Taxonomic revision and paleoecology of Middle Devonian (Eifelian) fishes of the Onondaga, Columbus and Delaware limestones of the eastern United States

Abstract

to determine the units from which the fish specimens originally came. This method allowed reasonable inference into the provenance of the museum specimens. The stratigraphy indicates that the seas of New York and Ohio were deepening throughout the Eifelian, terminating in the dark shale beds of the Givetian stage. The rock units of both areas are characterized by a series of aggradations and inundation events. Of the 41 taxa of fish originally found in the two museums, only nine are considered valid as a result of this study. Macropetalichthys sullivanti was a benthic dweller found in the deeper units of the upper Moorehouse and Seneca members of the Onondaga Formation and the Delaware Limestone as well as the shallower units of the upper Columbus. M. rapheidolabis is considered a junior synonym of M. sullivanti. Palaeomylus and Ptyctodus were both durophagous fishes that probably stayed near the bottom of the sea. Ptyctodus was found only in the upper Moorehouse, but Palaeomylus was found in the upper Columbus, Delaware and the upper Moorehouse. Rhynchodus was found in the same units, but was a predator with shearing dentition. Deinodus bennetti was a common element of the upper Moorehouse and was a ptyctodont. It is likely, based on dental elements in the Buffalo Museum of Science, that D. bennetti was durophagous. Deinodus ohioensis, n. sp., a shallow water fish very similar to D. bennetti is formally described. Little can be theorized about its feeding strategy because most of the dental elements studied were imbedded in matrix. Onychodus and Machaeracanthus were large, mobile predators that moved in and out of deeper waters, perhaps into shallow waters to feed. Both possess large tooth whorls and elongate jaws. Machaeracanthus is formally placed in the family, Ischnacanthidae, based on these whorls and Machaeracanthus major is considered a junior synonym of M. peracutus.

An examination of the Devonian fishes of Michigan

“…obs., 2018). This type of assemblage is also found in the similarly-aged Columbus and Delaware Limestones of Ohio ( Eastman, 1907 ; Westgate & Fischer, 1933 ; Wells, 1944 ; Denison, 1978 ; Martin, 2002 ). In several formations, fishes and invertebrates are found in association within the same conglomerate or slab ( Fig.…”

“…Unfortunately, the specimen does not retain any of the diagnostic features of the genus, so we can only tentatively reattribute it ( Eastman, 1907 ; Denison, 1978 ). Whatever the case, Macropetalichthys is already known from several localities in North America, including the Delaware and Columbus Limestones of Ohio, which were closely associated with Michigan during the Middle Devonian ( Eastman, 1907 ; Denison, 1978 ; Martin, 2002 ). Arctolepis , however, is otherwise restricted to the Early Devonian of Spitsbergen ( Denison, 1978 ).…”

A large onychodontiform (Osteichthyes: Sarcopterygii) apex predator from the Eifelian-aged Dundee Formation of Ontario, Canada

“…It should be noted that the gracile morph is characterized by the type series O. sigmoides (1873), whereas the larger, more robust form is more similar to the later occurring O jandamarrai, and that the robust form may represent represent a distinct taxon. Finally, the larger Onychodus specimens from the Onondaga Formation are typically found in deeper water facies than other species which may represent a different niche occupancy for this morph (Martin 2002). These morphological observations, suggest that the genus Onychodus requires further revision.…”

“…Onychodus, the best known onychodontiform, is known from both geographically and stratigraphically widespread localities in North America, Europe, the Middle East, and Australia that span the late Early to early Late Devonian (Woodward 1888; Hairapetian et al 2000;Andrews et al 2006). The earliest occurrence of Onychodus, O. sigmoides, is from the lower Devonian strata of the Columbus (Newberry 1873;Martin 2002) and Onondaga formations (Fig. 5D-F) of Ohio and New York respectively.…”

Geospatial Analysis of Ecological Associations and Successions in Middle Devonian Bioherms of the Great Lakes Region

“…This includes species from the Columbus Formation in Marblehead, OH. List was created using previous studies by Stewart (1955), Martin (2002), Feldman (1980), andOliver (1976).…”