Discoscaphites Meek, 1870

KENNEDY, W. J., LANDMAN, N. H., COBBAN, W. A. & JOHNSON, R. O., 2000, Additions to the Ammonite Fauna of the Upper Cretaceous Navesink Formation of New Jersey, American Museum Novitates 3306, pp. 1-31 : 26

Genus Discoscaphites Meek, 1870

TYPE SPECIES: Ammonites Conradi Morton, 1834 (p. 39, pl. 16, fig. 3, by original designation) .

Discoscaphites gulosus (Morton, 1834)

Figure 9G–I

Ammonites Conradi var. (A) gulosus Morton, 1834: 39 , pl. 16, fig. 2.

Scaphites gulosus (Morton) , Owen, 1852: 578.

Scaphites (Discoscaphites) conradi var. gulosus (Morton) , Meek, 1876: 432, pl. 36, fig. 1.

Discoscaphites conradi var. gulosus (Morton) , Reeside, 1927: 29.

Discoscaphites gulosus (Morton) , Landman and Waage, 1993: 212, figs. 156, 157, 159, 160, 167–180 (with full synonymy).

Discoscaphites gulosus (Morton, 1834) , Cobban and Kennedy, 1995: 29, figs. 10.4, 10.5, 19.20– 19.24, 20.2, 20.8–20.12, 20.14–20.17, 21.18– 21.21.

TYPE: The holotype is ANSP 51552 , from the Prairie Bluff Chalk at Prairie Bluff , Alabama .

DESCRIPTION: NJSM 16121 (fig. 9G–I) is most of a stout adult body chamber 42.0 mm long with a whorl height of 20.4 mm. Only one side is preserved. The flank is flattened and the venter is broadly rounded. The ornament comprises five equally spaced rows of small, round tubercles located on low, poorly defined, very weak ribs.

DISCUSSION: This specimen is part of a small macroconch that resembles those illustrated by Landman and Waage (1993) from the Fox Hills Formation of South Dakota.

OCCURRENCE: This specimen was collected from a spoil pile of the Navesink Formation at the Inversand Pit at Sewell, Gloucester County, New Jersey. It could be from a lag deposit above the Navesink Formation, but its state of preservation is characteristic of Navesink fossils. The species is known elsewhere from the Upper Maastrichtian Severn Formation in Maryland, the Prairie Bluff Chalk in Alabama, the Corsicana Formation in Texas, and the Hoploscaphites nicolletii and Jeletzkytes nebrascensis zones of the Fox Hills Formation in South Dakota.

Figures

Fig. 9. A–F. Hoploscaphites pumilus (Stephenson, 1941). A, B. MAPS 2032a1; C, D. MAPS 2032a2; E, F. MAPS 2032a3; G–I. Discoscaphites gulosus (Morton, 1834), NJSM 16121, Inversand Pit, Sewell, Gloucester County, New Jersey. J–P. Jeletzkytes cf. J. nodosus (Owen, 1852). J–L. MAPS A2020a3; M, N. MAPS A2020a5; O, P. MAPS A2020a4. All specimens are from the lower phosphatic layer, Navesink Formation, Atlantic Highlands, unless otherwise stated. All figures are X1.