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The carbonate shell of rhynchonelliformean brachiopods is a relevant archive of seawater temperature / δ18O for the Phanerozoic. However, its application to investigate seasonality is under-exploited despite its wide employment to reconstruct the chemical conditions of past oceans. Indeed studies of brachiopod sclerogeochemistry are still rare compared to some other biogenic archives. In order to better understand if ontogenetic time-series faithfully record the seasonal variability of the surrounding environment, we investigated the incorporation of δ18O in the shell (δ18Oshell) of a modern temperate brachiopod species, Calloria inconspicua, living in the intertidal zone of Otago Harbor (New Zealand). After reconstructing the life history and ontogenetic age using morphological features of the valves, carbonate samples were collected from the inner fibrous layer along the maximum growth axis with a sub-millimetric resolution. Databases provided environmental parameters of seawater for comparison, and time-series of δ18Ofor equilibrium calcite (δ18Oeq) were estimated using salinity and temperature data. Results reveal that maxima and minima of δ18Oshell are well related to morphological markers highlighting yearly growth steps. The count of yearly cycles allowed an estimate of the timing of shell secretion and comparison with the estimated δ18Oeq of the surrounding environment.We found that C. inconspicua can be a robust archive for seasonal variation since it records with high fidelity the local condition of seawater in certain phases of its life. Although the application of the brachiopod shells in sclerogeochemistry and studies of past seasonality is promising, future researches should consider a few potential drawbacks which need to be taken into consideration. These include the fact that growth rate changes over the life-span and that shell is not deposited throughout the entire year (leading to under-estimation of the full seasonal range). Additionally, it is important to ensure that sampling does not sample different thickness within the shell, this returning time-averaged values. Knowledge of likely general biology, population composition, life cycle and shell structure are important prerequisites for the interetation of δ18O time-series measured on fossil brachiopod shells.

Background: Italy and especially Lombardy region was the first European Country hit by the covid 19 pandemic, without a proper preparedness plan. Italy’s health-care service is a regionally based National Health Service (NHS) that provides universal coverage, largely free of charge at the point of service. Aim of this paper is to analyse the national and especially the regional strategies put in place to face the pandemic, focusing on the impact of the overlap of the political and health competences among national and regional authority. Methods: Italian hygiene and preventive medicine society (SITI) realized a questionnaire submitted to National Institute for Health and regional stakeholder to investigate the response to the epidemic analysing the strategies and actions put in place both by the national and regional governments and the regional health authorities. Results: The national survey highlighted several critical points in the management of the covid 19 pandemic in the different regional contexts such as lack of personnel in preventive departments and preparadness. Conclusions: Lessons learnt during the pandemic should shape the future of the Italian health service. (www.actabiomedica.it)

Earth's transition from an icehouse to hothouse during the Late Paleozoic was characterized by a series of high paleolatitude glacial-interglacial events. However, the exact timing of these events remains unresolved. Here, we report on fifty-five calcitic shells of brachiopods and bivalves screened to obtain reliable 87Sr/86Sr ratios for Cisuralian (298.9-272.95 Ma) and Guadalupian (272.95-259.1 Ma) seawater. Specifically, we used well-preserved shells to build a 87Sr/86Sr seawater curve for the Sydney Basin, and then with the marine Look-up Table of the Permian calculated numerical ages of the stratigraphic succession. This allowed us to match seawater changes to the coeval P1 – P3 glacial-interglacial cycles recorded in the sedimentary successions of the Sydney Basin. Evaluation of the 87Sr/86Sr results revealed that onsets of the P2 and P3 glaciations in the Sydney Basin should be assigned to the early Artinskian and late Wordian, respectively. The range of 87Sr/86Sr values recorded by brachiopods from the Wandrawandian Siltstone coupled with recent geochronological dating of the Broughton Formation suggest that glacial phase P3 lasted about 2 Myr and was confined to the late Wordian – early Capitanian. Dating obtained using the Sr-isotope proxy from brachiopods agrees with the geochronologic ages, and they suggest that the glacial phases P1 to P3 became progressively shorter in duration and less intense. Conversely, the corresponding interglacials became progressively longer, and thus, documenting the gradual transition of the Permian icehouse to an ice-free greenhouse world. Our study confirms that strontium isotopes measured in screened brachiopod shell archives are sufficiently robust to date Paleozoic marine sedimentary successions, and are most valuable in sedimentary successions that otherwise lack geo-chronological dating.

The Permian/Triassic boundary approximately 251.9 million years ago marked the most severe environmental crisis identified in the geological record, which dictated the onwards course for the evolution of life. Magmatism from Siberian Traps is thought to have played an important role, but the causational trigger and its feedbacks are yet to be fully understood. Here we present a new boron-isotope-derived seawater pH record from fossil brachiopod shells deposited on the Tethys shelf that demonstrates a substantial decline in seawater pH coeval with the onset of the mass extinction in the latest Permian. Combined with carbon isotope data, our results are integrated in a geochemical model that resolves the carbon cycle dynamics as well as the ocean redox conditions and nitrogen isotope turnover. We find that the initial ocean acidification was intimately linked to a large pulse of carbon degassing from the Siberian sill intrusions. We unravel the consequences of the greenhouse effect on the marine environment, and show how elevated sea surface temperatures, export production and nutrient input driven by increased rates of chemical weathering gave rise to widespread deoxygenation and sporadic sulfide poisoning of the oceans in the earliest Triassic. Our findings enable us to assemble a consistent biogeochemical reconstruction of the mechanisms that resulted in the largest Phanerozoic mass extinction. The end-Permian mass extinction was linked with ocean acidification due to carbon degassing associated with Siberian Trap emplacement, according to boron isotopes from fossil shells and reconstruction of the carbon cycle.

A continuous strontium isotope profile with high-resolution sampling is desirable to calibrate multiple global events, realize temporal correlation among different continents, and understand tectonic history of the Permian Period. In this paper, we analyzed 90 micritic limestone samples from South China and 7 samples from Iran, with the aim to gain new 87Sr/86Sr data and obtain a curve of Sr isotopes for the Permian. The concentrations of Mg, Fe, Mn, and Sr are used to discriminate possible diagenesis of the samples. A comparison of those 87Sr/86Sr values between South China and southern Urals confirms that Sr-isotope proxy has the potential to be used for time calibration and correlation in regions where biostratigraphic or radiometric markers are not available. The 87Sr/86Sr curve obtained in this study shows a trend comparable with the LOcally WEighted Scatterplot Smoothing (LOWESS) regression curve from the previous studies. A continuous decline trend from the latest Carboniferous to late Guadalupian was shown, and the lowest 87Sr/86Sr values in the late Capitanian was constrained within the interval from the conodont Jinogondolella shannoni/J. altudaensis to J. xuanhanensis zones. It is followed by an increasing trend to more radiogenic values in the Lopingian with a minor fluctuation in the early Wuchiapingian. We consider that mid-ocean ridge spreading and increasing continental weathering during the transition from convergence to the breakup of Pangea as the dominant factors driving the changes of the seawater Sr isotope ratios.

The Permian Period is punctuated by Earth system changes unlike any other in geological history. The start of the Permian witnessed the termination of the Late Paleozoic Ice Age, followed by the climatic transition from icehouse to greenhouse conditions. The Guadalupian-Lopingian (Middle-Late Permian) was characterized by two biocrises associated to volcanisms: (i) the end-Guadalupian crisis and (ii) the end-Permian mass extinction. Seawater Sr isotope (87Sr/86Sr) records can shed light on the evolution of the Permian Earth system. The Permian 87Sr/86Sr record suffers from a number of issues including low resolution and potential diagenetic alteration. In this paper, we summarize the existing Permian 87Sr/86Sr records and focus on the current challenges. We also present a new, high-resolution Permian 87Sr/86Sr curve derived from pristine brachiopod shells based on data resulting from careful diagenetic screening. Our new record shows that the 87Sr/86Sr of seawater decreased continuously from the earliest Permian to the middle Capitanian (late Guadalupian), with the lowest ratio of 0.706832 registered in the Colania douvillei-Kahlerina pachiytheca Zone. Subsequently, 87Sr/86Sr ratios increased from the late Capitanian to the latest Permian and reached a ratio of 0.707167 just 0.8 m below the first occurrence of the Hindeodus parvus. We employed a stochastic oceanic box model to explore the potential drivers of the Permian seawater Sr isotope record. Our results support that changes in the hydrothermal input, rather than changes in continental weathering intensity, are the most likely controlling factor for the observed variations in Permian seawater 87Sr/86Sr. Therefore, we suggest that the marine hydrothermal system (and hence ocean basin dynamics and deep-sea temperatures) may have been the driver of the pronounced decreasing 87Sr/86Sr trend across the Permian.

We investigated the kill mechanisms of the end-Permian mass extinction by analyzing patterns in biomineralization of marine invertebrates. The microstructures of Upper Permian brachiopod organocarbonate shells show the demise of the production of fabrics with a columnar layer—which has less organic matrix—in favor of more organic-rich shells at the end of Permian. Also, in the 100–120 k.y. interval prior to the Permian-Triassic boundary (PTB), the Rhynchonellata had small calcite structural units (fibers) and thus a higher shell organic content, whereas the Strophomenata were not able to produce smaller units. This suggests that the two classes had a different capacity to cope with environmental change, with the Rhynchonellata being more able to buffer against pH changes and surviving the PTB, whereas the Strophomenata became extinct. The observed trends in biomineralization are similar to the patterns in extant marine invertebrates exposed to increasing p CO 2 and decreasing pH, indicating that ocean acidification could have been one of the kill mechanisms of the mass extinction at the PTB.

Due to epidemiological and social changes related to the increase in the average life expectancy, hospital users are characterized by elderly chronic and comorbid patients who require recurrent hospitalizations often with disability outcomes. In this framework, an innovative clinical and management hospitalization model is the adequate answer to systematically promote the patient independence. Main features are interdisciplinary and integrated care pathways facing both disease and disability biologically and functionally diagnosed by ICD and ICF. The definition, personalization of pathways/protocols and outcome evaluation represent the foundations of this new model for patient care. The digitalization of hospital clinical data and medical knowledge make the model feasible and fitting the recent WHO guideline: recommendations on digital interventions for health system strengthening.A causa dei cambiamenti epidemiologici e della società legati all’aumento della aspettativa di vita i pazienti che afferiscono in ospedale sono generalmente più anziani, cronici e comorbidi e richiedono frequenti re-ospedalizzazioni spesso con esiti disabilitanti. In questo contesto un nuovo modello di ospedalizzazione innovativo sia dal punto di vista clinico che di management sembra essere la risposta adeguata per promuovere sistematicamente l’autonomia del paziente. Caratteristiche principali del modello sono l’interdisciplinarietà e percorsi di cura integrati che affrontino la malattia e la disabilità valutate con le classificazioni ICD e ICF. Le basi fondanti di questo nuovo modello di cura sono la definizione e la personalizzazione dei percorsi diagnostico terapeutici assistenziali (PDTA). La digitalizzazione dei dati clinici ospedalieri ricavati dai percorsi/protocolli rendono fattibile il modello e si allineano con le recenti line guida dell’OMS sulla digitalizzazione degli interventi nel rafforzare i sistemi sanitari.

Climatic warming has been widely cited as a driver for many mass extinction events in Earth history, including the middle-late Permian Guadalupian-Lopingian boundary (GLB) mass extinction and end-Permian mass extinction (EPME) investigated in this study. However, the role of warming in driving the EPME event is under debate because current paleotemperature studies indicate the rapid increase in sea-surface temperature postdate the onset of the EPME event, and a reliable paleotemperature record across the GLB event is lacking. Here, we present a high-resolution and successive δ 18 O record using low-Mg calcite shells of brachiopods (bLMCs) from a single stratigraphic section in central China to reconstruct paleotemperature changes from the middle to the latest Permian. After a rigorous screening for diagenesis, our data show a ∼1.0‰ decrease in δ 18 Ocalcite (and thus climatic warming) during the middle Capitanian, followed by a gradual ∼2.0‰ increase (climatic cooling) during the late Wuchiapingian. From the latest Wuchiapingian to the early Changhsingian, δ 18 O decreased gradually and reached the lowest values of -4.0‰ (and thus rapid climatic warming) immediately before the Permian-Triassic boundary. The two warming events are coeval with the onset of the Emeishan Large Igneous Province and the Siberian Traps Large Igneous Province, respectively, suggesting the two volcanic events are the plausible drivers of these climatic warming events. A close comparison of paleontological and geochemical records indicates that the warming events occurred predate the GLB and EPME events, this is in contrast with conodont δ 18 Oapatite data which document the rapid climatic warming lagged the onset of the extinction event. The comparison between δ 18 O of bLMCs and δ 18 O of conodonts from the same section shows that the long-term trends are similar, but, at higher temporal resolution, discrepancies are present, entailing further investigation in the near future. Our study confirms that δ 18 O of the brachiopod shells underwent important changes during the end of Paleozoic, highlighting that sea surface temperature is a key factor to understand the biosphere history, since it changes simultaneously with the biological crises, and that bLMCs are invaluable archive for tracking physical and chemical conditions of past oceans.

Shells of brachiopods are excellent archives for environmental reconstructions in the recent and distant past as their microstructure and geochemistry respond to climate and environmental forcings. We studied the morphology and size of the basic structural unit, the secondary layer fibre, of the shells of several extant brachiopod taxa to derive a model correlating microstructural patterns to environmental conditions. Twenty-one adult specimens of six recent brachiopod species adapted to different environmental conditions, from Antarctica, to New Zealand, to the Mediterranean Sea, were chosen for microstructural analysis using SEM, TEM and EBSD. We conclude that: 1) there is no significant difference in the shape and size of the fibres between ventral and dorsal valves, 2) there is an ontogenetic trend in the shape and size of the fibres, as they become larger, wider, and flatter with increasing age. This indicates that the fibrous layer produced in the later stages of growth, which is recommended by the literature to be the best material for geochemical analyses, has a different morphostructure and probably a lower organic content than that produced earlier in life. In two species of the same genus living in seawater with different temperature and carbonate saturation state, a relationship emerged between the microstructure and environmental conditions. Fibres of the polar Liothyrella uva tend to be smaller, rounder and less convex than those of the temperate Liothyrella neozelanica, suggesting a relationship between microstructural size, shell organic matter content, ambient seawater temperature and calcite saturation state.

In the light of the growing complexity featuring the contemporary world, a future challenge is represented by the maintenance of the humanization of healthcare, along with the necessity of a high specificity personalized treatment, in a growing emergency of lack of resources. Furthermore, the ongoing digital revolution spreading in every productive sector involves the health-care system as well, playing a crucial role for the goals of the specialized care-related prevention-treatment-rehabilitation approach of the Rehabilitation Medicine. However, the digitalization of clinical data is not to be considered as a mere tout-court necessity, but it deserves to be planned and carried out with consistent awareness: the digital transformation calls for a theoretical paradigm which, together with a shared language, will be able to embrace its multilevel complexity, taking into account the patient needs, the clinical care pathways and the administrative requests.In the present work the potentialities of the WHO ICF model (International Classification of Functioning, Disability and Health) will be described. In particular, will be discussed the role of the ICF in representing the keystone able to connect the ICD-9-CM classification, the clinical care pathways, the individualized rehabilitation project and program and their digital implementation.Hence, each step of the process that led the implementation of the biopsychosocial model in the ICF Maugeri workflows will be presented, as well as the critical issues related to the digitalisation process and the strengths in safeguarding the patients' wellbeing.In un’ottica di crescente complessità caratterizzante il mondo contemporaneo, la sfida per il futuro è il mantenimento dell’umanizzazione della cura, affiancato alla necessità di un’assistenza personalizzata, ad alta specificità, che possa essere attuabile in un contesto di riduzione delle risorse disponibili. Inoltre, la rivoluzione digitale in atto in ogni settore produttivo coinvolge anche l’ambito sanitario, costituendo una sfida importante per gli orizzonti della Medicina delle Cure Specialistiche Correlate Riabilitative. La digitalizzazione del dato clinico non si profila tuttavia come mera necessità tout-court ma va pianificata e condotta con consapevolezza: tale trasformazione necessita di un riferimento teorico elettivo che, insieme a un linguaggio condiviso, possa abbracciarne le complessità multilivello senza negligere le necessità del paziente, la gestione dei percorsi diagnostici e terapeutici e le richieste amministrative. Nel presente lavoro vengono descritte le potenzialità del modello ICF (Classificazione Internazionale del Funzionamento, della Disabilità e della Salute) nel rappresentare l’elemento cardine in grado di collegare la classificazione ICD-9-CM, i percorsi diagnostici terapeutici assistenziali (PDTA), il Progetto Riabilitativo Individualizzato (PRI) e il programma riabilitativo individualizzato e la sua implementazione in un sistema digitale. Vengono presentate le fasi del processo che guidano l’implementazione del modello biopsicosociale ICF nei percorsi della medicina riabilitativa in ICS Maugeri, le criticità legate alla sua informatizzazione e i punti di forza in grado di garantire il mantenimento di un approccio orientato al bene del paziente.

The end of the Permian was a time of great death and massive upheaval in the biosphere, atmosphere and hydrosphere. Over the last decades, many causes have been suggested to be responsible for that catastrophe such as global warming, anoxia and acidification. The Gyanyima limestone block was an open ocean seamount in the southern Neotethys at subtropical latitude, and it affords us insight into open-ocean oceanographic changes during the end of the Permian. After careful screening using multiple tests, we reconstructed carbonate/seawater curves from the geochemical data stored in pristine brachiopod shell archives from the shallow water limestone of the Changhsingian Gyanyima Formation of Tibet. The reconstructed strontium isotope curve and data for the late Changhsingian are relatively invariant about 0.707013, but in the upper part of the succession the values become more radiogenic climaxing at about 0.707244. The 87 Sr/ 86 Sr curve and trend are similar to those observed for the Upper Permian succession in northern Italy, but dissimilar (less radiogenic) to whole rock results from Austria, Iran, China and Spitsbergen. The Ce/Ce* anomaly results ranging from 0.310 to 0.577 for the brachiopods and from 0.237 to 0.655 for the coeval whole rock before the event, and of 0.276 for whole rock during the extinction event, suggest normal redox conditions. These Ce* values are typical of normal open-ocean oxic water quality conditions observed in modern and other ancient counterparts. The biota and Ce* information clearly discounts global anoxia as a primary cause for the end-Permian biotic crisis. Carbon isotopes from brachiopod shells and whole rock are relatively invariant for most of the latest Permian interval, which is in stark contrast to the distinct negative carbon isotope excursion observed near and about the event. Estimates of seawater temperature at shallow depth fluctuated from 22.2 to 29.0 °C up to unit 8–2, and then gradually rise from 29.7 °C in unit 8–13 to values exceeding 35 °C at a stratigraphic level about 120 ky before the Permian–Triassic boundary, and just before the onset of the extinction interval. This dramatic increase in seawater temperature has been observed in global successions from tropical to mid latitude and from restricted to open ocean localities (e.g., northern Italy, Iran). The brachiopod archive and its geochemical proxies from Tibet support the paradigm that global warming must have been an important factor of the biotic crisis for the terrestrial and marine faunas and floras of the late Paleozoic world.

Calcareous shells of Rhynchonelliform brachiopods from the Nesen Formation (Late Permian) of Iran were studied by scanning electron microscope, cathodoluminescence and trace element chemistry to define their microstructure and state of preservation. In the Strophomenata shell succession, the secondary layer consists of cross-bladed, laminar calcite, and in a few species there is a tertiary layer of prisms. In the Rhynchonellata shell succession, the secondary layer consists of elongated fibers and the tertiary layer of prisms. All specimens were classified into six micromorphological types based on the fabric of the layer and the morphology of their microstructural units (laminae, fibres and prisms). Shell micromorphology and enclosing whole rock were further analyzed by cathodoluminescence and trace chemistry to assess preservation of brachiopod low-Mg calcite and specifically of their layers and microstructural units. Relative color frequencies were determined for each morphological type and degree of luminescence based on the lithology of the host rocks to evaluate the main factors that affect shell preservation. Results suggest that diagenetic alteration may depend on shell fabric and taxonomy as well as lithology of the host rock, but it appears that the first and the second features are the most important factors in determining the degree of brachiopod low-Mg calcite preservation. In general, the fibrous secondary layer is likely more often and better preserved than its laminar counterpart irrespective of host rock lithology. Furthermore, tertiary layers tend to be better preserved than secondary ones in Rhynchonellata low-Mg calcite shells, whereas no preferential preservation of either layer over the other was observed in the shells of Strophomenata. This information is important when selecting fossil brachiopod low-Mg calcite shells as geochemical proxies for paleoclimatic, paleoecologic, paleoenvironmental and other studies.

The spermatozoon of Tubiluchus troglodytes, the first priapulid formally described from the Mediterranean Sea has a head composed of an acrosome and a nucleus. The acrosome is divided in two branches coiled around the nucleus. The nucleus is basally columnar, but apically generates two rods helically coiled one around the other. The midpiece is formed by an axoneme with 27 accessory microtubules, surrounded by three mitochondria. An annulus separates the midpiece from the tail that contains a 9 + 2 axoneme surrounded by nine accessory microtubules. The spermatozoon of T. troglodytes is similar to that of the other two species known from the genus, and completely different from the 'primitive' one of the other priapulids. Since Tubiluchus is considered the most basal of the extant priapulids, and the only genus with an internal fertilization, it may be that in priapulids the external fertilization is a derived character.

The Julfa Formation in the Ali Bashi Mountains, northwest Iran, is very rich in brachiopods, particularly in its lower part, which has been dated by fusulinids and conodonts as Wuchiapingian in age. The brachiopod fauna described herein has been collected along the Main Valley section of the Ali Bashi Mountains, several hundred metres away from the historical sections described in the 1960’s and 1970’s. It comprises 39 species of the orders Productida, Orthotetida, Orthida, Rhynchonellida, Athyridida, Spiriferida, and Terebratulida, most of which are known in the coeval successions of Transcaucasia, Alborz Mountains in north Iran and in South China, confirming the Wuchiapingian age indicated by other proxies. A few of the brachiopod taxa range up into the Changhsingian Paratirolites Limestone. The shale and marly limestone at the base of the formation are dominated by semi-infaunal productids, that are progressively succeeded near the top of the lower part of the formation by a more diverse range of pedicle attached and cemented taxa, suggesting a shallowing upward trend and a shift to higher nutrient-substrates in more turbulent waters. The successive deepening trend recorded in the upper part of the Julfa Formation and in the overlying Ali Bashi Formation is very unfavourable for the brachiopods and only a few species survive, represented by small sized pediculate taxa that thrive on hardgrounds., Rivista italiana di Paleontologia e Stratigrafia, Vol 120, No 1

Here, we provide the dataset associated with the research article “Mapping of recent brachiopod microstructure: A tool for environmental studies” [1] . We present original data relative to morphometric and statistical analyses performed on the basic shell structural units (the secondary layer fibres) of brachiopod shells belonging to six extant species adapted to different environmental conditions. Based on SEM micrographs of the secondary layer, fibres from ventral and dorsal valves, and from different shell positions, showing regular and symmetrical cross sectional outlines, were chosen for morphometric measurements using Adobe Photoshop CS6, Image-Pro Plus 6.0 and ImageJ. To work out the reliability of the measurements, the most significant parameters were tested for their probability density by distribution plots; for data visualization and dimension reduction, principal component analysis (PCA) was performed using R 3.3.0 [2] and independent-samples t-tests were performed using SPSS Statistics (IBM Version 22.0. Armonk, NY). Besides a quantitative analysis, a qualitative description of the shell microstructure is provided by detailed SEM imaging and EBSD measurements.

The study of the shell microstructure of brachiopods is fundamental to understand their evolutionary history and their biomineralization process. Here, species of forty Lopingian brachiopods genera, representative of twenty-seven different families, are investigated using the Scanning Electron Microscope. The investigated specimens come from different paleogeographic localities in the Palaeotethys/Neotethys oceans. The studied brachiopods show a large variability of the shell fabric, which is mainly related to the organization of its structural units: laminae, fibers and columns, possibly crossed by pseudopunctae or punctae. For the Strophomenata, the laminar fabric of Productida is crossed by pseudopunctae with taleolae and the laminae are often organized in packages, with the blades oriented about perpendicular to each other; this feature is less evident in the laminar Orthotetida, which bear pseudopunctae without taleoae. For the Rhynchonellata, fibrous fabrics are either impuctate in the Spiriferida, most Athyridida and Rhynchonellida, or with punctae, as observed in the Orthida, Terebratulida and in the Neoretziidae (Athyridida). The fibers show a range of sizes and shapes also in the same specimens and the transition to the columnar layer is different than in Strophomenata. The arrangement of the structural units revealed that the disposition of the organic membranes, on which biomineralization took place, was highly variable among the taxa. On the other hand, two distinctive features are analogous among distantly related groups, i.e. the Strophomenata and the Rhynchonellata: the presence of a columnar tertiary layer underlying the secondary fabric and the alternations between fibers/laminae of the secondary layer and columns of the tertiary layer. This suggests that there are common factors controlling the development and evolution of the shell fabric in all rhynchonelliformean brachiopods that can be linked to their taxonomical position, to their environmental requirements and to constraints imposed by their low-energy life-style. This should be taken into account to understand how these calcifying organisms responded and will respond to environmental and climate change in past and future times., Rivista Italiana di Paleontologia e Stratigrafia (Research In Paleontology and Stratigraphy), Vol 123, No 3 (2017)