Pachydiscus (Pachydiscus) neubergicus neubergicus (Hauer, 1858)

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 : 9-15

Pachydiscus (Pachydiscus) neubergicus neubergicus (Hauer, 1858)

Figure 4U–W

Ammonites neubergicus Hauer, 1858: 12 , pl. 2, figs. 1–3, non pl. 3, figs. 1, 2.

Pachydiscus (Pachydiscus) neubergicus (von Hauer, 1858) , Kennedy and Summesberger, 1986: 189, pl. 2, figs. 1, 2, pl. 3, figs. 1–3, pl. 4, figs. 1–5, pl. 5, figs. 1, 4, 5, pl. 6, figs. 1, 2, 5, pl. 15, figs. 7, 8, text­figs. 5a, b (with full synonymy).

Pachydiscus (Pachydiscus) neubergicus (Hauer, 1858) , Kennedy, 1986b: 34, pl. 4, fig. 3.

? Pachydiscus (Pachydiscus) cf. neubergicus (Hauer, 1858) , Vasicek, 1988: 76, pl. 1, fig. 3.

Pachydiscus (Pachydiscus) neubergicus neubergicus (Hauer, 1858) , Kennedy and Henderson, 1992: 420, pl. 10, figs. 6–8, pl. 11, text­fig. 6A (with additional synonymy).

Pachydiscus (Pachydiscus) neubergicus (Hauer, 1858) , Hancock and Kennedy, 1993: 158, pl. 3, figs. 6, 7, pl. 9, figs. 5–8, pl. 12, figs. 7–9, pl. 13, figs. 5–7.

Pachydiscus (Pachydiscus) neubergicus neubergicus (Hauer, 1858) , Ward and Kennedy, 1993: 30, figs. 25.9–25.12, 25.14, 25.16–25.18, 27.3– 27.5, 27.7, 28.1–28.3, 30.4, 30.6.

Pachydiscus (Pachydiscus) neubergicus (Hauer, 1855) , Kennedy et al., 1995: pl. 6, figs. 16, 17.

LECTOTYPE: The lectotype is No. 1858.01. 6 in the collections of the Geologische Bundesanstalt, Vienna, the original of Hauer, 1858 (pl. 2, figs. 1–3), designated by de Grossouvre, 1894 (p. 209; see Kennedy and Summesberger, 1986: pl. 3, figs. 1–3). It is from the lower Maastrichtian of Neuberg , Steiermark, Austria.

DESCRIPTION: MAPS A2045a2 (not illustrated, plaster cast USNM 445245) has a whorl height of 19.5 mm. The ratio of whorl breadth to whorl height is 0.9. The umbilical shoulder is narrowly rounded. The inner flanks are broadly rounded, the outer flanks are convergent, and the venter is broadly rounded. Three distant umbilical bullae give rise to narrow, prorsiradiate ribs that weaken on the middle of the flanks but strengthen on the outer flanks. Several intercalated ribs are present between the primaries; they arise on the middle to outer flanks, so that there are 14 ventral ribs corresponding to the three bullae; these ribs strengthen over the venter, which they cross in a broad convexity.

MAPS A2045a1 (fig. 4U–W, plaster cast USNM 445424) is a much larger fragment, wholly septate to a whorl height of 50 mm. The whorl section is compressed with a ratio of whorl breadth to whorl height of 0.8, with the greatest breadth at the umbilical shoul­ der. The umbilicus is moderately deep, the umbilical wall is flattened and inclined outward, and the umbilical shoulder is rounded. The inner flanks are broadly rounded, the outer flanks are flattened and convergent, and the ventrolateral shoulders are broadly rounded. The venter is quite broad and flattened. Six umbilical bullae are present in the 150° sector preserved; they are strong, feebly concave, and give rise to prorsiradiate ribs that weaken across the middle of the flanks. Pairs of intercalated ribs arise on the outer flanks, and all ribs strengthen markedly across the venter. The suture is imperfectly preserved, but is intricately subdivid­ ed and typical for the genus.

DISCUSSION: Cobban (1974a: 18, pl. 11, figs. 5–8, text­fig. 15) recorded juvenile Pachydiscus sp. from the Navesink Formation at Atlantic Highlands, which Błaszkiewicz (in Cobban, 1974a: 18) considered to be most similar to P. (P.) neubergicus . The larger fragment illustrated here confirms this view and demonstrates beyond doubt the presence of this important Maastrichtian marker species in the eastern United States. Kennedy and Summesberger (1986) provided a full description and synonymy of this species, and illustrated the lectotype and topotype material. Differences between P. (P.) neubergicus neubergicus and subspecies P. (P.) neubergicus dissitus Henderson and McNamara, 1985 (p. 72, pl. 7, figs. 7, 9, pl. 10, figs. 3–6, text­figs. 11, 12c, 13c) are fully described by these authors.

OCCURRENCE: The Navesink specimens are from the lower phosphatic layer at Atlantic Highlands, New Jersey. The species is typically lower Maastrichtian in Europe, but ranges up into the lower part of the upper Maastrichtian Belemnitella junior belemnite zone. It is known from Denmark, north Germany, Austria, Czechoslovakia, Russia, southwestern France, northeastern Spain, Nigeria, southern India, Zululand ( South Africa), and Madagascar, with subspecies dissitus in the upper Maastrichtian of western Australia.

SUBORDER ANCYLOCERATINA WIEDMANN, 1966

SUPERFAMILY TURRILITACEAE GILL, 1871

FAMILY NOSTOCERATIDAE Hyatt, 1894

Genus and Subgenus Nostoceras Hyatt, 1894

TYPE SPECIES: Nostoceras stantoni Hyatt, 1894, p. 569 ; by original designation = Ancyloceras? approximans Conrad, 1855, p. 266 .

Nostoceras (Nostoceras) approximans (Conrad, 1855) Figures 4S, T, 5A–E, K–O

Ancyloceras approximans Conrad, 1855: 266 .

Ancyloceras approximans Conrad, Conrad, 1860 : pl. 47, fig. 4.

Nostoceras stantoni Hyatt, 1894: 570 .

Nostoceras stantoni aberrans Hyatt, 1894: 572 .

Nostoceras stantoni retrorsum Hyatt, 1894: 579 .

Nostoceras stantoni prematurum Hyatt, 1894: 572 .

Nostoceras stantoni Hyatt, Roman, 1938: 445 .

Nostoceras stantoni Hyatt, Stephenson, 1941: 407 , pl. 80, figs. 1–5.

Nostoceras stantoni aberrans Hyatt, Stephenson, 1941: 409 , pl. 80, figs. 9, 10.

Nostoceras stantoni retrorsum Hyatt, 1894 , Stephenson, 1941: 408.

Nostoceras stantoni prematurum Hyatt, Stephenson, 1941: 409 , pl. 80, figs. 6–8. non Nostoceras spec. aff. stantoni aberrans Hyatt, Bürgl, 1955: 43, pl. 6, fig. 12.

non Nostoceras spec. aff. stantoni aberrans, Hyatt, Bürgl, 1957: pl. 17, fig. 3.

non Nostoceras stantoni serratum Collignon, 1971: 12 , pl. 644, fig. 2383.

Nostoceras cf. N. stantoni Hyatt, Cobban, 1974a: 12 , pl. 9, figs. 23–31, text­fig. 9.

? Nostoceras sp. cf. N. stantoni Hyatt, Matsumoto, 1977: 323 , pl. 61, fig. 3.

Nostoceras (Nostoceras) approximans (Conrad, 1855) , Kennedy et al., 1995: pl. 6, figs. 9–12.

HOLOTYPE: The holotype is the original of Conrad (1855: 266), by monotypy. It is ANSP 12861 , and was said to be from White River, Arkansas.

DISCUSSION: Cobban (1974a) had only helices of this species for his original account of the Navesink fauna. Subsequent collecting has produced adult body chambers that correspond to the holotype of Nostoceras (N.) approximans and to N. (N.) stantoni Hyatt, 1894 (Stephenson, 1941: 407, pl. 80, figs. 1– 5), which is treated as a junior synonym. Figured microconchs include the holotype, ANSP 12861 (fig. 5C–E) and MAPS A2027a1 (fig. 5K–M). One specimen, USNM 445246, has suffered an injury in life, and, as a result, one of its rows of tubercles is greatly reduced (fig. 5N, O). An adult macroconch body chamber ( MAPS A2027a2) is illustrated as figure 5A, B.

OCCURRENCE: Upper Campanian; lower phosphatic layer, basal part of Navesink Formation, Atlantic Highlands, New Jersey; Nacatoch Sand of northeast Texas; Saratoga Chalk of Arkansas; Baculites jenseni zone in the Pierre Shale of Colorado. Records from Colombia and Madagascar belong to other species; that from Japan is doubtful.

Nostoceras (Nostoceras) hyatti Stephenson, 1941 Figures 6 , 7G–I

Nostoceras hyatti Stephenson, 1941: 410 , pl. 81, figs. 9–12.

Nostoceras hyatti Stephenson, Cobban, 1974a: 10 , pl. 5, figs. 1–21, pl. 6, figs. 1–12, pl. 7, figs. 1– 10, pl. 8, figs. 1–30, text­fig. 8 (with full synonymy).

Nostoceras (Nostoceras) pozaryskii Błaszkiewicz, 1980: 26 (part), pl. 10, figs. 8, 9, 12 only.

Nostoceras (Nostoceras) hyatti Stephenson, 1941 , Kennedy, 1986a: 90, pl. 20, figs. 7–9.

Nostoceras (Nostoceras) hyatti Stephenson, 1941 , Kennedy and Cobban, 1993: 417, figs. 9.2, 11.1–11.27.

Nostoceras (Nostoceras) hyatti Stephenson, 1941 , Ward and Kennedy, 1993: 14, fig. 15.1, 15.2.

Nostoceras (Nostoceras) hyatti Stephenson, 1941 , Hancock and Kennedy, 1993: 162, pl. 9, figs. 1–4, pl. 14, figs. 2–4, pl. 16, figs. 2, 3, pl. 17, figs. 10, 11, pl. 18, figs. 2–4, 6, 7, pl. 19, figs. 1–4, 8–10.

Nostoceras (Nostoceras) hyatti Stephenson, 1941 , Kennedy et al., 1995: pl. 6, figs. 7, 8, pl. 7, figs. 9, 10.

TYPES: The holotype is USNM 77258 , the original of Stephenson, 1941: pl. 81, fig. 9, from the Nacatoch Sand on Postoak Creek at the north edge of Corsicana , Navarro County, Texas. There are four paratypes .

DISCUSSION: We have examined more than 100 specimens in addition to those described by Cobban (1974a). These show marked size dimorphism as demonstrated by figure 6A– C, a microconch, and figure 6D–F and figure 7G–I, two macroconchs, the latter pathological. Kennedy was also able to examine the type specimens and topotypes of Nostoceras pozaryskii Błaszkiewicz, 1980 , and is convinced that this species is in part based on specimens of N. (N.) hyatti , notably the original of Błaszkiewicz, pl. 10, figs. 8, 9, 12. The holotype (Błaszkiewicz, 1980: pl. 10, figs. 1–5) is a specimen of N. (N.) helicinum, as are the originals of his pl. 10, figs. 6, 7, 10, 11, 13–15.

OCCURRENCE: Upper Campanian; lower phosphatic layer, basal part of Navesink Formation, Atlantic Highlands, New Jersey; Nacatoch Sand of northeast Texas; Coon Creek Tongue of Ripley Formation in Tennessee; Saratoga Chalk in Arkansas; Angola?; Israel; Tercis, Landes, France; Maurens, Aquitaine, France; and the Vistula Valley, Poland.

Nostoceras (Nostoceras) alternatum (Tuomey, 1854) Figure 4L–O

Turrulites alternatns (sic) Tuomey, 1854: 168.

Turrilites spinifera Conrad, 1860: 284 .

Turrilites spinifera Conrad, Gabb, 1861b: 92 .

Turrilites alternatus Tuomey, Gabb, 1861b: 91 .

Nostoceras alternatum (Tuomey) , Cobban, 1974b: 86, figs. 1w–rr, 5.

Nostoceras (Nostoceras) alternatum (Tuomey, 1854) , Cobban and Kennedy, 1991: E3, pl. 2, figs. 5–27.

Nostoceras (Nostoceras) alternatum (Tuomey, 1854) , Cobban and Kennedy, 1995: 14, figs 9.10, 9.11.

TYPES: The types were from Noxubee County, Mississippi, but are lost .

DESCRIPTION: MAPS A2041a1 (fig. 4L, M) is a septate fragment 21 mm long with a maximum preserved whorl height of 11.5 mm. It has a concave upper whorl face and an outer whorl face that is broadly rounded above and flattened below. The juncture of the outer and lower whorl faces is narrowly rounded; the lower whorl face is flattened. Twelve narrow ribs are straight and transverse to slightly concave and prorsiradiate on the outer whorl face. Six strong, transversely elongate tubercles are present at the juncture of the outer and lower whorl faces. Each tubercle is linked to a single rib or a pair of ribs and gives rise to one or two distant, narrow, feebly convex ribs on the lower whorl face. These ribs either link singly or zig­zag in pairs to transversely elongated tubercles at the margin of the umbilicus. The suture is moderately incised with broad, bifid saddles.

NJSM 17737 (fig. 4N, O) is a water­worn fragment of a body chamber (no sutures are visible) 23.5 mm long with a maximum preserved height of 11.0 mm. There are seven tubercles at the juncture of the outer and low­ er whorl faces.

DISCUSSION: The distribution of tubercles, with one row at the juncture of the outer and lower whorl faces, and the other close to the umbilicus on the base of the whorl, immediately distinguishes this species from all other representatives of the genus.

OCCURRENCE: Lower Maastrichtian; float, presumably from basal 3 m of Navesink Formation, Big Brook , near Marlboro , New Jersey ; Coon Creek Tongue of Ripley Formation in Mississippi , and correlatives in Alabama and Georgia; and Nacatoch Sand in Arkansas .

Nostoceras (Nostoceras) pauper (Whitfield, 1892) Figure 8A–H

Turrilites pauper Whitfield, 1892: 268 , pl. 45, figs. 1–5.

Turrilites pauper Whitfield, Weller, 1907: 834 , pl. 108, figs. 1–4.

Turrilites pauper Whitfield, Grabau and Shimer, 1910: 211 , figs. 1484, 1485.

Nostoceras pauper (Whitfield) , Cobban, 1974a: 12, pl. 9, figs. 1–22, text fig. 10.

Nostoceras (Nostoceras) pauper (Whitfield, 1892) , Kennedy and Cobban, 1993: 420, fig. 7.5–7.7, 7.16–7.18, 7.24.

HOLOTYPE: The holotype, by monotypy, is NJSM 7659 from the Navesink Formation, New Jersey, the original of Whitfield , 1892: pl. 45, figs. 1–5.

DISCUSSION: Several additional specimens supplement those already described by Cobban (1947a). New specimens include both the spiral portions of the shell (fig. 8A–F) and the uncoiled body chamber (fig. 8G, H). They are all characterized by coarse ribs and two rows of tubercles, one at mid­flank and the other at the base of the outer whorl face. Differences between Nostoceras (N.) pauper and other species of the genus are discussed by Kennedy and Cobban (1993).

OCCURRENCE: Upper Campanian; lower phosphatic layer of Navesink Formation, Atlantic Highlands ; float, presumably from basal Navesink Formation, Ramanessin Brook, Holmdel: and Big Brook, Marlboro , Monmouth County, New Jersey . Outside New Jersey , this species is known from the basal Saratoga Chalk , southwestern Arkansas .

Figures

Fig. 5. A–E, K–O. Nostoceras (Nostoceras) approximans (Conrad, 1855). A, B. MAPS A2027a2, macroconch; C–E. holotype, ANSP 12861, microconch, White River, Arkansas; K–M. MAPS 2027a1, microconch; N, O. USNM 445246, pathological microconch. F–H. Exiteloceras rude, n. sp., holotype, USNM 433778, Big Brook, near Marlboro, Monmouth County. I, J. Didymoceras cf. D. draconis (Stephenson, 1941), MAPS A2040b1. All specimens are from the lower phosphatic layer, Navesink Formation, Atlantic Highlands, New Jersey, unless otherwise stated. All figures are X1.

Fig. 6. Nostoceras (Nostoceras) hyatti Stephenson, 1941. A–C. MAPS A2004a1, microconch; D– F. MAPS A2004a2, macroconch. All specimens are from the lower phosphatic layer, Navesink Formation, Atlantic Highlands, New Jersey. All figures are X1.

Fig. 7. A–F. Baculites sp. A–C. NJSM 13439; D–F. NJSM 12931. Both specimens are from the Navesink Formation, Inversand Pit, Sewell, Gloucester County, New Jersey. G–I. Nostoceras (Nostoceras) hyatti Stephenson, 1941, MAPS A2004a3, pathological macroconch with only one row of ventral tubercles, lower phosphatic layer, Navesink Formation, Atlantic Highlands, New Jersey. All figures are X1.