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GENUS BYRSAX PASCOE, 1860(COLEOPTERA: TENEBRIONIDAE) IN THE SOLOMON ISLANDS AND NEW GUINEA WITH DESCRIPTION OF A NEW SPECIES
Get PDFNew faunistic, country and biogeographical records are provided for Byrsax biroi Kaszab, 1939 and B. pinnaticollis Carter, 1914. Byrsax crypticus sp. nov. from the Solomon Islands is described and illustrated. Morphological features of the Papuan representatives of the genus Byrsax are briefly discussed.The attached file is the published version of the article.NHM Repositor
Lineage Thinking in Evolutionary Biology: How to Improve the Teaching of Tree Thinking
Get PDFAbstract - In 1988, Robert O’Hara coined the now ubiquitous phrase “tree thinking” to highlight the importance of cladistics for proper evolutionary reasoning. This accessible phrase has been taken up widely in the professional, popular, and educational literatures, and it has played an important role in helping spread phylogenetic thinking far beyond the disciplinary borders of systematics. However, the undeniable benefits of the spread of tree thinking have become marred by being widely linked to several misconceptions that were present in O’Hara’s original writings. O’Hara incorrectly considered clades to be the central subjects of evolutionary narratives. By failing to appreciate that clades contain independently evolving lineages, O’Hara has promoted the misleading view that evolution is irreducibly branched. In this paper, I show how an exclusive focus on the branching realm of taxa has created a cladistic blindfold that has caused a form of lineage blindness that has spread widely through the literature dedicated to the teaching of tree thinking. Its symptoms include the rejection of phenomena and concepts that are fundamental to the realm of evolving lineages, including linear evolutionary imagery and narratives, the concepts of anagenetic evolution and missing links, our evolutionary descent from monkeys and apes, and the promotion of the nonsensical concept of collateral ancestors. To avoid simplistic tree thinking, it is crucial to recognize that the realms of taxa and lineages have distinctive features that require different kinds of thinking. I close by suggesting that teaching can be improved by linking tree thinking explicitly to lineage thinking.Copyright © The Author(s) 2024. The attached file is the published version of the article.NHM Repositor
The Pupal Pigmentation Pattern and Pupal Development in the Species of Aphytis Howard (Hymenoptera: Aphelinidae)
Get PDFSpecies identification of Aphytis on the basis of adult morphology is extremely difficult, especially in the A. lingnanensis group, with several cryptic species. Pupal pigmentation could be used as one of the taxonomic characters for Aphytis species, and in some instances, pupal pigmentation actually provided the first clue to the distinctness of cryptic Aphytis species. The present study investigated the full-grown larvae or younger pupae of Aphytis species, and pupal pigmentation and pupal development were observed and photographed. Four characteristic pigmentation patterns of Aphytis pupae were summarized including: entirely yellow, partly dark brown, entirely or predominantly black, and partly black. The species in the chilensis and mytilaspidis groups, and some unassigned species, generally have entirely, or predominantly and or partly black pupae. The species in the chrysomphali, funicularis, and proclia groups generally have the pupae entirely yellow. The species of the lingnanensis group have the pupae both entirely yellow, e.g., A. fisheri, and partly dark brown pupae, e.g., A. lingnanensis, A. holoxanthus and A. melinus. The pupae of Aphytis species in this study had a developmental duration of about 5–8 days at 27 ± 1 °C, 70 ± 5% RH and a photoperiod of 10L: 14D. It was found that the pupal skin was always melanized at the beginning stage, generally in the first day, among the pigmented pupae of Aphytis species. As development continued, the pigmentation became darker and the eye colour changed from pale red/brown to green. No significant intra-specific variation in pupal colour pattern was detected despite relatively high numbers of specimens examined, many from multiple, and different, origins. Overall, our study indicates that pupal pigmentation could be more helpful in species identification of Aphytis.Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). The attached file is the published version of the article.NHM Repositor
Detection and Quantification of Extraterrestrial Platinum Group Element Alloy Micronuggets from Archean Impactite Deposits by Low-Voltage Scanning Electron Microscopy/Energy-Dispersive X-ray Spectrometry
No full textAbstract
Rare, heterogeneously composed platinum group element alloy micronuggets (PGNs) occur in primitive meteorites, micrometeorites, and terrestrial impactite deposits. To gain insight into the nature of these phases, we developed a workflow for the characterization of PGNs using modern scanning electron microscopy (SEM) and energy-dispersive X-ray spectrometry at a low accelerating voltage of 6 kV. Automated feature analysis—a combination of morphological image analysis and elemental analysis with stage control—allowed us to detect PGNs down to 200 nm over a relatively large analysis area of 53 mm2 with a conventional silicon drift detector (SDD). Hyperspectral imaging with a high-sensitivity, annular SDD can be performed at low beam current (∼100 pA) which improves the SEM image resolution and minimizes hydrocarbon contamination. The severe overlapping peaks of the platinum group element L and M line families at 2–3 keV and the Fe and Ni L line families at <1 keV can be resolved by peak deconvolution. Quantitative elemental analysis can be performed at a spatial resolution of <80 nm; however, the results are affected by background subtraction errors for the Fe L line family. Furthermore, the inaccuracy of the matrix correction coefficients may influence standards-based quantification with pure element reference samples.Copyright © The Author(s) 2023. Published by Oxford University Press on behalf of the Microscopy Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.NHM Repositor
Effect of Different Constant Temperatures on Life History and Life Table Parameters of Trichogramma euproctidis (Hymenoptera: Trichogrammatidae)
Get PDFAbstract: Temperature has a profound effect on performance and behavior of egg parasitoids. Egg parasitoids are a well-known alternative for the control of lepidopterous pests. Selected life history parameters of Trichogramma euproctidis (Girault) (Hymenoptera: Trichogrammatidae), an established egg parasitoid species in Khuzestan- Southwest Iran, were appraised at eight constant temperatures (22.5, 25, 27.5, 30, 32.5, 35, 37.5, and 40°C) using Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) eggs as the host. We found significant effects of temperature on the number of parasitized eggs, development time, sex ratio, progeny’s longevity, and fecundity. T. euproctidis developed on E. kuehniella eggs at all temperatures tested, but performed best at 32.5°C. At this temperature, they parasitized the most eggs, produced the most female progeny, and had high rates of survival. Our findings revealed that temperature significantly affected the longevity of female progeny and fecundity of T. euproctidis. A life table analysis confirmed that temperature resulted in optimal effects on T. euproctidis life history. Net reproductive rate (R0) of T. euproctidis was different among the temperatures tested. The intrinsic rate of increase (r) was positively correlated with temperature from 22.5 to 32.5°C and then decreased from 35 to 40°C. Generation time (T) and doubling time (DT) decreased as temperature increased from 22.5 to 37.5°C and then increased at 40°C. These data suggest that this strain of T. euproctidis is adapted to high temperatures and harsh environmental conditions and has the potential to be used in integrated management programs in Southwest Iran.Copyright © The Author(s) 2022. Published by Oxford University Press on behalf of Entomological Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial License (https://creativecommons.org/ licenses/by-nc/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact [email protected] Repositor
The Carboniferous (Serpukhovian) macroflora from the “Coteaux du Pont Barré”, Beaulieu-sur-Layon (Maine-et-Loire), South of the Armorican Massif, France
No full textThe “Coteaux du Pont Barré” in Beaulieu-sur-Layon is a Regional Natural Reserve which is home to exceptional flora and fauna. Recently fossil plants have been discovered at the site adding to its natural heritage significance. The exposure which is part of the “Sillon Houiller de la Basse-Loire” contains Serpukhovian-age (330–320 Ma) remains of sphenophytes, ferns, and lyginopteridopsid and cycadopsid pteridosperms, which are described for the first time as well as the geology of the site. Most Carboniferous macroflora previously described from the Maine-et-Loire has been based on ex situ specimens from now abandoned and inaccessible coal mines. The newly described macroflora shows evidence of in situ remains and differs somewhat in composition from those reported from the coal workings, especially in the total absence of lycopsids and Calymmotheca pteridosperms, and instead having abundant medullosalean foliage (Neuralethopteris). The co-occurrence of Sphenopteris elegans and Neuralethopteris densifolia suggests a slightly younger age compared to the macrofloras documented from the coal-bearing deposits. However, this could be an ecological consequence of the flora growing in better-drained substrate habitats.Copyright © 2023 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.
This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License (http://creativecommons.org/licenses/bync-nd/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way. The linked document is the published version of the article.NHM Repositor
A new interpretation of Pikaia reveals the origins of the chordate body plan
No full textOur understanding of the evolutionary origin of Chordata, one of the most disparate and ecologically significant animal phyla, is hindered by a lack of unambiguous stem-group relatives. Problematic Cambrian fossils that have been considered as candidate chordates include vetulicolians (1) Yunnanozoon (2) and the iconic Pikaia (3) However, their phylogenetic placement has remained poorly constrained, impeding reconstructions of character evolution along the chordate stem lineage. Here we reinterpret the morphology of Pikaia, providing evidence for a gut canal and, crucially, a dorsal nerve cord—a robust chordate synapomorphy. The identification of these structures underpins a new anatomical model of Pikaia that shows that this fossil was previously interpreted upside down.We reveal a myomere configuration intermediate between amphioxus and vertebrates and establish morphological links between Yunnanozoon, Pikaia, and uncontroversial chordates. In this light, we perform a new phylogenetic analysis, using a revised, comprehensive deuterostome dataset, and establish a chordate stem lineage. We resolve vetulicolians as a paraphyletic group comprising the earliest diverging stem chordates, subtending a grade of more derived stem-group chordates comprising Yunnanozoon and Pikaia. Our phylogenetic results reveal the stepwise acquisition of characters diagnostic of the chordate crown group. In addition, they chart a phase in early chordate evolution defined by the gradual integration of the pharyngeal region with a segmented axial musculature, supporting classical evolutionary-developmental hypotheses of chordate origins4 and revealing a ‘‘lost chapter’’ in the history of the phylum.Copyright © 2024 Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). The linked document is the published version of the article.NHM Repositor
Notes on some Greek Microhoria Chevrolat, 1877 (Insecta: Coleoptera: Anthicidae) with new descriptions and synonymy
Get PDFTaxonomic changes, new records and descriptions of Microhoria Chevrolat, 1877 from Greece are presented. Microhoria emgei (Pic, 1897) statt. restit. is removed from synonymy with M. terminata (W.L.E. Schmidt, 1842) and considered valid species. The following five species new to science are described and illustrated: Microhoria berrai, M. mammuthus, M. melecisi, M. sabellai, and M. vetroveci spp. nov., all from Crete. Lectotype designation is made for M. funeraria (Marseul, 1879) to maintain nomenclatural stability. The following new synonyms are introduced: Microhoria basithorax (Pic, 1941) = M. cerrutii Bucciarelli, 1976 syn. nov., M. fasciata fasciata (Chevrolat, 1834) = M. caliginosa pannonica (Kaszab, 1956a) syn. nov., M. pinicola (Reitter, 1889) = Anthicus terminatus var. latebrunneus Pic, 1901 syn. nov. (hitherto considered a synonym of M. terminata), M. unicolor (W.L.E. Schmidt, 1842) = M. unicolor calliger (Marseul, 1879) syn. nov., = M. sydowi sydowi (Pic, 1936) syn. nov., = M. sydowi reductior (Pic, 1936) syn. nov., = M. sydowi olympiae (Pic, 1941) syn. nov. Supplementary descriptions of eight poorly known species of Microhoria are made. An erroneous species-concept is corrected for M. raveli (Pic, 1899). Several new faunistic records and ecological observations are provided for poorly known species. Additionally, a new synonym is introduced for non-Greek taxa, M. akbesiana (Pic, 1896) = M. fasciata helvetica (Krekich-Strassoldo, 1929) syn. nov.The attached file is the published version of the article.NHM Repositor
Post-cratering melting of target rocks at the impact melt contact: Observations from the Vredefort impact structure, South Africa
No full textImpact melt is generated following hypervelocity impact events. Emplacement of impact melt dikes, such as the Vredefort Granophyre Dikes, allow for this high temperature melt to come into contact with deeply-buried target rocks after the cratering process is completed. Our study analyzes the effects of this interaction by examining the direct contact between the Vredefort Granophyre and the granitic host at the Kopjeskraal and Lesutoskraal Granophyre Dikes using scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), electron backscatter diffraction (EBSD), and X-ray micro-computed tomography (μCT). A several-mm-thick transition zone between the host rock and the impact melt is enriched in SiO2 and indicates preferential melting of feldspar and mica in the host rock by interaction with the impact melt. Immiscible droplets of newly-formed silicate melt migrated from the transition zone into the impact melt. We observe inundations of the impact melt along narrow fractures into the host rocks, which, in some cases, surround and incorporate fragments of the host rock into the melt body. We suggest three possible mechanisms by which components of the host rock can enter the impact melt: 1) fragmentation of the host rock prior to melt emplacement and subsequent entrainment into the melt; 2) inundations of melt around fragments of host rock at the contact, followed by incorporation of the host rock into the melt; 3) melting of the host rock and immiscible migration of melt fragments within the impact melt. The lack of observed assimilation of the granitic fragments into the impact melt, either because of silica saturation or viscosity contrast between the melts, suggests that the bulk composition of the Granophyre Dike matrix approximately represents the composition of the impact melt sheet.Copyright © 2024 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/). The linked file is the published version of the article.NHM Repositor
The Winchcombe meteorite, a unique and pristine witness from the outer solar system
No full textDirect links between carbonaceous chondrites and their parent bodies in the solar system are rare. The Winchcombe meteorite is the most accurately recorded carbonaceous chondrite fall. Its pre-atmospheric orbit and cosmic-ray exposure age confirm that it arrived on Earth shortly after ejection from a primitive asteroid. Recovered only hours after falling, the composition of the Winchcombe meteorite is largely unmodified by the terrestrial environment. It contains abundant hydrated silicates formed during fluid-rock reactions, and carbon- and nitrogen-bearing organic matter including soluble protein amino acids. The near-pristine hydrogen isotopic composition of the Winchcombe meteorite is comparable to the terrestrial hydrosphere, providing further evidence that volatile-rich carbonaceous asteroids played an important role in the origin of Earth’s water.Copyright © 2022 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution License 4.0 (CC BY). The linked file is the published version of the article.NHM Repositor