Spondyliosoma tingitana, Schwarzhans, 2023

Spondyliosoma tingitana n. sp.

Figure 27b–c View Fig

Holotype SMF PO 101.293 ( Fig. 27c View Fig ), Dar bel Hamri, coquina at river level of Oued Beth, Zanclean.

Paratype 4 specimens SMF PO 101.294 , same data as holotype .

Etymology From “Mauretania tingitana” (Latin) = the Roman name for the northwestern Moroccan region, deduced from Tingis (Latin), the ancient name of Tanger.

Diagnosis OL:OH = 1.75 to approximately 2.0. Ventral rim very shallow, regularly curved; dorsal rim with low predorsal and distinct postdorsal angle; posterior rim slanted, concave. Rostrum relatively short, 15% OL. CaL:OsL = 1.6. Curvature of caudal tip 45–55°, terminating moderately close to postventral rim.

Description Moderately large, elongate and thin otoliths up to at least 8 mm in length judging from the incomplete specimen of Fig. 27b View Fig (holotype 5.7 mm). OH:OT = 3.4– 3.7. Ventral rim shallow, regularly curved, smooth; dorsal rim with low predorsal angle, more pronounced postdorsal angle, slightly to irregularly undulating. Rostrum relatively short (completely preserved only in specimens of Fig. 27c View Fig ); no antirostrum or excisura. Posterior rim slanted, concave below postdorsal angle, with rounded or projecting inferior tip.

Inner face slightly convex with distinctly supramedian positioned, moderately deep, long sulcus. Ostium short, wide. Cauda long, anteriorly straight, its tip bend downward at 45 to 55°; caudal tip tapering or rounded, terminating moderately close to postventral otolith rim. Dorsal depression narrow, short, ventrally marked by crista superior, dorsal margin indistinct; ventral field with feeble ventral furrow close to ventral rim of otolith. Outer face distinctly concave, relatively smooth.

Discussion Te genus Spondyliosoma contains two species today, S. cantharus (Linnaeus, 1758) in the Mediterranean and northeast Atlantic from the British Isles to Namibia ( Froese & Pauly, 2022; for extant otoliths see Lombarte et al., 2006 and Nolf et al., 2009) and S. emarginatum (Valenciennes, 1830) in the southwestern Indian Ocean along the shores of South Africa and Madagascar ( Froese & Pauly, 2022; for extant otoliths see Smale et al. 1995). Spondyliosoma tingitana resembles the otoliths of both extant species, but differ in the relatively strongly developed postdorsal angle, concave posterior rim and in being less strongly bent.