Leptolepis normandica Nybelin, 1962

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

Leptolepis normandica Nybelin, 1962

Plate 1, figs 1-15

Otolithus ornatus 1956 Otolithus cf. ornatus Weiler, 1953 - Schröder: pl. 6, figs 1-3.

Otolithus opalini 1956 Otolithus opalini - Schröder: pl. 6, fig. 9 (non figs 7-8).

Otolithus cristatus 1956 Otolithus cristatus - Schröder: pl. 6, figs 13-14.

Otolithus vastus 1956 Otolithus vastus - Schröder: pl. 7, figs 36-38.

Otolithus brevis 1956 Otolithus ( Lycopteridarum ?) brevis - Weiler: pl. 3, figs 16-19.

Otolithus brevirostris 1965 Otolithus ( Lycoperidarum ?) brevirostris - Weiler: pl. 3, figs 20-23.

Otolithus elegans ?1965 Otolithus ( Lycopteridarum ?) elegans - Weiler: pl. 3, figs 24, 25, pl. 4, fig. 26.

Otolithus similis 1965 Otolithus ( Lycopteridarum ?) similis - Weiler: pl. 2, figs 10-13, pl. 3, figs 14-15.

Leptolepis normandica 1997 Leptolepis normandica Nybelin, 1962 - Delsate: figs 1-5, pl. 1, fig. 4, pl. 2, figs 5-9 (otoliths in situ).

Leptolepis normandica 2013 Leptolepis normandica Nybelin, 1962 - Nolf: pl. 6.

Otolithus similis 2014 Otolithus ( Lycopteroidarum ?) similis Weiler, 1965 - Hesse: fig. 18A-G.

Otolithus brevis 2014 Otolithus ( Lycopteroidarum ?) brevis Weiler, 1965 - Hesse: fig. 19A-F.

Otolithus ornatus 2014 Otolithus ( Lycopteroidarum ?) Lycopteroidarum ornatus Weiler, 1953 - Hesse: fig. 20A-D.

Otolithus 2014 Otolithus (inc. sed.) sp. 1 - Hesse: fig. 21A-C.

Otolithus ?2014 Otolithus (inc. sed.) sp. 2 - Hesse: fig. 22A-B.

Otolithus 2014 Otolithus (inc.sed.) sp. 3 - Hesse: fig. 23A.

Otolithus 2014 Otolithus (inc. sed.) sp. 5 - Hesse: fig. 25A.

Leptolepis ?2014 Leptolepis sp. - Hesse: fig. 32 (otolith in situ).

Leptolepis normandica 2018 Leptolepis normandica Nybelin, 1962 - Schwarzhans: fig. 1C-H.

Leptolepis normandica 2021b Leptolepis normandica Nybelin, 1962 - Keupp: fig. 9.3 B.

Material.

264 specimens: 251 specimens from the late Pliensbachian of Buttenheim : 8 specimens Apyrenum subzone (figured specimen SNSB-BSPG 2022 IV 1, Plate 1 , fig. 10) , 1 specimen “Quellhorizon” (figured specimen SNSB-BSPG 2022 IV 2, Plate 1 , fig. 9) , 242 specimens Hawkerense subzone (figured specimen SNSB-BSPG 2022 IV 3, Plate 1 , figs 1-8, 11) ; 13 specimens from Schröder’s collection from the late Toarcian to early Aalenian: paratype of Ot. cristatus from Kremmeldorf (SNSB-BSPG 2022 III 5, Plate 1 , fig. 12) , 4 specimens designated as Ot. cf. ornatus with 3 from Kremmeldorf and 1 from Peulendorf (SNSB-BSPG 2022 III 11-13) , 3 paratypes of Ot. opalini from Kremmeldorf (SNSB-BSPG 2022 III 20-22, Plate 1 , fig. 13), holotype of Ot. vastus from Peulendorf (SNSB-BSPG 2022 III 30, Plate 1 , fig. 15) , 4 paratypes of Ot. vastus from Kremmelsdorf (SNSB-BSPG 2022 III 31 -34, Plate 1 , fig. 14) .

Differential diagnosis.

Otoliths of Leptolepis normandica are more compressed than other coeval species of Leptolepis with an OL:OH ratio of 1.25-1.45 (vs.>.1.5), but less compressed than that of L. steberae sp. nov. (1.1-1.25). The rostrum is shorter than that of L. buttenheimensis sp. nov. ranging from about 30 to 36% of OL (vs. 37-45%), but longer that those of L. steberae sp. nov. (12-25%). The short postdorsal rim is higher than that of L. curvisulcatus and L. kremmeldorfensis and longer than that of L. kremmeldorfensis . The ostium tends to be wider in L. normandica than in coeval Leptolepis species except of L. steberae sp. nov. (OsH:CaH = 1.5-2.2 vs 1.25-1.6).

Discussion.

Leptolepis normandica is the most common otolith-based species so far recognized in the Early Jurassic and the early Middle Jurassic (Pliensbachian to Aalenian). Its distinction from coeval species is not always easy to determine, particularly regarding L. curvisulcatus , and transitional forms exist. The type specimens of the synonymized species of Weiler ( 1965) and Schröder (1956) are mostly small and sometimes not very well-preserved; nevertheless, they bear the pertinent diagnostic characteristics. The specimens of this species exhibit a considerable variability, which may have led Weiler and Schröder to establish many species that can no longer be maintained after review. The variability encompasses primarily the shape of the postdorsal rim, width of the cauda and to a lesser degree its curvature, and ornamentation of the rims. Due to the large degree of variability, we have figured many specimens from Buttenheim in comparison to selected refigured specimens of Schröder. The largest specimen from Buttenheim is 2.85 mm in length; the largest specimen from Schröder’s collection is 2.4 mm. Otoliths attributable to L. normandica have been found in Pliensbachian to Aalenian strata in Belgium ( Nolf 2013), Luxemburg ( Delsate 1997), England, and Germany.

Figures

Plate 1. Otoliths of Leptolepis normandica and L. curvisulcatus. figs 1 - 15: Leptolepis normandica Nybelin, 1962; 1 - 11: From late Pliensbachian of Buttenheim, 1 - 8, 11: EPH horizon (SNSB-BSPG 2022 IV 3); 9: " Quellhorizon " (SNSB-BSPG 2022 IV 2); 10: Apyrenum subzone (SNSB-BSPG 2022 IV 1); 12: paratype of Ot. cristatus Schroeder, 1956 from Kremmeldorf (SNSB-BSPG 2022 III 5); 13: paratype of Ot. opalini Schroeder, 1956 from Kremmeldorf (SNSB-BSPG 2022 III 20); 14: paratype of Ot. vastus Schroeder, 1956 from Kremmelsdorf (SNSB-BSPG 2022 III 34); 15: holotype of Ot. vastus from Peulendorf (SNSB-BSPG 2022 III 30). figs 15 - 19 Leptolepis curvisulcatus (Schroeder, 1956); 15: paratype of Ot. opalini Schroeder, 1956 from Kremmeldorf (SNSB-BSPG 2022 III 17); 16: holotype of Ot. curvisulcatus Schroeder, 1956 from Kremmeldorf (SNSB-BSPG 2022 III 42); 17: holotype of Ot. schattenbergi Schroeder, 1956 from Kremmelsdorf (SNSB-BSPG 2022 III 2); 18: paratype of Ot. schattenbergi Schroeder, 1956 from Kremmelsdorf (SNSB-BSPG 2022 III 47); 19: holotype of Ot. opalini Schroeder, 1956 from Kremmeldorf (SNSB-BSPG 2022 III 16).