds from the Early and mid-Cretaceous of Portugal and North America. The seeds are anatropous and bitegmic, with the micropyle formed by the inner integument. The testa consists of an exotesta of varied thickness and an endotesta of crystalliferous cells. The tegmen is three cell layers thick and consists of an outermost layer of longitudinally aligned fibers, a middle layer of transversely aligned fibers perpendicular to the longitudinal fibers, and an inner layer of thin-walled cuboidal cells. In most seeds the exotesta is abraded, exposing the crystalliferous cells of the endotesta. Among extant plants, a similar seed coat with a crystalliferous endotesta and crossing fibers in the tegmen is unique to Aristolochiaceae. Conclusion. The unique seed coat allows Aristospermum and Siratospermum to be assigned confidently to the lineage that today includes extant Aristolochiaceae. Aristospermum and Siratospermum provide the first unequivocal documentation of the Aristolochiaceae lineage of the Piperales during the Early Cretaceous diversification of angiosperms.We thank the Paul Scherrer Institut, Villigen, Switzerland, for provision of synchrotron radiation beam time at the TOMCAT Beamline X02DA of the Swiss Light Source. We are also grateful to Federica Marone for her help at the Beamline (projects 20141047, 20190071 to P. C. J. Donoghue, S. Bengtson, andE. M. Friis) and Anna Lindström for help with the SRXTM analyses. Support for this researchwas also obtained from the Swedish Research Council (2014-5228 to E.M. Friis) and from the Oak SpringGarden Foundation.</p