In Clear Creek, which runs through the Iowa State University campus in Ames, Iowa, USA, several types of iron mineralisation occur within stagnant pools and slow-moving water. This includes rusty flocs, commonly observed in mineral springs, rust-stained sediments and iridescent films (‘schwimmeisen’) on the pool surfaces. Observations of iron mineralisation over the course of more than a year in a single reach indicated that mineralisation occurred after precipitation events once water levels in the stream had dropped. Iron extracted and quantified from Clear Creek sediments and pool waters indicated the stream and its sediments were unlikely to be supplying the iron for mineralisation. We hypothesise that the observed mineralisation could result from the discharge of shallow, reducing groundwater-bearing Fe(II) into stagnant pools that form in debris-dammed areas of the stream. Piezometers installed next to the creek documented that shallow groundwater contained dissolved Fe, with the source of Fe being the floodplain sediments and the hydraulic gradient promoted groundwater discharge into the stream. Microorganisms identified in mineralised pools using 16S rRNA amplicon sequencing revealed an elevated presence of putative iron-oxidizing and iron-reducing microorganisms in mineralised vs. non-mineralised pools. Further investigation of the iridescent films revealed them to be composed of amorphous Fe(III) minerals. We further hypothesise that microbial exudates reduce surface tension and potential micro-zones for subsequent microbial iron redox cycling with dissolved organic matter in the pools. Determining the processes controlling mineralisation can lead to a better understanding of the ecological role of iron mineralisation in agricultural watersheds and the importance of contaminant degradation and nutrient cycling.

Identifying cryptic species and juveniles in the Ophiuroidea has always been a challenge. However, post-larval developmental studies have the potential to uncover the identity of these cryptic species and juveniles, as they offer valuable information that is not often found in adults. Although the importance of studying growth series is well-known in ophiuroids, it is difficult to obtain and identify the juvenile stages. For this reason, most studies are restricted to brooding species and information is lacking for many species, including those of the genus Ophiocoma. In this study, a growth series was developed to show the main differences during the development of two similar species of Ophiocoma: Ophiocoma echinata and Ophiocoma trindadensis. Using morphometry and scanning electron microscopy, we describe in detail the juveniles, intermediate stage, and adults of O. echinata and O. trindadensis. Differences in the shape of the ventral arm plate and dorsalmost arm spines, the number of tentacle scales, and the presence of granules ventrally were highlighted in the separation and identification of juveniles of both species.

Concentrations of sedimentary molybdenum (Mo) have been used as a proxy for palaeoceanographic redox conditions based on the distinctive behaviour of Mo under oxic versus euxinic (i.e., anoxic and sulfidic) conditions. However, the mechanisms that govern Mo sequestration in various euxinic settings are not fully resolved. It has previously been proposed that sulfate-reducing bacteria (SRB), the main drivers and regulators of euxinic conditions, can actively take up and reduce Mo intracellularly and passively induce Fe-independent Mo complexation and reduction at their cell surfaces. However, uncertainties remain regarding the underlying interactions and relative contributions of these proposed biotic Mo sequestration pathways. In this study, systematic experiments were carried out to examine the interactions among Mo(VI) species (MoO42- or MoS42-), ferrous iron (Fe2+) and SRB with a focus on combinations of conditions that lead to reductive Mo precipitation. The speciation of aqueous Mo and composition, structure, oxidation states and bonding environment of precipitated Mo-sulfides were analysed using UV-vis spectrophotometry (UV-vis), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and synchrotron-based X-ray absorption spectroscopy (XAS). Results indicate that SRB does not directly reduce Mo but, rather, plays a passive role in mediating Mo sequestration by providing sulfide and potential nucleation sites at their reactive cell surfaces for precipitation. However, even in the presence of SRB cells, Fe2+ was required for Mo precipitation in all conditions tested. By identifying the limiting (and non-limiting) factors in the Mo reduction and sequestration process, this study provides significant new insights for interpreting Mo palaeoredox proxies.

Differences in brachyuran morphology among and between juveniles and adults as well as sexual dimorphism are not well studied among extinct brachyuran crabs. Carapace dimorphism and morphological changes during growth have received little attention in fossil crabs. Tetracarcinus subquadratus Weller, 1905, Dakoticancer australis Rathbun, 1935, and Seorsus wadei Bishop, 1988 are herein synonymized on the basis of examination of dozens to hundreds of specimens of each from the same locality. Synoriacarcinus new genus is named to embrace two species previously referred to Seorsus Bishop, 1988, Synoriacarcinus millerae (Bishop, 1992), new combination, and Synoriacarcinus kauffmani (Feldmann et al., 2013), new combination. Both Dakoticancridae and Ibericancridae were well established on coastal North America during the Late Cretaceous but became extinct in the end-Cretaceous event.

UUID: http://zoobank.org/2eab7247-6235-435d-8eb1-b40d5a633e2b

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.

This work focuses on the study of three pelagic fish species of the same genus, caught from the south-western coasts of the Mediterranean. It concerns lipid content, fatty acid profile and nutritional quality (atherogenic index, thrombogenicity index, ratio between hypocholesterolemic and hypercholesterolemic fatty acids and n6-to-n3 ratio) of Trachurus trachurus, Trachurus mediterraneus and Trachurus picturatus. Lipid extraction and esterification were carried out on the flesh of each species, and fatty acid methyl esters were analysed using gas chromatography-mass spectrometry. The obtained results show that lipid content mean values vary between 2.87 and 5.06%, saturated fatty acids contents range from 37.51 to 53.23%, monounsaturated fatty acids content range from 29.24 to 37.65% and polyunsaturated fatty acids content range from 9.11 to 33.24% according to species. Also, the different mean values of indexes describing the nutritional quality vary significantly depending on species. That confirms the good quality of studied species and their importance for human nutrition and health, hence the urgent need to preserve their stocks.

Ulakhan Sular provides one of the largest natural stratigraphic sections through ancient permafrost deposits in the Batagay–Betenkes region of the Yana Uplands of western Beringia, but their depositional environment, age, and paleoenvironmental significance are uncertain. To address these uncertainties, we report the results of reconnaissance observations of the stratigraphy, sedimentology, paleosols and soil-like bodies, plant and insect macrofossils, and geochronology of the permafrost deposits at the stratotype section of the Ulakhan Sular Formation. Sedimentologically, this formation is dominated by well-sorted, fine to very fine sand that contains fluvial, aeolian, and permafrost sedimentary structures consistent with deposition near the paleo-Adycha River. The fluvio-aeolian deposits have similarities and differences to periglacial fluvio-aeolian and aeolian deposits in modern arctic regions of Canada and Greenland, and Pleistocene deposits in Alaska, China, and northwest Europe. The remarkable thickness of aeolian deposits (~50 m) at Ulakhan Sular is attributed to abundant local sand sources, ample accommodation space, and intensive aeolian transport and deposition. Optically stimulated luminescence dating of quartz sand and post-infrared–infrared dating of K-feldspar sand suggests deposition of the Ulakhan Sular Formation during late Marine Oxygen Isotope Stage (MIS) 6 or MIS 5. The aeolian sand-sheet deposits are correlated with other cold-climate aeolian sand and silt (loess) deposits in Beringia and southern Siberia, indicating a regional episode of aeolian sand transport and deposition at a similar time to glaciation by the Eastern Siberian Ice Sheet.

The present study described and illustrated the larval morphology of the three first zoeal stages (zoea I–III) of Synalpheus fritzmuelleri and compared with the previous described larvae of this species. The results pointed out a variety of differences among the descriptions, most of them related to the type and number of setae and articulation of appendages. The first zoea demonstrates similarities shared with the zoea I within the genus besides the diagnostic described characteristics. Other incongruences were also found such as the lack of information about some structures, such as the maxillule in the zoea I, and the use of ambiguous terms do designate type of setae. Moreover, the more advanced the zoea, additional differences were found among the previous and the current descriptions. Due to that, the necessity to review and also add new descriptions for Synalpheus larvae proves imminent to establish a standardization in the morphological description that will strengthen the comparative relationship in the genus.

Revision of the type species of the Early Ordovician (Tulean, late Tremadocian) bathyurid trilobite Licnocephala Ross, 1951 demonstrates that it has significantly different morphology than that ascribed to it in the earlier literature, which was based largely on species now assigned to a different genus. In addition to the type species, L. bicornuta Ross, 1951, which is fully revised on the basis of new material, four species, all apparently new, have been recovered, two of which, L. ngi n. sp. and L. bradleyi n. sp., are well enough known to formally name. The overall phylogenetic structure of bathyurids is yet to be determined, but several apparent clades can now be recognized and are discussed. Among these is what is termed the “Chapmanopyge group,” including Chapmanopyge Fortey and Bruton, 2013, Punka Fortey, 1979, Uromystrum Whittington, 1953, and Licnocephala. These genera are united in the occurrence of much of the anterior cephalic border on the librigenal anterior projection, with most of the anterior margin of the cranidium representing the suture, the possession of very short (exsag.) strap-like posterior cranidial projections, and extremely narrow visual surfaces. A fifth genus of the group, Ibexocephala n. gen., is represented by two new species, I. lossoae (type species) and I. dekosterae. The taxon features a remarkable cranidial morphology involving a strong deflection of the posteriormost part of the cranidium from the anterior part in sagittal profile.

UUID: http://zoobank.org/ab9a8796-84c7-48b1-b0e5-84a22511a6b4

The Japanese flying squid, Todarodes pacificus, is distributed mainly in the northwest Pacific and the Japan Sea. The present study was conducted for a better understanding of the mechanisms behind its migration routes. The ratios of strontium to calcium (Sr:Ca) in the statoliths can be associated with the water temperatures the squid experienced in the sea. Using specimens collected in the northern Japan Sea in summer and Lagrangian backward tracer experiments, a strong negative correlation was obtained between the Sr:Ca in the statoliths and the empirical water temperatures estimated through a regional ocean model. These backward tracer experiments were continuously conducted at depths of 6, 15, and 30 m. The greatest determination coefficient of the regression expression appeared for a nearshore tracer group of the experiment at a depth of 15 m. In addition, the regression expression provided reasonable lifetime empirical water temperature variations of the squids collected in the sea areas east of Tsushima Island and west of the Goto Islands in winter. The combination of Ca:Sr analytical chemistry and tracer experiments with the ocean dynamic model used in this study improved our understanding of the migration path of T. pacificus.

Federal and local agencies have identified a need to create building databases to help ensure that critical infrastructure and residential buildings are accounted for in disaster preparedness and to aid the decision-making processes in subsequent recovery efforts. To respond effectively, we need to understand the built environment—where people live, work, and the critical infrastructure they rely on. Yet, a major discrepancy exists in the way data about buildings are collected across the United SStates There is no harmonization in what data are recorded by city, county, or state governments, let alone at the national scale. We demonstrate how existing open-source datasets can be spatially integrated and subsequently used as training for machine learning (ML) models to predict building occupancy type, a major component needed for disaster preparedness and decision -making. Multiple ML algorithms are compared. We address strategies to handle significant class imbalance and introduce Bayesian neural networks to handle prediction uncertainty. The 100-year flood in North Carolina is provided as a practical application in disaster preparedness.

There is a pressing need for novel approaches to help address climate change and for a workforce that is equipped with a combination of new and different types of knowledges. The One Health (OH) core competencies perhaps offer the new knowledges, skills and attitudes that will be needed in a future generation of practitioners that does not shy away from complexity. The objective of this research was to identify overlapping and transferable OH-climate change competencies that are needed of professionals working to address climate change. Using focus groups and qualitative content analysis, 23 professionals from across Canada whose employment positions had a key focus on climate change were brought together across five sessions. Participants agreed that the OH competencies were applicable to their employment roles and responsibilities, but they identified four key missing areas that are important for graduates: evaluative and reflective practice, personal resilience, turning knowledge into action and having an openness to other knowledges (particularly Indigenous and non-Western viewpoints). This work also provided a first iteration of a process that should be continually used to bridge the gap between theory and practice, as employer needs are a key consideration during the development of educational programs.

Members of the genus Actinia are familiar members of rocky shore communities across much of the world. However, to date, no Actinia species have been reported from the North American continent. Here, we report Actinia from an approximately 22 km length of the New Jersey, US shoreline, where it was first discovered in 2021. Morphology and DNA barcoding data (mitochondrial cytochrome c oxidase I and nuclear internal transcribed spacer) indicate that these populations are Actinia equina. The presence of these populations close to major ports in New Jersey, New York, and Philadelphia suggests a probable introduction from shipping activities.