A new vampyromorph species from the Middle Jurassic La Voulte‐sur‐Rhône Lagerstätte

Abstract

Eight coleoid genera have so far been described from the Callovian‐aged La Voulte‐sur‐Rhône Lagerstätte (c. 165 Ma; Ardèche, France), a locality noted for its unique three‐dimensional preservation of soft tissues. Here, we used high resolution x‐ray‐based imaging methods, in conjunction with reflectance transformation imaging, to study the soft tissues of a previously undescribed coleoid from the La Voulte‐sur‐Rhône locality. This analysis identified both an ink sac and internal light organs, a combination of defence mechanisms present in the Recent, although not previously described from the coleoid fossil record, as well as the presence of Octobrachia‐type arm musculature and Vampyroteuthis‐like sucker attachments. The morphology of the gladius could not be attributed to any known coleoids and therefore justified the assignment of this single specimen to a new taxon: Vampyrofugiens atramentum. The addition of this new vampyromorph species not only increases the coleoid diversity known from the site, but also broadens the morphological variation observed in the co‐occurring coleoid taxa. These findings suggest that there was a high diversity of cephalopods occupying differentiated communities during the Middle Jurassic.

The first gladius-bearing coleoid cephalopods from the lower Toarcian “Schistes Cartons” Formation of the Causses Basin (southeastern France)

“…The latter is called gladius and consists of a sturdy but flexible chitinous structure within the dorsal mantle. The evolutionary history, anatomy and paleobiology of Mesozoic gladius-bearing coleoids has been extensively studied in the last two decades ( Fischer & Riou, 2002 ; Haas, 2002 ; Košťák, 2002 ; Fuchs, Keupp & Engeser, 2003 ; Fuchs, Engeser & Keupp, 2007a ; Fuchs, Klinghammer & Keupp, 2007b ; Fuchs et al, 2007c ; Fuchs, 2009 ; Fuchs & Iba, 2015 ; Fuchs et al, 2016 ; Bizikov, 2004 ; Bizikov, 2008 ; Fuchs & Weis, 2004 ; Fuchs & Weis, 2008 ; Fuchs & Weis, 2009 ; Fuchs & Weis, 2010 ; Wilby et al, 2004 ; Riccardi, 2005 ; Fuchs, 2006a ; Fuchs, 2006b ; Fuchs, 2006c ; Fuchs, 2007 ; Fuchs, 2009 ; Fuchs, 2015 ; Fuchs, 2016 ; Fuchs, 2019 ; Fuchs, 2020 ; Fuchs & Schultze, 2008 ; Larson, 2010 ; Donovan & Strugnell, 2010 ; Keupp et al, 2010 ; Klug, Schweigert & Dietl, 2010 ; Klug et al, 2015 ; Klug et al, 2021a ; Klug et al, 2021b ; Fuchs & Larson, 2011a ; Fuchs & Larson, 2011b ; Schlögl, Košťák & Hyžny, 2012 ; Breton, Strugnell & Donovan, 2013 ; Donovan & Boletzky, 2014 ; Fuchs & Iba, 2015 ; Jattiot et al, 2015a ; Donovan & Fuchs, 2016 ; Kruta et al, 2016 ; Marroquín, Martindale & Fuchs, 2018 ; Košťák et al, 2021 ; Moreau et al, 2022 ; Rowe et al, 2022 ; Rowe et al, 2023 ) thanks to a few localities with geological horizons particularly favourable to their preservation, the so-called Konservat-Lagerstätten. Thus, studies on exceptionally preserved Mesozoic gladius-bearing coleoids are based on...…”

“…, Wilby et al, 2004 ), the Middle Jurassic of La Voulte-sur-Rhône, France ( e.g. , Fischer & Riou, 1982 ; Fischer & Riou, 2002 ; Charbonnier, 2009 ; Kruta et al, 2016 ; Rowe et al, 2022 ; Rowe et al, 2023 ), the Upper Jurassic of Eichstätt, Solnhofen, Painten and Nusplingen Plattenkalks, Germany ( e.g. , Fuchs, 2006b ; Fuchs, 2015 ; Klug, Schweigert & Dietl, 2010 ; Klug et al, 2015 ; Keupp et al, 2010 ), the Upper Jurassic of the Causse Méjean, France ( Moreau et al, 2022 ) and the Upper Cretaceous of Hâkel, Hâdjoula and Sâhel Aalma, Lebanon ( e.g.…”

‘Arm brains’ (axial nerves) of Jurassic coleoids and the evolution of coleoid neuroanatomy

“…Preservation of nervous systems is known only from fossil localities yielding exceptional preservation. The fossil record of soft tissues is best known among octobrachians (e.g., Clements et al, 2017 ; Fuchs et al, 2010 ; Fuchs, 2006a , 2006b ; Klinghardt, 1932 ; Klug et al, 2015 ; Naef 1922 ; Rowe et al, 2022 , 2023 ). Less is known about the soft tissues of decabrachians (Fuchs et al, 2010 ; Fuchs, 2006a , 2006b ; Klug et al, 2016 , 2019 ), and less still about externally shelled (ectocochleate) cephalopods such as ammonoids and nautiloids (De Baets et al, 2013 ; Klug & Lehmann, 2015 ; Klug et al, 2012 , 2015 , 2021a , 2021c ).…”

“…Less is known about the soft tissues of decabrachians (Fuchs et al, 2010 ; Fuchs, 2006a , 2006b ; Klug et al, 2016 , 2019 ), and less still about externally shelled (ectocochleate) cephalopods such as ammonoids and nautiloids (De Baets et al, 2013 ; Klug & Lehmann, 2015 ; Klug et al, 2012 , 2015 , 2021a , 2021c ). Some of these reports (Fuchs et al, 2010 , 2021 ; Fuchs, 2006a , 2b ; Klug et al, 2016 , 2020 ; Kruta et al, 2016 ; Rowe et al, 2022 , 2023 ) demonstrated the increased preservational potential for soft tissue anatomy in the coleoid arm crown, which are typically less common than the sclerotized elements such as arm hooks or sucker rings.…”

“…In contrast to many other soft-tissue details, descriptions of the nervous system of cephalopods have only occasionally found their way into the scientific literature (Fuchs & Larson, 2011a , 2011b ; Fuchs, 2006a , 2006b ; Jattiot et al, 2015 ; Klug et al, 2016 , 2019 , 2021a ; Larson et al, 2010 ), mostly showing parts of the cephalic cartilage. Fossilized axial nerve cords that probably included the intrabrachial ganglia, the brain-like concentrations of neuronal tissues in the arms, have been documented only a few times (Kruta et al, 2016 ; Rowe et al, 2022 , 2023 ) and once unknowingly (Klug et al, 2016 , supplementary Fig. 5).…”