Fig. 4. Comparison of mandibular plates of Tithonian species within Ischyodus Egerton, 1843. All in occlusal view. A. Ischyodus quendstedti, MJSN SCR010-1000), Tithonian of Switzerland; right mandibular, mirrored for comparison (modified from Leuzinger et al. 2017). B. Ischyodus townsendi MHNC.35.444), Tithonian of central Chile; outline of the left mandibular (only visible in basal view) is overlapped in dashed lines for a better understanding of the complete plate outline. C. Ischyodus dutertrei (holotype, specimen number 3402, Musée Boulogne-sur-le-mer, France), Kimmeridgian– Tithonian of France (modified from Sauvage 1896). D. Ischyodus townsendi (holotype, BMNH P474; currently NHMUK 010039966 PV), Tithonian of England (modified from Natural History Museum, London, Data Portal, data.nhm.ac.uk, https://doi.org/10.5519/0002965). Abbreviations: act, accessory tritor; aot, anterior outer tritor; mt, median tritor; pot, posterior outer tritor; syt, symphyseal tritor.

Published as part of Otero, Rodrigo A., Bravo, Constanza Figueroa, Soto-Huenchumán, Paula, Fernández-Collemann, Sara, Valenzuela-Toro, Ana M. & Gutstein, Carolina S., 2021, First record of chimaeroid fish Ischyodus from the Upper Jurassic of southwestern Gondwana, pp. 623-630 in Acta Palaeontologica Polonica 66 (3) on page 628, DOI: 10.4202/app.00859.2020, http://zenodo.org/record/12196389