“…At the site, the following ichnofossils were also described: Planolites sp., Paleophycus sp., Bergaueria sp., and Zoophycus sp., common in psamitic strata (Cruz and Soares 1996 ). Recently, Fraga and Vega ( 2020 ) described a new species of local starfish, Paranaster crucis , belonging to the class Asteroidea, Echinodermata Phylum, which has only one fossil specimen found in Paraná. The same authors also recognized the genus of sea snake Encrinaster pontis (Clarke 1913 ; Fraga and Vega 2020 ).…”
Section: Resultsmentioning
confidence: 99%
“…Recently, Fraga and Vega ( 2020 ) described a new species of local starfish, Paranaster crucis , belonging to the class Asteroidea, Echinodermata Phylum, which has only one fossil specimen found in Paraná. The same authors also recognized the genus of sea snake Encrinaster pontis (Clarke 1913 ; Fraga and Vega 2020 ). Scheffler and Fernandes ( 2007 ) identified new crinoid species at the site, Cyclocaudex paranaensis and Ophiucrinus stangeri .…”
The inventory of the geological heritage, along with the quantification of its value, is an essential task for the implementation of geoconservation strategies. Despite the Brazilian’s rich geological heritage, only the state of São Paulo has concluded its systematic inventory. This paper presents the geological heritage inventory of Paraná State and a quantitative assessment of the scientific value of geosites and their vulnerability. The method applied for the geosites evaluation was adjusted after analyzing the most deemed protocols in international literature, taking into account the Brazilian socioeconomic and cultural conditions. The selection of geosites made by experts was based on the following criteria: representativeness, rarity, integrity, and degree of scientific knowledge. The inventory consists of 76 geosites, distributed in nine geological frameworks, which represent the geological evolution of Paraná. It is expected that this work may support future planning and management actions, which can safeguard the state’s geological heritage, with efficient strategies, especially for those places with high risk of degradation.
“…At the site, the following ichnofossils were also described: Planolites sp., Paleophycus sp., Bergaueria sp., and Zoophycus sp., common in psamitic strata (Cruz and Soares 1996 ). Recently, Fraga and Vega ( 2020 ) described a new species of local starfish, Paranaster crucis , belonging to the class Asteroidea, Echinodermata Phylum, which has only one fossil specimen found in Paraná. The same authors also recognized the genus of sea snake Encrinaster pontis (Clarke 1913 ; Fraga and Vega 2020 ).…”
Section: Resultsmentioning
confidence: 99%
“…Recently, Fraga and Vega ( 2020 ) described a new species of local starfish, Paranaster crucis , belonging to the class Asteroidea, Echinodermata Phylum, which has only one fossil specimen found in Paraná. The same authors also recognized the genus of sea snake Encrinaster pontis (Clarke 1913 ; Fraga and Vega 2020 ). Scheffler and Fernandes ( 2007 ) identified new crinoid species at the site, Cyclocaudex paranaensis and Ophiucrinus stangeri .…”
The inventory of the geological heritage, along with the quantification of its value, is an essential task for the implementation of geoconservation strategies. Despite the Brazilian’s rich geological heritage, only the state of São Paulo has concluded its systematic inventory. This paper presents the geological heritage inventory of Paraná State and a quantitative assessment of the scientific value of geosites and their vulnerability. The method applied for the geosites evaluation was adjusted after analyzing the most deemed protocols in international literature, taking into account the Brazilian socioeconomic and cultural conditions. The selection of geosites made by experts was based on the following criteria: representativeness, rarity, integrity, and degree of scientific knowledge. The inventory consists of 76 geosites, distributed in nine geological frameworks, which represent the geological evolution of Paraná. It is expected that this work may support future planning and management actions, which can safeguard the state’s geological heritage, with efficient strategies, especially for those places with high risk of degradation.
“…Jell & Theron [ 51 , p. 165] synonymized Euzonosoma with Encrinaster (also [ 34 ]). They noted that Spencer [ 49 ] distinguished these genera on the basis of a single character: the mediolateral width of the adambulacrals.…”
Section: Resultsmentioning
confidence: 99%
“…Certain taxa have ambulacrals symmetrical across the midline of the arm (opposing), and phylogenetic evidence suggests that this state probably originated multiple times [ 18 ]. The morphology of the ambulacrals varies, although in many taxa, the ventral surface has been described as having a boot-shaped ridge [ 32 – 34 ]. Figure 1.…”
Living brittle stars (Echinodermata: Ophiuroidea) employ a very different locomotion strategy to that of any other metazoan: five or more arms coordinate powerful strides for rapid movement across the ocean floor. This mode of locomotion is reliant on the unique morphology and arrangement of multifaceted skeletal elements and associated muscles and other soft tissues. The skeleton of many Palaeozoic ophiuroids differs markedly from that in living forms, making it difficult to infer their mode of locomotion and, therefore, to resolve the evolutionary history of locomotion in the group. Here, we present three-dimensional digital renderings of specimens of six ophiuroid taxa from the Lower Devonian Hunsrück Slate: four displaying the arm structure typical of Palaeozoic taxa (
Encrinaster roemeri, Euzonosoma tischbeinianum, Loriolaster mirabilis, Cheiropteraster giganteus
) and two (
Furcaster palaeozoicus
,
Ophiurina lymani
) with morphologies more similar to those in living forms. The use of three-dimensional digital visualization allows the structure of the arms of specimens of these taxa to be visualized
in situ
in the round, to our knowledge for the first time. The lack of joint interfaces necessary for musculoskeletally-driven locomotion supports the interpretation that taxa with offset ambulacrals would not be able to conduct this form of locomotion, and probably used podial walking. This approach promises new insights into the phylogeny, functional morphology and ecological role of Palaeozoic brittle stars.
“…Many asteroids, ophiuroids, and stylophorans from this unit have been preserved at the base of thin muddy beds, only about 1–3 cm thick. Most specimens are articulated and present resting and walking postures, indicating abruptly buried living assemblages (Fraga & Vega 2020, 2022). The absence of escape postures under such thin beds draws attention to a potential mass numbness during burial, blocking attempts to excavate the sediment.…”
This research explores the significance of rapid burial in preserving fossils, with a particular focus on free‐living echinoderms. Experiments were based on ophiuroids to simulate burial under different turbiditic flows. The results showed that a bed thickness of around 10 cm is a limit for the preservation of whole skeletons in most cases. The type of sediment can affect the integrity of the buried skeletons, with sand deposition resulting in higher rates of autotomy. However, mud deposition did not show any numbing effect, as previously believed for echinoderms. In contrast, freshwater‐rich sediments can play a critical role, paralysing specimens and preventing escape postures through rapid changes in salinity. From this, the study highlights the importance of extrabasinal turbidites, generated outside the marine basin, in the fossilization of marine invertebrates. Such sediments are rich in fresh water and can be more efficient burial traps compared to other intrabasinal deposits generated by storm waves or submarine landslides.
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