The ontogeny of Belosaepia ungula Gabb, 1860 from the Crockett Formation (Bartonian stage, Eocene) of Texas is documented for growth from embryo to old age. During the last stage of life, much skeletal resorption occurred, resulting in a major change in form of the skeleton. the animal produced a large skeleton (to 180 mm in length and 50 mm in diameter) with endogastric coiling, oblique septa and a very large siphuncle. the skeleton has a guard with a solid posterior prong, a posteroventral corona plate and a noded dorsal shield. the ventral margin of the skeleton consists of a thin flattened deck containing strongly recurved septa, conotheca and a secondary prismatic shell layer. New terms are defined for features of the skeleton not previously described. the microstructure of the ventral deck and the presence of a rod structure between the prong and callus are described for the first time. Chamberlets similar to those in living Sepia cuttlebones are present between closely spaced septa and they vary from walled units on lateral margins to pillar form in mid-ventor. the siphuncle is secondarily thickened within the dorsal interior, producing a siphuncle band. the skeleton was produced by a deep-bodied animal of demersal life habits. the species B. uncinata, B. harrisi and B. alabamensis voltzi proposed by Palmer (1937) are synonymised with B. ungula. the species B. veatchii and B. saccaria of Palmer (1937) are considered to be valid species, but B. alabamensis proposed by Palmer (1937) is synonymised with B. veatchii. Descriptions of belosaepiid species must be based only on specimens of adult size that have not been affected by resorption.
Given the longstanding controversy about hypnosedative use, we aimed to investigate the attitudes of prescribing psychiatrists and service users towards long-term use of hypnosedative medication, and their perceptions of barriers to evidence-based nonmedication alternatives. Qualitative data from focus groups in Aotearoa/NZ were analysed thematically. A novel research design involved a service user researcher contributing throughout the research design and process. Service users and psychiatrists met to discuss each other's views, initially separately, and subsequently together. Analysis of the data identified four key themes: the challenge, for both parties, of sleep disturbance among service users with mental health problems; the conceptual and ethical conflicts for service users and psychiatrists in managing this challenge; the significant barriers to service users accessing evidence-based nonmedication alternatives; and the initial sense of disempowerment, shared by both service users and psychiatrists, which was transformed during the research process. Our results raise questions about the relevance of the existing guidelines for this group of service users, highlight the resource and time pressures that discourage participants from embarking on withdrawal regimes and education programmes on alternatives, highlight the lack of knowledge about alternatives and reflect the complex interaction between sleep and mental health problems, which poses a significant dilemma for service users and psychiatrists.
The hyperthermal events of the Cenozoic, including the Paleocene-Eocene Thermal Maximum, provide an opportunity to investigate the potential effects of climate warming on marine ecosystems. Here, we examine the shallow benthic marine communities preserved in the late Cretaceous to Eocene strata on the Gulf coastal plain (United States). in stark contrast to the ecological shifts following the end-Cretaceous mass extinction, our data show that the early Cenozoic hyperthermals did not have a long-term impact on the generic diversity nor composition of the Gulf Coastal Plain molluscan communities. We propose that these communities were resilient to climate change because molluscs are better adapted to high temperatures than other taxa, as demonstrated by their physiology and evolutionary history. In terms of resilience, these communities differ from other shallow-water carbonate ecosystems, such as reef communities, which record significant changes during the early Cenozoic hyperthermals. These data highlight the strikingly different responses of community types, i.e., the almost imperceptible response of molluscs versus the marked turnover of foraminifera and reef faunas. the impact on molluscan communities may have been low because detrimental conditions did not devastate the entire Gulf Coastal Plain, allowing molluscs to rapidly recolonise vacated areas once harsh environmental conditions ameliorated.Human activities are drastically changing conditions in coastal marine ecosystems by polluting, destroying habitats, overexploiting resources, enabling invasive species, and driving climate warming. Increased greenhouse gas emissions associated with these activities harm marine communities by expanding hypoxic dead zones, increasing ocean acidity, and causing thermal stress 1,2 . In order to understand how communities will respond to climate-related stressors, we look to potential deep-time analogues and the community shifts recorded by fossils. The Eocene witnessed two separate long-term warming trends of ~6 °C culminating in the late Ypresian and Bartonian, known as the Early Eocene Climatic Optimum (EECO) and the Middle Eocene Climatic Optimum (MECO), respectively (Fig. S1). Superimposed on these long-term trends are many short-lived intervals of increased carbon injection into the atmosphere and increased sea surface temperatures, known as hyperthermals, and of these the Paleocene-Eocene Thermal Maximum (PETM) and the Eocene Thermal Maximum 2 have the highest magnitude and pace 3 (Fig. S1). It has been argued that these hyperthermal events represent the best analogues for projected climatic change, as they were caused by rapid increases in pCO 2 and involved various environmental consequences, such as ocean acidification and intensification of the hydrological cycle 2,4 . In addition, the peak of the MECO saw rapid warming 5 and could be considered another hyperthermal. Similar hyperthermal events of smaller magnitude have also been recorded from the Paleocene, e.g., the latest Danian Event 6 .The PETM was the m...
A comprehensive discussion and survey is made of all North American Paleogene and Late Cretaceous pteropods, and their systematics reviewed. From the West Coast of North America pteropod fossils have been collected from 23 localities in Washington State, and from the Gulf Coastal Plain they have been found in 40 localities. We also review earlier published specimens from boreholes in the Atlantic Coastal Plain. As a result, six new species are introduced from the Gulf Coast (Currylimacina asperita Garvie sp. nov., Heliconoides hodgkinsoni Garvie sp. nov., Limacina texanopsis Garvie sp. nov., Limacina parvabrazensis Garvie & Janssen sp. nov., Limacina pseudopygmaea Garvie & Janssen sp. nov., Cheilospicata cedrus Garvie sp. nov.) and one from Washington State (Clio gailae Goedert & Janssen sp. nov.). The geographical distribution and/or stratigraphic ranges of several species has been extended, for example, Limacina canadaensis Hodgkinson, 1992, is reported for the first time from western North America. Some species originally described from elsewhere, Altaspiratella multispira (Curry, 1982), Heliconoides bartonensis (Curry, 1965), L. karasawai Ando, 2011, L. aff. valvatina (Reuss, 1867), Creseis spina (Reuss, 1867) and Clio chadumica Korobkov, 1966, are reported for the first time from the Americas. New specimens of several poorly known species yielded additional information on morphology or biostratigraphy. It is shown that some species have longer temporal ranges in America, occurring in, or continuing into younger deposits than those in Europe. In addition to the only Cretaceous pteropod from Washington State known so far, several enigmatic species possibly representing Pteropoda are described from the Late Cretaceous (Maastrichtian) and Danian of Texas, which allows a salient discussion on the early history of Pteropoda. An enigmatic specimen from the Eocene of Texas might represent a very early form of Gymnosomata. This analysis shows that there may be more pteropod species represented during the Late Cretaceous and Paleocene than previously suspected.
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