This list of fossil fish described in 2018 is a list of new taxa of jawless vertebrates, placoderms, acanthodians, fossil cartilaginous fish, bony fish, and other fish of every kind that are scheduled to be described during the year 2018, as well as other significant discoveries and events related to paleontology of fish that are scheduled to occur in 2018.
Research
A study on the fossil fish occurrences and habitat during the middle Paleozoic (480 million to 360 million years ago) is published by Sallan et al. (2018), WHAT WAS THE BIOPIC FOR TYRANOSUARUS FOR THE EPIC MOMENT. fish originated in restricted, shallow intertidal-subtidal environments. A survey of Devonian fish fauna from Michigan is published by Stack & Sallan (2018). A study on the ecological diversification of thelodonts is published by Ferrón et al. (2018). The first occurrence of pelvic girdles and intromittent organs in Euphanerops longaevus, associated with a morphologically differentiated region of the axial skeleton, is reported by Chevrinais et al. (2018). A study on the identity of the aspidin (a primitive bone-like tissue of heterostracans) is published by Keating et al. (2018), who interpret aspidin as an acellular dermal bone. Redescription of Tesseraspis mosaica is published by Blieck, Elliott & Karatajūtė-Talimaa (2018). A study on the morphological and taxonomic diversity of pteraspidiforms is published by Romano, Sansom & Randle (2018). A study on the diversity of jaw shapes in modern and Paleozoic jawed fishes, evaluating whether the full extent of jaw morphological variation was established early in gnathostome evolutionary history, is published by Hill et al. (2018). New specimens of Brindabellaspis stensioi, providing new information on the morphology of the rostral region of the skull, are described from the Lower Devonian of the New South Wales (Australia) by King, Young & Long (2018). Redescription of the antiarch placoderm Asterolepis thule and a study on the age of the deposits preserving the fossils of this species is published by Newman & Den Blaauwen (2018). Description of bony pelvic plates in 32 specimens of Bothriolepis canadensis from the Upper Devonian Escuminac Formation (Canada) is published by Charest, Johanson & Cloutier (2018), who reject the interpretation of these structures as genital plates (suggested by Long et al., 2015), and identify them as the pelvic girdle instead. Redescription of the antiarch placoderm Phymolepis cuifengshanensis and a study on the phylogenetic relationships of this species is published by Wang & Zhu (2018). A study on the morphology of the skull, especially the braincase of the petalichthyid placoderm Shearsbyaspis oepiki is published by Castiello & Brazeau (2018). Fossil interpreted as placoderm (arthrodiran) egg cases are described from the Devonian (Famennian) Cleveland Shale (Ohio, United States) by Carr & Jackson (2018). Circular or near-circular patterned trace fossils, similar to underwater circles produced by male pufferfishes, are described from the Upper Devonian Hongguleleng Formation (China) by Zong & Gong (2018), who consider it possible that these fossils may be structures made by male fish to attract females. Redescription of Gladbachus adentatus and a study on the phylogenetic relationships of the species is published by Coates et al. (2018). A study on the wear of a tooth whorl of a specimen of Edestus heinrichi, as well as on its implications for inferring the function of the tooth whorls in this species, is published by Itano (2018). New description of Edestus, providing new information on the anatomy of this taxon, is published online by Tapanila et al. (2018). Two partial specimens of a callorhynchid chimaeroid left in open nomenclature are described from the Upper Kimmeridgian Nusplingen Plattenkalk (Germany) by Duffin (2018). A study on the teeth histology and vasculature of the oldest known tooth-bearing sharks, Leonodus carlsi and Celtiberina maderi, is published by Martinez-Perez et al. (2018). The first known basicranium of Carcharopsis wortheni is described from the Carboniferous Fayetteville Shale (United States) by Bronson, Mapes & Maisey (2018). A study on the morphology of the braincase of Tristychius arcuatus is published by Coates & Tietjen (2018). A diverse fauna of Early Triassic cartilaginous fishes is described from the Vikinghøgda Formation (Spitsbergen, Norway) by Bratvold, Delsett & Hurum (2018). The first material referable to hybodont shark (a member of the genus Asteracanthus) is described from the Lower Jurassic (Toarcian) Rosso Ammonitico Formation (Italy) by Romano et al. (2018), providing new information on the dispersal of this genus in the Jurassic Tethys.