Gnathophis elongatus, Agiadi & Koskeridou & Thivaiou, 2021

Agiadi, Konstantina, Koskeridou, Efterpi & Thivaiou, Danae, 2021, At the crossroads: early Miocene marine fishes of the proto-Mediterranean Sea, Fossil Record 24 (2), pp. 233-246 : 235-236

Gnathophis elongatus sp. nov.

urn:lsid:zoobank.org:act:EF4B2DCC-4246-45AB-

840E-1BC29C675410 registered on 21/7/2021

Fig. 3G–J

Holotype

Figure 3G , AMPG ( V) 2365, Aquitanian, Felli section, level 11, Grevena Prefecture, Greece; OL, 2.62; OH, 1.44; CL, 1.170; α, 12 ◦.

Paratypes

Nine specimens, AMPG ( V) 2366–74, same data as holotype .

Etymology

Due to the distinct elongated shape of its otoliths.

Diagnosis

Elongated otoliths with OL/OH of 1.60–2.06. The angle of the sulcus relative to the otolith length plane is 10–20 ◦.

Description

These otoliths are elongated with a long sulcus that forms an angle to the otolith length direction, which opens posterodorsally through a wavy ostial channel. The posterior edge is slightly protruding dorsally. The ventral rim forms an angle.

Distribution

Aquitanian of the proto-Mediterranean Basin.

Remarks

The otoliths of Gnathophis elongatus are elongated and more similar to Conger , unlike Pliocene–Holocene specimens of Gnathophis mystax that are more quadrate ( Tuset et al., 2008; Agiadi et al., 2020, 2019, 2018). However, the orientation of the sulcus forms an angle with the otolith length direction, as in Gnathophis species. The otolith figured as Gnathophis catalinensis (Wade) by Steurbaut (1984), now accepted as a synonym of Gnathophis cinctus (Garman) ( Grove and Lavenberg, 1997) , also displays the same elongate shape, distinct sulcus-to-otolith length angle as those described here. However, the sulcus is much narrower in G. elongatus , making it distinguishable from G. cinctus . Compared to G. saubriguensis (Steurbaut) , G. elongatus has a much more elongated shape, the posterodorsal edge is protruding, and the distal–ventral angle is not pointed.

Figures

Figure 3. Photographs of the identified otoliths from the Felli section. (A–D) Ariosoma mesohellenica sp. nov.: (A) holotype, AMPG(V) 2361, inner face and dorsal view; Felli 11; (B) paratype, AMPG(V) 2364, Felli 12; (C–D) paratypes, 2362 and 2363, Felli 11. (E–F) Ariosoma balearicum (Delaroche), Holocene, Israel. (G–H) Gnathophis elongatus sp. nov., Felli 11: (G) holotype, AMPG(V) 2365, inner face and ventral view; (H–J) paratypes, AMPG(V) 2366–2368. (K–L) Gnathophis saubriguensis (Steurbaut): (K) Felli 11, (L) Felli 12; (M– O) Spicara cf. gossei: (M) inner face and ventral view; Felli 11, (N–O) Felli 12. (C), (H), (K), (L), and (M) have been mirrored to facilitate comparison.