Harry Maisch IV

Florida Gulf Coast University | FGCU · Department of Marine & Earth Sciences

The megatooth shark, †Otodus megalodon, which likely reached at least 15 m in total length, is an iconic extinct shark represented primarily by its gigantic teeth in the Neogene fossil record. As one of the largest marine carnivores to ever exist, under�standing the biology, evolution, and extinction of †O. megalodon is important because it had a s...

The evolution of the extinct megatooth shark, Otodus megalodon, and its close phylogenetic relatives remains enigmatic. A central question persists regarding the thermophysiological origins of these large predatory sharks through geologic time, including whether O. megalodon was ectothermic or endothermic (including regional endothermy), and whethe...

The late Neogene megatooth shark, Otodus megalodon (Lamniformes: Otodontidae), is mostly known for its gigantic teeth and vertebrae. Re-examination of the rock matrix surrounding a previously described associated tooth set of O. megalodon from the upper Miocene of Japan resulted in the observation of numerous fragments of tessellated calcified cart...

Partially carbonized driftwood recovered from a lag deposit at the Arkadelphia Formation–Midway Group Contact (K–Pg) near Malvern, Arkansas contains an abundance of macrobioerosion. Macroborings are oriented perpendicular and oblique to the wood grain, straight to sinuous in shape, ≤8 cm long, may have calcitic linings, and belong to Teredolites cl...

Trophic position is a fundamental characteristic of animals, yet it is unknown in many extinct species. In this study, we ground-truth the 15N/14N ratio of enameloid-bound organic matter (δ15NEB) as a trophic level proxy by comparison to dentin collagen δ15N and apply this method to the fossil record to reconstruct the trophic level of the megatoot...

Diet is a crucial trait of an animal’s lifestyle and ecology. The trophic level of an organism indicates its functional position within an ecosystem and holds significance for its ecology and evolution. Here, we demonstrate the use of zinc isotopes (δ66Zn) to geochemically assess the trophic level in diverse extant and extinct sharks, including the...

The late Neogene megatooth shark, Otodus megalodon, is known mainly from its gigantic teeth and possibly reached 18–20 m in total length (TL). We re-examine the previously proposed body size trends and nursery areas of O. megalodon by confining the previously used samples to upper anterior teeth offering more reliable TL estimates, and by taking pa...

A lag deposit between the Tocito Sandstone and Mulatto Tongue of the Upper Cretaceous Mancos Shale in Sandoval County, New Mexico, USA, contains a fossil assemblage of late Turonian–early Coniacian chondrichthyans and osteichthyans. This assemblage consists primarily of isolated teeth that derive from at least 26 taxa including: Meristodonoides sp....

The shallow continental shelf in the Cape Fear Region of southwestern Onslow Bay, North Carolina, contains lag deposits with an abundance of megatoothed shark teeth belonging to Otodus megalodon (Agassiz 1835) and Otodus chubutensis (Ameghino 1906) that derive from the Pliocene Yorktown and Miocene Pungo River formations, respectively. These teeth...

A new species of Hypolophites (Chondrichthyes, Myliobatiformes) is described from an assemblage of isolated pavement teeth recovered from the Lower Clayton Limestone Unit of the Midway Group (Paleocene) near Malvern, Arkansas. These teeth were collected from several localized lag deposits containing an abundance of chondrichthyan and osteichthyan t...

A new species of Hypolophites (Chondrichthyes, Myliobatiformes) is described from an assemblage of isolated pavement teeth recovered from the Lower Clayton Limestone Unit of the Midway Group (Paleocene) near Malvern, Arkansas. These teeth were collected from several localized lag deposits containing an abundance of chondrichthyan and osteichthyan t...

The Lower Clayton Limestone Unit (LCLU) of the Midway Group (Paleocene) near Malvern, Arkansas, USA contains an assemblage of chondrichthyans recently exposed by excavation for highway stabilization. Chondrichthyan teeth in this assemblage belong to at least 12 taxa including: Ginglymostoma subafricanum, Carcharias cf. whitei, Carcharias sp., Odont...

The submerged continental shelf of Onslow Bay, North Carolina, preserves hardbottom limestone scarps with underlying clays as small isolated exposures in progressively deeper water seaward from the modern-day shoreline. These scarps formed as a result of wave-and current-driven erosion, transport, and redeposition of bottom sediments due to glacioe...

Glacial erratics belonging to the Rickard Hill facies (RHf) of the Saugerties Member of the Schoharie Formation (upper Emsian: Lower Devonian) occur scattered throughout the Piedmont of northern New Jersey and Lower Hudson Valley of New York. These RHf glacial erratics contain an assemblage of trilobites belonging to: Anchiopella anchiops, Burtonop...

Large fossiliferous glacial erratics occur scattered within ground moraines throughout Passaic and Bergen Counties in the northern New Jersey Piedmont. The distinct lithology and fossil assemblages identified within these glacial erratics indicates that the source provenance resides in the Lower and Middle Devonian of the Lower Hudson Valley and He...

The heteromorphic ammonite Chesapeakiceras nodatum Kennedy and Cobban, 1993, has been known only from the late Santonian to early Campanian Merchantville Formation of the Atlantic Coastal Plain of the United States. Prior to this report, only three fragmentary specimens have been recovered from the Chesapeake and Delaware Canal in the state of Dela...

The Arkadelphia Formation—Midway Group (Maastrichtian—Paleocene) contact near Malvern, Arkansas preserves a K-Pg boundary assemblage of turtle species consisting of skull, shell, and non-shell postcranial skeletal elements. The Malvern turtles are preserved within a coquina lag deposit that comprises the basalmost Midway Group and also contains an...

Glacial erratics belonging to the Rickard Hill Facies of the Saugerties Member of the Schoharie Formation (Lower Devonian Period, Upper Emsian Stage) occur scattered throughout the Piedmont of New Jersey and Lower Hudson Valley of New York. These glacial erratics contain a diverse benthic and nektonic assemblage of well-preserved invertebrate taxa...

A disconformity and lag deposit that separates the Tallahatta and Lisbon Formations along Pigeon Creek near Red Level, Conecuh-Covington Counties, Alabama, contains osteichthyan remains belonging to: Pycnodus sp.; Lepisosteus sp.; Albula sp.; Egertonia sp.; Cylindracanthus rectus Agassiz, 1843; Sphyraena sp.; Trichiurides cf. T. sagittidens Winkler...

A disconformity and lag deposit that separates the Tallahatta and Lisbon Formations along Pigeon Creek near Red Level, Conecuh-Covington Counties, Alabama contains osteichthyan remains belonging to: Pycnodus sp.; Lepisosteus sp.; Albula sp.; Egertonia isodonta Cocchi, 1864; Cylindracanthus rectus Agassiz, 1843; Sphyraena sp.; Triciurides cf. T. sag...

A lag deposit that separates the middle Eocene Squankum Member of the Shark River Formation from the early Miocene Asbury Park Member of the Kirkwood Formation near Farmingdale, Monmouth County, New Jersey, preserves an unreported chondrichthyan assemblage dominated by carcharhiniforms and lamniforms. Locally, sea level regression resulted in the e...