Sphenodus sp.

Szabó, Márton, 2017, Fish remains from the Lower Cretaceous (Valanginian-Hauterivian) of Hárskút (Hungary, Bakony Mts), Fragmenta Palaeontologica Hungarica 34, pp. 49-61 : 54

Sphenodus sp.

(Figs 9–15)

Referred material – 8 teeth (MBFSZ 2017.238.1. – MBFSZ 2017.245.1.); stratigraphic origin: Valanginian (HK-12/10) and Hauterivian (Barremian in FÜLÖP 1964) .

Description – All here referred teeth are rootless. They are slender, pointed at the tip with smooth labial and lingual face. Both the labial and lingual faces are convex, which convexity is more expressed on the lingual side. The cutting edges are sharp on both sides of the crown. Following their upright crown, convex on both faces, the best preserved specimens may represent anterior teeth (distal teeth have more flattened, distally inclined crown).

Remarks – Here I follow KLUG (2010), who included Sphenodus in Synechodontiformes . The genus represents a group of pelagic predatory neoselachians. Numerous species of Sphenodus have been described ( DUFFIN & WARD 1993), several of which have later been regarded as synonymous and/or nomina dubia (see KRIWET et al. 2006).

Only complete teeth allow a specific description ( CAPPETTA 2012). Because of their poor preservation, the torsion and height of the Hárskút cusps (important features for specific identification; see BÖTTCHER & DUFFIN 2000, Table 1 ) are not investigeable. Therefore, following the low number and poor preservation of the Hárskút orthacodontid teeth here I describe them only as Sphenodus sp. Teeth of S. nitidus , a species reported from the Upper Jurassic and the Lower Cretaceous bear a distal cutting edge developed at the tip of the cusp only ( BÖTTCHER & DUFFIN 2000, Table 1 ; see also KANNO et al. 2017, Table 1 ), which character is absent in the Hárskút specimens.

FÜLÖP (1964, pl. 17, fig. 10) illustrated specimen MBFSZ 2017.245.1. as Odontaspis sp. The general crown morphology of Sphenodus and numerous odontaspids is very similar, which may have led Fülöp to the misidentification.