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Revisiting the fall of the Veramin meteorite
No full textThe Veramin meteorite, believed to have fallen in 1880, near Varamin, Tehran province, Iran (then Persia), is one of few witnessed falls of a mesosiderite, a rare type of stony-iron meteorite. In this review, it is described that historical records show inconsistencies regarding the fall, and consequently, the naming of the meteorite. The earliest printed account, by Ferdinand Dietzsch in 1881, reported that the meteorite fell near the village “Karand” east of Tehran, with a thunder-like sound. The Shah had ordered an examination of it. Later, meteoricist Aristides Brezina named it "Veramin". Further historical accounts include descriptions by Iranian official Mohammad Hassan Khan Sani’ od-Dowlah and the explorer Sven Hedin. A key document is a Persian text on a cardboard, preserved with the main meteorite mass in Tehran’s Golestan Palace. Members of the nomadic Shahsevan-e Baghdadi tribal confederacy, who had winter settlements west of Tehran, are reported as eyewitnesses. The geologist Henry A. Ward provided a detailed description in 1901, confirming the meteorite's composition and securing a larger mass for analysis and distribution to museums. The exact location and date of the fall remain uncertain due to imprecise and conflicting sources. The most likely impact field is the Booghin-Eshtehard area west of Tehran, with the event happening sometime in the period February to April 1880. The original mentioning of “Karand” is a confusion with Zarand(ieh), 70 km to the west of Varamin
Too Far From Relatives? Impact of the Genetic Distance on the Success of Exon Capture in Phylogenomics
No full textWhen did spotted hyenas become social? Evidence from fossil endocasts
No full textThe spotted hyena, Crocuta crocuta, is a highly social carnivore with several unique traits showing advanced social behavior. Studies of the brain of living spotted hyenas show that the anterior cerebrum is enlarged, a feature linked to sociality. It is not known, however, when sociality evolved in spotted hyenas, and its evolutionary context is therefore unknown. This is important to understand due to the apparent negative fitness effects of some spotted hyena traits. Studies of extinct species of Crocuta have shown that these do not share the large anterior cerebrum of the extant species. We use computed tomography (CT) scanning to study the endocranium of a >350,000-year-old spotted hyena from Megenta, Ethiopia and compare it to a sample of modern specimens representing the four living Hyaenidae species. We also compared our results to published fossil hyena endocrania. We found that the brain of the Ethiopian fossil is indistinguishable from that of the extant species and different from all other fossil and extant hyena brains. This places a minimum age of 350,000 years on the evolution of spotted hyena sociality and eliminates factors such as selective pressure from early Homo sapiens as potential drivers of sociality
Combining Individual‐Based Radio‐Tracking With Whole‐Genome Sequencing Data Reveals Candidate for Genetic Basis of Partial Migration in a Songbird
No full text Partial migration is a phenomenon where migratory and resident individuals of the same species co-exist within a population, and has been linked to both intrinsic (e.g., genetic) as well as environmental factors. Here we investigated the genomic architecture of partial migration in the common blackbird, a songbird that comprises resident populations in the southern distribution range, partial migratory populations in central Europe, and exclusively migratory populations in northern and eastern Europe. We generated whole-genome sequencing data for 60 individuals, each of which was phenotyped for migratory behavior using radio-telemetry tracking. These individuals were sampled across the species' distribution range, including resident populations (Spain and France), obligate migrants (Russia), and a partial migratory population with equal numbers of migratory and resident individuals in Germany. We estimated genetic differentiation (FST) of single-nucleotide variants (SNVs) in 2.5 kb windows between all possible population and migratory phenotype combinations, and focused our characterization on birds from the partial migratory population in Germany. Despite overall low differentiation within the partial migratory German population, we identified several outlier regions with elevated differentiation on four distinct chromosomes. The region with the highest relative and absolute differentiation was located on chromosome 9, overlapping PER2, which has previously been shown to be involved in the control of the circadian rhythm across vertebrates. While this region showed high levels of differentiation, no fixed variant could be identified, supporting the notion that a complex phenotype such as migratory behavior is likely controlled by a large number of genetic loci
Fossil leaf cuticle: Best practices for preparation and paleo-CO2 analysis
No full text Leaf cuticle is the waxy envelope that protects leaves from desiccation, UV damage, and abrasion. The cuticle encodes information about a plant's chemistry and leaf epidermal and stomatal cell morphology. Fossil leaf cuticle has been used to determine taxonomic affinities for almost two centuries and recognized in recent decades for its value in reconstructing paleoenvironments and paleoclimates, especially atmospheric CO2. Fossil leaf cuticle preparation techniques are typically reported as single workflows tied to individual studies, starting with finding fossils in the field through the steps of preparing cuticle for chemical and morphological analysis, including decisions about type of microscopy and level of sampling effort at different spatial scales (number of fields-of-view, leaves, and species). The siloed nature of these publications makes finding appropriate methods and workflows for new studies difficult, especially for less experienced researchers. Here, we attempt to synthesize a breadth of existing workflows and make recommendations to guide methodological decision-making for new studies, with a particular focus on paleo-CO2 reconstruction via a proxy based on leaf gas-exchange principles (the Franks model). We describe and annotate chemical procedures for preparing cuticles for analysis and include recommendations regarding leaf conditions for which each is most appropriate. For studies making repeated measures of morphology (e.g., stomatal density), we describe a resampling routine that can guide decision-making, in real time, about sampling effort.This project was conceived at workshops associated with the CO2 Proxy Integration Project (CO2PIP). Funding comes from National Science Foundation of USA (grant number FRES 2121540 to DLR and grant number FRES 2121594 to IPM), the National Natural Science Foundation of China (grant number NSFC 42202024 to XZ), and Natural Science Foundation of Jiangsu Province, China (grant number BK20221160 to XZ).</p
New insights into two poorly known monogeneans (Platyhelminthes), gill parasites of the European barracuda Sphyraena sphyraena (Teleostei, Sphyraenidae) with notes on Chauhanea Ramalingam, 1953 and closely related genera
No full textTwo poorly known parasitic Platyhelminthes were collected from the gills of the European barracuda Sphyraena sphyraena in the western Mediterranean. Specimens of Chauhanea mediterranea Euzet & Trilles, 1960 and Rhinecotyle crepitacula Euzet & Trilles, 1960 (Polyopisthocotyla) are redescribed based on newly collected material. A careful examination of Ch. mediterranea revealed inaccuracies in previous interpretations of the female openings. The midventral opening, previously referred to as the ‘vaginal opening’ in Pseudochauhanea Yamaguti, 1965 and used to distinguish this genus from Chauhanea Ramalingam, 1953, is demonstrated to be the uterus, as confirmed by the presence of eggs in the thin-walled duct associated with this opening. The lateral position of the cirrus and vagina is also confirmed. Consequently, Pseudochauhanea is synonymized with Chauhanea, resulting in the following new combinations: Ch. elegans Fuentes-Zambrano, 1997 n. comb.; Ch. elongata Kritsky, Bilqees & Leiby, 1972 n. comb.; Ch. macrorchis Lin, Liu & Zhang in Zhang, Yang & Liu, 2001 n. comb.; Ch. mexicana Lamothe, 1967 n. comb.; Ch. sphyraenae Yamaguti, 1965 n. comb. A detailed investigation of the clamp sclerites of Ch. mediterranea indicates that both Chauhanea and Cotyloatlantica Bravo-Hollis, 1984 share the subdivision of the basal oblique sclerite, which is a continuation of the marginal sclerite in the anterior jaw, a key feature used to distinguish these genera. As a result, Cotyloatlantica is also synonymized with Chauhanea, and its species are transferred as follows: Ch. pretiosa (Bravo-Hollis, 1984) n. comb. The reinstatement of Ch. mediterranea Euzet & Trilles, 1960 as a valid name is supported, and an amended diagnosis of Chauhanea is provided. Additionally, R. crepitacula is accurately redescribed, with a new geographical locality record and an assessment of morphometrical and anatomical variations between Mediterranean and oceanic specimens.Systematics and integrative taxonomy of Monogenea parasitizing fishes of Swede
A closer look at the Choricotyle chrysophryi-like (Polyopisthocotyla: Diclidophoridae) species complex: description of a new Choricotyle from the gills of Pagellus acarne (Teleostei: Sparidae) and revision of Choricotyle spp. from sparids
No full textPurpose: The genus Choricotyle, the largest in the diclidophoridean family, includes C. chrysophryi, whose taxonomic status remains ambiguous. This study aims to resolve this ambiguity by describing a new Choricotyle species, C. justinemusei n. sp. previously identified as C. cf. chrysophryi, and clarifying the taxonomic status of related congeneric species, particularly those reported from sparids in Mediterranean and Atlantic waters. Methods: Choricotyle justinemusei n. sp. was described based on Mediterranean specimens from the gills of Pagellus acarne, found in the Muséum National d'Histoire Naturelle, Paris. The species was differentiated from its congeners through morphological and anatomical features, including the presence or absence of a terminal lappet, and of ring organ, number of atrial hooks and of testes. Molecular analysis using cox1 sequences was also conducted to aid in species identification. Results: Choricotyle justinemusei n. sp. was described and distinguished from other Choricotyle species by several key morphological traits and molecular sequences. The record of C. chrysophryi from Pagellus bogaraveo in Atlantic waters was reassigned to C. chrysophryi sensu Llewellyn (1941). Furthermore, C. pagelli from P. bogaraveo was found to be distinct from C. chrysophryi sensu Llewellyn (1941), confirming the validity of both C. pagelli and C. chrysophryi as separate species, and the former was reinstated as a valid species. A differential diagnosis was also provided for C. marionis, reinstating it based on its original type-host, Spicara maena. Conclusion: This study clarifies the taxonomic status of C. chrysophryi and related species, describing C. justinemusei n. sp. and reinstating C. pagelli and C. marionis as valid species. These findings contribute to a more accurate understanding of Choricotyle species and their host specificity.Systematics and integrative taxonomy of Monogenea parasitizing fishes of Swede
Insights into garnet growth in S-type granite from Lu–Hf dating and trace element mapping
No full textGarnet is a common minor phase in S-type granites and pegmatites, but its petrogenesis remains poorly constrained. Gar-net in these systems may have crystallized from the melt or it may represent inherited grains derived from the source orxenocrysts from the wall rocks. Although garnet has the potential to provide unique insights into the magmatic evolutionand crystallization intervals of S-type granites and pegmatites, its geochemical and chronological record is underexplored.In this study, we investigate the Lu–Hf age and trace-element record of garnet in the Neoarchean Decelles Batholith(c. 2670–2620 Ma), southeastern Superior Craton, Canada. The batholith comprises one of the most voluminous gran-ites in the region and was likely sourced from anatexis of the metasedimentary Pontiac Group at depth. Garnet Lu–Hfgeochronology yielded ages between 2667.5 ± 3.9 and 2656.0 ± 7.1 Ma, overlapping with U–Pb monazite ages from thebatholith and Lu–Hf ages from the host rocks. LA-ICP-MS trace-element mapping revealed well-preserved sharp oscil-latory—locally sector—zoning in Li, P, Sc, Ti, Y, Zr, REE, Hf, Th, and U, contrasting with weak major element zoning.Garnet grains exhibit a core with concentric zoning and an overgrowth domain truncating core patterns, reflecting bothtrace-element uptake controlled by varying crystal growth rates, element supply and diffusion at the garnet-matrix interfacein the presence of melt, and cation supply limitations due to co-crystallization of muscovite, monazite, apatite, and zircon.The data support a magmatic origin for garnet in the peraluminous granite and demonstrate that the oscillatory zoning canbe diagnostic. Moreover, the new Lu–Hf garnet dates place new constraints on the timing of crystallization of the DecellesBatholith. This study provides new insights into the conditions of garnet crystallization in granitic systems and illustratesthe versatility of garnet in constraining the onset and later evolution of peraluminous granitoid magmatism. Ultimately, ourstudy underscores the necessity of case-by-case assessment of garnet origins in S-type granites, emphasizing trace-elementmapping as a key tool for petrogenetic interpretation
Genome Skimming of Thysanoptera (Arthropoda, Insecta) and Its Taxonomic and Systematic Applications
No full textHigh-throughput sequencing has transformed molecular systematics. This study presents a semi-automated pipeline for genome skimming in Thysanoptera, an insect order known for challenging species identification and cryptic relationships. By efficiently obtaining mitochondrial genomes and nuclear genes from multiple thrips specimens, the study evaluates the limitations of traditional barcoding and the data required for accurate species delimitation. The results highlight the importance of the sequencing data volume and this pipeline in reconstructing Thysanoptera phylogeny. This research also showcases the potential of advanced sequencing techniques for species delimitation and phylogenetics