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A model for groundwater silicification within the Sables de Fontainebleau in sub-contemporary landscapes in the Paris Basin proposed 35 years ago has since been continuously and substantially updated, particularly with reference to new studies that relate silica precipitation to periglacial climate conditions. Herein we link the various distinctive morphologies of silicified sandstone bodies to the flow paths of groundwaters that imported the silica, the conditions under which it was precipitated, and the patterns of iced ground. The silicified masses are, in a way, fossil groundwater flow paths. The spatial arrangements of these paleo-groundwater flow paths suggest that permafrost developed to significant depth in parts of the Paris Basin. Our model visualizes a gradual settlement of periglacial conditions in the landscape starting with (1) cooling of the near-surface regolith and development of horizontal silicified pans; (2) progressive descent of impermeable permafrost as glacial conditions persisted, leading to non-horizontal flows ‘forced’ beneath the frozen layer; (3) thickening of the permafrost and consequent pressurization of groundwater in the phreatic zone when groundwater outflows to the valleys froze and closed, and convoluted silicified masses and possibly vertical dikes were formed; (4) followed by later thawing of the permafrost and a reduction in hydrostatic level due to climate warming leading to growth of geotropic silicified bodies when residual permafrost remained at depth. In this context, the distinctive morphologies of the silicified sand masses are proxies for the paleohydrology that prevailed during silicification and constitute a new toolbox for determining the depths reached by permafrost at time of silicification.
The East Asian region has seen the first discovery of trematodes of the genus Psilotrema in the muskrat Ondatra zibethicus. When studying the morphology of the trematodes, two morphotypes were identified among individuals of Psilotrema spp., the differences between which at the morphological level are equivalent to those between species. The affiliation of one of these morphotypes with the bird parasite Psilotrema limosum was established based on partial sequences of genes coding for 28S ribosomal RNA, nad1, and cox1 mitochondrial DNA. Based on the analysis of these three markers, we classified individuals with this morphotype as P. limosum, despite some morphological features of worms infecting birds. At the same time, the worms with second morphotype had no interspecies differences based on the first two markers, while the cox1 gene confirmed the separation of these samples on a species level. These trematodes were described as a new species, Psilotrema elegans n. sp., based on both morphological and molecular data.
The present study describes a new Mediterranean terebellid, Spinosphaera latachaeta sp. nov., found along the Aegean coast of Türkiye and the Sea of Marmara, between 27 and 80 m depth in soft substrata. It can be morphologically distinguished from all other species of Spinosphaera having 18 pairs of notopodia, double rows of uncini present until the last notopodia, and 11 pairs of Spinosphaera-chaetae. A dichotomous taxonomic key and a table summarizing the morphological characters that distinguish all species of Spinosphaera are provided. This study also reports, for the first time, the transformations of Spinosphaera-chaetae and saw-like chaetae from the anterior to posterior segments of body.
Understanding complex three-dimensional cardiac structures is the key to knowing CHD. Many learners have limited access to cadaveric specimens, and most alternative teaching modalities are two-dimensional. Therefore, we have developed virtual cardiac models using photogrammetry of actual heart specimens to address this educational need.
Methods:
A descriptive study was conducted at a single institution during a week-long cardiac morphology conference in October 2022 and 2023. Conference attendees viewed virtual cardiac models via laptop screen and virtual reality headset. Learners were surveyed on their opinions of the virtual models and their perceived effectiveness compared to existing educational materials.
Results:
Forty-six learners completed the survey. Participants reported the virtual cardiac models to be more effective than textbook diagrams (60%), and equally or more effective compared to didactic teaching (78%) and specimen videos (78%). Approximately half of participants (54%) found the virtual models to be less effective than hands-on cadaveric specimen inspection. Attitudes towards the virtual specimens were overall positive with most responders finding the tool engaging (87%) and enjoyable (85%). A majority reported that the models deepened their understanding of cardiac morphology (79%) and that they would recommend them to other trainees (87%).
Conclusions:
This study demonstrates that a novel teaching tool, virtual cardiac specimens, is equivalent to or more effective than many current materials for learning cardiac morphology. While they may not replace direct cadaveric specimen review, virtual models are an engaging alternative with the ability to reach a wider audience.
This paper focuses on two phenomena in Irish agreement – namely, complementarity between overt in-situ arguments and agreement, and the obviation of this complementarity under A-movement. An analysis of these facts is offered in terms of the defective goal ‘incorporation’ (DGI) mechanism proposed by Roberts (2010), and applied to cases of complementarity in Bantu languages by Iorio (2014), and van der Wal (2015, 2020, 2022), as well as asymmetric chains under A-movement, consisting of a full copy and a pronominal $ \phi $-feature bundle; cf. similar configurations discussed by Takahashi & Hulsey (2009), Harizanov (2014), Kramer (2014), Baker & Kramer (2018), inter alios. It is shown that this approach accounts for the facts in Irish and that the same account can be extended to explain facts concerning participial agreement in, for example, Italian. Additional cross-linguistic implications are also considered, particularly with respect to French and Welsh.
Equids are infected by a diversity of gastrointestinal nematode parasites, including 64 species of equine strongyle nematodes from19 genera. Despite numerous surveys of horse strongyles worldwide, certain geographic regions and rare species remain understudied. In 1964, a new species of equine strongyle, Cylicocyclus pekingensis, was described from a donkey in China. Subsequently, this species was recorded in horses from Kazakhstan and reclassified as Hsiungia pekingensis (K’ung and Yang, 1964), the only species in this genus. Since then, H. pekingensis has not been reported elsewhere, with limited knowledge on its distribution and phylogeny.
This study documents the first record of H. pekingensis in North America. Adult specimens were recovered from fecal samples of a domestic horse in Alberta, Canada, following treatment with ivermectin. Species identification involved detailed morphological examination, complemented with sequencing of the internal transcribed spacer 1 (ITS1), 5.8S rRNA gene, and the internal transcribed spacer 2 (ITS2) regions of the nuclear genome. Phylogenetic analysis indicated a close evolutionary relationship with species from Poteriostomum and Parapoteriostomum genera. Nemabiome ITS2 sequencing of a paired pre-treatment sample also detected the presence of H. pekingensis in the studied horse. Re-analysis of public equine nemabiome datasets further detected H. pekingensis in feral horses in Alberta, but not in other regions considered. This study expands the known distribution of this rare species and enhances our knowledge of its placement in the phylogeny of equine strongyles. Furthermore, our re-analysis of public nemabiome datasets highlights the value of this approach for studying the global distribution of parasite species.
Inflectional systems vary along multiple dimensions (number of members, size of paradigms, word class, integrative complexity, accidents of history, etc.). This makes it difficult to find significant correlations and causality relations between different properties, as attested systems usually differ in multiple ways at the same time, thus obscuring possible relations between individual variables. Here we analyze the relation between a system’s size by number of members and its morphological complexity. We do so by exploring in detail, via quantitative methods, the cognate inflectional systems of Central Pame and Chichimec (Otomanguean, Mexico), whose inflecting nominal classes differ precisely mostly with regard to their size (i.e. number of members).
The parasites of Nile tilapia, Oreochromis niloticus (Linnaeus, 1758) are poorly documented in the United States despite the economic importance and global introduction of this African fish. Only one metazoan parasite (Gyrodactylus cichlidarum Paperna, 1968; Gyrodactylidae) reportedly infects Nile tilapia in the United States. Examining Nile tilapia from a flow-through aquaculture system hydrologically linked to Sougahatchee Creek (Tallapoosa River, Auburn, Alabama), we observed a gill infection by Cichlidogyrus sclerosus Paperna & Thurston, 1969 (Dactylogyridae). This monogenoid was originally described from the gill of Mozambique tilapia, Oreochromis mossambicus (Peters, 1852) from Lake Victoria, Uganda. Specimens of C. sclerosus were studied for morphology and phylogenetic analyses using the 28S and ITS1. We identified our specimens as C. sclerosus because they had the following combination of morphological features: marginal hooks shorter than dorsal anchor length; anchor roots reduced; dorsal anchor point bent; dorsal bar pyriform projections approximately half as long as dorsal bar width; penis short (<100 μm), not coiled, tubular, lacking swelling, having irregularly surfaced heel; and accessory piece straight and bifid. Our 28S and ITS1 phylogenies recovered our C. sclerosus sequences in a clade with conspecific sequences and showed no obvious biogeographic pattern. Cichlidogyrus sclerosus reportedly infects 21 fishes of 11 genera and 3 families from 36 countries in Africa, Asia, North America, South America, and Europe. The study of Nile tilapia parasites, especially those exhibiting direct life cycles and low host specificity, is important because they comprise potential invasive species.
A new lungworm species, Serpentirhabdias orientalis sp. nov., was discovered in the respiratory organs of the monocled cobra (Naja kaouthia) in Thailand, marking the first record of a Serpentirhabdias species in both the Oriental Region – Southeast Asia – and in an elapid snake. Morphological analysis revealed distinctive features that clearly differentiate it from all 22 previously known species, such as an elongated body (up to 5858 µm), 6 onchia, a triangular oral opening, and a thin cuticle. The species also exhibited significant differences in several characteristics, such as tail length, distance from the anterior end to the excretory pore and the number of eggs in the uteri, when compared to closely related species such as Serpentirhabdias moi and Serpentirhabdias mussuranae. Specimens were analysed using light microscopy, and genetic sequencing of COI and 28S rRNA confirmed its distinctiveness. Phylogenetic analysis, reinforced by morphological data, revealed a close relationship between S. orientalis sp. nov. and Neotropical species, raising intriguing questions about the biogeography and evolutionary history of lungworms. The high prevalence and intensity of infection in the monocled cobras could have ecological consequences, potentially impacting the health of wild snake populations. Increasing wildlife–human interactions highlight the need to monitor parasitic infections for ecological and veterinary insights. These findings contribute to the expanding taxonomy of Serpentirhabdias and emphasize the importance of further research into parasitic infections in both wild and captive reptiles, with potential implications for conservation and veterinary management.
This study on distribution of Ophiothrix savignyi was carried out from 2017 to 2022 in the Iranian waters of the Persian Gulf. Nineteen locations were sampled from coastal waters, including 16 newly reported areas. O. savignyi was epizoic, associated mostly with sponges, sea urchins, and soft corals. This survey shows O. savignyi as the most common and widespread brittle star in the northern and eastern Persian Gulf. In this study, O. savignyi, has been described again from the Persian Gulf.
The framework of Construction Grammar extends naturally to morphology. Constructions in a lexicon–grammar continuum elegantly capture the regularities and idiosyncrasies that typically co-occur in complex words. Yet, Construction Morphology is not just Construction Grammar applied to morphology. Morphological phenomena come with their own challenges and place specific demands on the theory. This chapter outlines the contributions that a constructionist approach to morphology makes to constructionist thinking more broadly. The focus is on two construction-based approaches: Construction Morphology and Relational Morphology. Three topics are highlighted especially. First, idiomaticity and other types of non-compositionality are discussed in the context of the relations within and across morphological constructions. Second, the chapter addresses productivity, specifically limited productivity as is often seen in word-formation. The third topic is paradigmaticity and the role of ‘horizontal’ connections between complex words and between morphological schemas. The chapter aims to show that morphology, the grammar of words, is instructive for the larger theoretical framework.
Morphological and molecular methods were used to describe a new species of Trapania Pruvot-Fol, 1931 from shallow water kelp forests on the north-central coast of Peru. The new species, Trapania huarmeyana sp. nov., is distinguished from other species along the Eastern Pacific by external morphological characters such as its translucent white body with brown stripes and small spots on the dorsum, blotches on the base of the extra-branchial processes, extra rhinophoral processes and gill branches. Internally, T. huarmeyana sp. nov. is distinguishable by several morphological characteristics of the radula, jaws and genital organs. Phylogenetic trees recovered using Bayesian Inference and Maximum Likelihood analysis of DNA sequences support its distinct status and clarify its relationship to other species from the Eastern Pacific. This new species constitutes the first record of Trapania from the Humboldt Current Ecosystem, contributing to our understanding of the distribution of the genus in the South-eastern Pacific.
While the giant anemone, Relicanthus daphneae, has been described as a characteristic inhabitant of the East Pacific Ocean since 1991, there are relatively few published occurrences worldwide. Here, we present the discovery and molecular verification of R. daphneae along the southern Central Indian Ridge, at the Rodriguez Triple Junction, and along the northern Southeast Indian Ridge within the BGR contract area for the exploration of marine massive sulphide deposits in the Indian Ocean. Individuals were solitary and attached exclusively to basalt hard substrates on the periphery of hydrothermal vent fields, at distances from active vents between 66 and 710 m. We report megafauna observed in close proximity to R. daphneae and, in one case, polychaetes on its tentacles and oral disc. For the first time, the giant anemone was observed capturing prey, a shrimp of the species Rimicaris kairei. Beyond this remark on the diet of these anemones, we also report other behavioural aspects for this species.
A new species of Heligmostrongylus (Nematoda: Heligmonellidae) is described from the small rodents Ototylomys phyllotis (Cricetidae: Tylomyinae) and Heteromys gaumeri (Heteromyidae: Heteromyinae) in the Yucatan Peninsula, Mexico, based on studies of light and scanning electron microscopy, and partial sequences of COI, ITS1 and 28S rRNA. Heligmostrongylus yucatanensis n. sp. is characterized by a synlophe of 13 interrupted ridges (except those forming careen) in both sexes at midbody; males with a ventral cuticle inflation at anterior region of copulatory bursa, rays 9 and 10 long, comparable in length, and rays 9 strongly curved laterally at a right angle crossing ventrally rays 8; and females with a torsion of 180° to left of the posterior extremity. These characteristics were shared with Heligmostrongylus nematodes reported previously from O. phyllotis and Peromyscus yucatanicus (Cricetidae: Neotominae) also in the Yucatan Peninsula. The absence of intraspecific sequence variations in COI, and the low variation in D2-D3 expansion segments of 28S rRNA and ITS1 among the specimens obtained from the different hosts provided strong support that the worms found in the three rodent species belong to the same new species. The nine previously known species of Heligmostrongylus have been reported from caviomorph rodents of the families Cuniculidae, Dasyproctidae, Echimyidae, and Erethizontidae from the Neotropics. The occurrence of H. yucatanensis in three phylogenetically distant rodent species suggests that this nematode species could have the ability to expand its host range by colonizing new hosts.
A new Iranian population of Lindseyus costatus is characterized, including morphometrics, microphotographs, and molecular (18S, 28S rDNA) studies. It is compared with previously known populations. The results derived from molecular analyses failed to find close evolutionary relationships with other traditional genera of Belondiridae and Swangeriinae, adding more uncertainties about the internal phylogeny of the family. The taxonomy of Lindseyus is revised, with a new diagnosis, list of species, key to their identification, and a compilation of their main morphometrics.
We explore the necessarily comparative nature of CA’s methodology. We focus less on cross-linguistic comparisons, comparisons between talk-in-interaction in different settings, and comparisons between speakers from diverse speech communities. Instead, we consider the micro ways in which analysts work comparatively, ways that generally go unnoticed in accounts of CA’s methodology but which underpin our approach in data sessions, to building collections of phenomena, and even our research strategies when exploring certain linguistic or interactional forms. We demonstrate what can be learned from comparisons to be found in data, for example between the different responses by different participants to the same observation or question, or between different speakers’ versions of events, or from the different forms used by speakers when referring to the ‘same’ thing but in different action environments. We highlight the significance of speakers’ production of different versions of the ‘same’ something in their self-corrections. Finally, we illustrate the utility of a research strategy in which comparisons are made between speakers’ use of a certain reference form at one point in an interaction and the form they use at other points in the same interaction. In short, we explore the methodological significance of endogenous comparisons in data.
Mylonchulus laocaiensis sp. n. recorded from Vietnam, is described and illustrated, and its phylogenetic relationship within the Mylonchulidae family and Mononchida order are analysed. The new species is characterized by medium body size (L = 1.0–1.5 mm); buccal cavity goblet shaped, 26–29 × 14–16.5 μm or 1.8 (1.7–1.9) times as long as wide; posterior position of dorsal tooth apex (79%–88% from the base of buccal cavity); a small subventral tooth present on subventral wall; pars refringens vaginae with faint and small (2.5 × 1.7 μm) teardrop-shaped pieces, short pars distalis vaginae; male with short spicules (54–57 μm) with rounded head. The molecular data (18S and 28S rDNA) are provided for the new species.
A new species, Mesolepis arabellae, is described from material recently recovered from the shales of the Scottish Lower Coal Measure Formation. Up until now, three British species of Mesolepis have been named: Mesolepis scalaris Young, Mesolepis wardi Young, and Mesolepis micropterus Traquair. A fourth member of the genus, Mesolepis pustulosa Pruvost from the coalfields of Northern France, was named on scale description alone, though the validity of this taxon is uncertain. The new material described here varies from other Mesolepis species in its caudal peduncle morphology and overall body shape. Micro-computed tomography of the new species reveals the presence of teeth on the premaxilla and dentary and a splint-like fused prearticular and coronoid element, with implications for a possible feeding behaviour of Mesolepis. Additional information on the homogeneous Mesolepis wardi is also presented.
Most studies concerning parasitic infections in European bison have been performed on free-ranging animals: comparatively little is known about the abomasal nematodes of captive wisents, which are widely used in reintroduction programmes. The aim of the study was to determine the infection level and species composition of abomasal nematodes in captive European bison in enclosures (including zoos) and breeding centres compared to free-ranging individuals. It also includes a morphological analysis of the parasites based on figures and measurement data. Altogether, 11 species of nematodes were detected, with both captive and free-ranging animals demonstrating similar species compositions. Among those, 2 species of blood-sucking nematodes were detected, including Ashworthius sidemi and Haemonchus contortus. Interestingly, A. sidemi was found in almost all free-roaming animals, but only in 1 captive European bison. In addition, H. contortus was predominant in captive animals. The morphological identification was confirmed molecularly for 5 nematode species: A. sidemi, H. contortus, Ostertagia kolchida, O. ostertagi and Spiculopteragia boehmi. The identification was performed using small subunit ribosomal rDNA. The study provides the first available set of specular lengths of the gastric nematodes of European bison, and the first molecular data of O. kolchida and S. boehmi derived from the same host species. Our findings may simplify the morphometrical and molecular identification of Trichostrongylidae species infecting European bison, and can be useful in developing new management strategies for populations of this near-threatened species in Europe.
The cyst nematodes, subfamily Heteroderinae, are plant pathogens of worldwide economic significance. A new cyst nematode of the genus Cactodera within the Heteroderinae, Cactodera xinanensis n. sp., was isolated from rhizospheres of crops in the Guizhou and Sichuan provinces of southwest China. The new species was characterized by having the cyst with a length/width = 1.3 ± 0.1 (1.1–1.6), a fenestral diameter of 28.1 ± 4.3 (21.3–38.7) μm, vulval denticles present; second-stage juvenile with stylet 21.5 ± 0.5 (20.3–22.6) μm long, tail 59.4 ± 2.0 (55.9–63.8) μm long and hyaline region 28.7 ± 2.7 (25.0–36.3) μm long, lateral field with four incisures; the eggshell with punctations. The new species can be differentiated from other species of Cactodera by a longer tail and hyaline region of second-stage juveniles. Phylogenetic relationships within populations and species of Cactodera are given based on the analysis of the internal transcribed spacer (ITS-rRNA), the large subunit of the nuclear ribosomal RNA (28S-rRNA) D2-D3 region and the partial cytochrome oxidase subunit I (COI) gene sequences here. The ITS-rRNA, 28S-rRNA and COI gene sequences clearly differentiated Cactodera xinanensis n. sp. from other species of Cactodera. A key and a morphological identification characteristic table for the species of Cactodera are included in the study.