Ambocoelia gregaria, Hall, 1867

Day, Jed & Over, D. Jeffrey, 2002, Post-extinction survivor fauna from the lowermost Famennian of eastern North America, Acta Palaeontologica Polonica 47 (2), pp. 189-202 : 198

Ambocoelia cf. A. gregaria Hall, 1867

Fig. 4J .

Ambocoelia umbonata var. gregaria ; Hall 1867: 195, pl. 44: 19–25.

Ambocoelia gregaria ; Linsley 1994: 104, 233, pl. 126: 1–7.

Material.—Figured specimen NYSM 15719, crushed specimen of ventral valve shown in the upper left part of Fig. 5D , three additional specimens on same slab as aforementioned specimens (two ventral, one dorsal valve).

Remarks.—The dorsal valve shown in Fig. 5J ( NYSM 15719) is comparable to Hall’s (1867) dorsal valve illustrated on his pl. 44 (fig. 19). The two unnumbered specimens of ventral valves have a ventral sinus originating near the beak as seen Hall’s (1867: pl. 44: 19–25) A. gregaria . Additional material isrequiredtoconfirmthisprovisionalspeciesidentification.

Figures

Fig. 4. Brachiopods from the shell bed in the Hanover Shale Member of the Java Formation. A–D. Retichonetes aff. S. obscurus Cooper and Dutro, 1982. A. Internal mold of dorsal valve, NYSM 15704 with low medial myophragm, simple sockets flanking the pit near base of cardinal process, × 5.4. B. Upper exteriorviewofdorsalvalve,NYSM15710,×4.8. C.Internalmoldofdorsalvalve,NYSM15705,×7. D.Ventralvalveshowingcostellaewithcrushedand distorted ventral valve of Ambocoelia cf. A. gregaria in upper left, NYSM 15718, × 3.3. E. Tylothyris mesacostalis (Hall, 1867), view of dorsal valve showing centric lamellose ornament and central groove on fold, NYSM 15711, × 2.3. F, G. Praewaagenoconcha speciosa (Hall, 1867). F. Internal mold of dorsal valve with impression of medial myophragm and rugae along the postero−lateral margin, NYSM 15706, × 1.7. G. External mold of dorsal valve showing radial spine bases with some exfoliated shell material, NYSM 15695, × 1.5. H, I. Cyrtospirifer hornellensis Greiner, 1957. H. Exfoliated dorsal valve showing extended postero−lateral extremity, NYSM 15692. I. Ventral valve, NYSM 15691; both × 1.8.J. Ambocoelia cf. A. gregaria Hall, 1867, upper view of flattened dorsal valve showing dorsal groove, NYSM 15719 × 3.5.

Fig. 5. Digital images from scanning electron microscope of conodont P1 (Pa) elements from the Hanover Shale Member of the Java Formation, brachiopod bed approximately 1.4 m above the Frasnian–Famennian boundary at Glade Creek, Bartz Road, Wyoming County, New York. All × 60. A–C. Palmatolepis triangularis Sannemann, 1955. A, B. Lower view and inverse mirror−image of mold of upper surface of P1 (Pa) element, NYSM 15682. C. Inverse mirror−image of mold of upper surface of P1 (Pa) element, NYSM 15683. D–F. Icriodus alternatus alternatus Branson and Mehl, 1934. D, E. Upper and oblique outer views of broken P1 (Pa, I) element showing internal mold of posterior end, NYSM 15684. F. Upper view of P1 (Pa, I) element with missing inner posterior margin, NYSM 15685. G. Icriodus alternatus helmsi Sandberg and Dreesen, 1984, upper view of fractured and covered P1 (Pa, I) element, NYSM 15686 (specimen lost).