Crassescyliorhinus germanicus ( Herman, 1982 )

Adolfssen, Jan S. & Ward, David J., 2015, Neoselachians from the Danian (early Paleocene) of Denmark, Acta Palaeontologica Polonica 60 (2), pp. 313-338 : 332-333

Crassescyliorhinus germanicus ( Herman, 1982)

Fig. 9J, K .

1977 Scyliorhinus elongatus (Davis) ; Herman 1977: 252, pl. 11: 1H.

1982 Scyliorhinus germanicus sp. nov.; Herman 1982: pl. 2: 10, pl. 4: 4, 5.

1989 Scyliorhinus germanicus Herman ; Müller 1989: 47, pl. 11: 5, pl. 12: 1–4.

2001 Scyliorhinus sp. ; Cappetta in Cappetta and Odin 2001: 651, pl. 1: 8a, b.

2008 Crassescyliorhinus germanicus (Herman) ; Underwood and Ward 2008: 512, pl. 2: 10–18.

Material.—14teeth from the Ce of Stevns Kridtbrud ( MGUH 29870, GMV 2012-75 [batch number]), 10 from the Br1 at Kulstirenden ( MGUH 29871, GM2012-76 [batch number]), and one from the Br2 at Faxe ( GMV 2012-77).

Description.—Teeth displaying some monognathic and ontogenetic heterodonty. Low crowned robust teeth with a short

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massive conical main cusp and two pairs of cusplets diminishing in size from the main cusp. Anterior teeth are more symmetrical than lateral teeth. The labial face of the crown is flat with strong ornamentation in smaller teeth and less so in larger teeth. The ornamentation consists of three to six vertical folds on the main cusp bifurcating into a reticulate pattern in the basal part of the crown. The crown strongly overhangs the root and the median part of the basal edge of the crown is indented in anterior and lateral teeth. The lingual face is strongly convex and carries fine vertical or reticulated folds. Larger teeth lack most of the labial ornamentation, and posterior teeth are lower crowned and more mesio-distally elongated. The root is missing in almost all specimens. Teeth reaching a width of 3.0 mm and 2.5 mm in height.

Remarks.— Herman (1982) argued that the ornamentation of the teeth is a function of age and jaw position. This appears to be supported by the teeth sampled at Stevns Kridtbrud, as larger teeth appear to lack the labial ornamentation, whereas smaller teeth are strongly ornamented. Posterior teeth are always ornamented regardless of size.

Stratigraphic and geographic range.—Late Cretaceous: late Coniacian to early Campanian of Southern England ( Underwood and Ward 2008), middle Campanian of France ( Vullo 2005), to the late Maastrichtian of Northern Germany ( Herman 1982) and the middle Danian (early Paleocene) of Denmark.

Figures

Fig. 9. Carcharhiniformes from the Danian of Stevns Kridtbrud and Kulstirenden and Faxe kalkbrud. A–F. Palaeogaleus aff. faujasi (Geyn, 1937). A. MGUH 29872 (Ce) anterior tooth in labial (A) and lingual (A) views. B. MGUH 29873 (Ce) lateral tooth in labial (B) and lingual (B) views. 1 2 1 2 C. MGUH 29874 (Br1) posterior tooth in labial (C 1) and lingual (C 2) views. D. MGUH 29875 (Br1) anterior tooth in labial (D 1) and lingual (D 2) views. E. MGUH 29876 (Br1) anterior tooth in labial (E 1) and lingual (E 2) views. F. MGUH 29877 (Br1) lateral tooth in labial (F 1) and lingual (F 2) views. G. Triakidae sp., MGUH 29878 (Br1) tooth in labial (G 1) and lingual (G 2) views. H, I. Paratriakis curtirostris (Davis, 1887). H. MGUH 29879 (Ce) anterior tooth in labial (H ), lingual (H ), and distal (H ) views. I. MGUH 29880 (Ce) lateral tooth in labial (I ), lingual (I ), and mesial (I ) views.