Leptoelops rhenanus (Weiler, 1954)

Schwarzhans, Werner & Keupp, Helmut, 2022, Early teleost otolith morphogenesis observed in the Jurassic of Franconia, Bavaria, southern Germany, Zitteliana 96, pp. 51-67 : 51

Leptoelops rhenanus (Weiler, 1954)

Plate 3, figs 14-16

Otolithus rhenanus 1954 Otolithus ( Lycopteridarum ?) Otolithus rhenanus - Weiler: pl. 1, fig. 18.

Otolithus rectisulcatus 1956 Otolithus rectisulcatus - Schröder: pl. 6, fig. 21.

Otolithus scissus ?1956 Otolithus scissus - Schröder: pl. 7, figs 29-30.

Leptoelops rhenanus 2018 Leptoelops rhenanus (Weiler, 1954) - Schwarzhans: fig. 5O.

Material.

5 specimens: Weiler’s holotype of Ot. rhenanus from the Callovian of well Bruchsal D 205 (core from 482 to 487 m) near Weingarten, Baden-Würtemberg (SMF P.2953, refigured in Plate 3 , fig. 14) ; 4 specimens from Schröder’s collection from the early Callovian of Pünzendorf: holotype of Ot. rectisulcatus (SNSB-BSPG 2022 III 37, Plate 3 , fig. 15) and 1 paratype (SNSB-BSPG 2022 III 38), holotype of Ot. scissus (SNSB-BSPG 2022 III 40, Plate 3 , fig. 16) and 1 paratype (SNSB-BSPG 2022 III 41).

Diagnosis

(from Schwarzhans 2018). Thin, elongate otolith with an OL:OH ratio of 2.1. Rostrum about 40% of OL. Ostium dorsally open, its ventral margin level with the ventral margin of its cauda. Outer face with radial furrows near ventral rim.

Discussion.

Leptoelops rhenanus is a very characteristic otolith that differs readily from Leptolepis otoliths in both its very slender shape and its absence of a ventrally widened ostium. Schröder’s holotype of Ot. rectisulcatus lacks the rostrum, but otherwise it largely resembles Weiler’s holotype of L. rhenanus . The specimens of Ot. scissus are also fragmentary, less well-preserved, and much smaller in size. They differ somewhat in the posteriorly elevated dorsal rim and a slight bend in the cauda. We consider these features aspects of an ontogenetical allometry, but we are aware that they could also indicate the presence of another species in the Callovian. We have therefore only tentatively attributed Ot. scissus to L. rhenanus , subject to finding additional and better-preserved specimens in the future.

Figures

Plate 3. Otoliths of Leptolepis kremmeldorfensis, L. inaequalis, L. macrocephalus, and Leptoelops rhenanus. figs 1 - 6: Leptolepis kremmeldorfensis (Schroeder, 1956); 1: holotype of Ot. kremmeldorfensis Schroeder, 1956 from Kremmeldorf (SNSB-BSPG 2022 III 35); 2: paratype of Ot. kremmeldorfensis Schroeder, 1956 from Kremmeldorf (SNSB-BSPG 2022 III 36); 3: holotype of Ot. amygdalinus Schroeder, 1956 from Kremmeldorf (SNSB-BSPG 2022 III 14); 4: paratype of Ot. bambergensis Schroeder, 1956 from Freiahorn (SNSB-BSPG 2022 III 10); 5: holotype of Ot. franconicus Schroeder, 1956 from Kremmeldorf (SNSB-BSPG 2022 III 24); 6: paratype of Ot. franconicus Schroeder, 1956 from Kremmeldorf (SNSB-BSPG 2022 III 27). figs 7, 8: Leptolepis cf. kremmeldorfensis (Schroeder, 1956), from the late Pliensbachian of Buttenheim, SNSB-BSPG 2022 IV 15. figs 9 - 11: Leptolepis inaequalis (Weiler, 1954); 9: holotype of Ot. puenzendorfensis Schroeder, 1956 from Puenzendorf (SNSB-BSPG 2022 III 39); 10: holotype of Ot. calloviensis Schroeder, 1956 from Puenzendorf (SNSB-BSPG 2022 III 8); 11: holotype of Ot. inaequalis Weiler, 1954 from the Callovian to Oxfordian of Kandern, Baden-Wuertemberg (SMF P. 3067). figs 12 - 13: Leptolepis macrocephalus (Schroeder, 1956); 12: holotype of Ot. guttaeformis Schroeder, 1956 from Puenzendorf (SNSB-BSPG 2022 III 6); 13: holotype of Ot. macrocephalus Schroeder, 1956 from Puenzendorf (SNSB-BSPG 2022 III 1). figs 14 - 16: Leptoelops rhenanus (Weiler, 1954); 14: holotype of Ot. rhenanus Weiler, 1954 from the Callovian of well Bruchsal D 205 (core from 482 to 487 m) near Weingarten, Baden-Wuerttemberg (SMF P. 2953); 15: holotype of Ot. rectisulcatus Schroeder, 1956 from Puenzendorf (SNSB-BSPG 2022 III 37); 16: holotype of Ot. scissus Schroeder, 1956 from Puenzendorf (SNSB-BSPG 2022 III 40).