Amaltheus stokesi ( Sowerby, 1818 )

Amaltheus stokesi ( Sowerby, 1818) View in CoL

( Fig. 3D, E View Fig )

* 1818 Ammonites stokesi Sowerby , p. 205, pl. 190

1822 Ammonites Clevelandicus Young & Bird, pl. 13, fig. 11

1958 Amaltheus stokesi (Sowerby) . Howarth, pl. 1, figs 5–7, 12–14; pl. 2, figs. 1, 3, 10; text-figs. 4, 5 with synonymy

1955 Amaltheus cf. A. nudus (Quenstedt) ; Imlay, p. 87, pl. 10, fig. 5

1958 Amaltheus stokesi (Sowerby) ; Howarth, p. 3, textfig. 4–5, pl. 1, figs. 5, 7, 12–14, pl. 2, figs. 1, 3, 10, with synonymy

1964 Amaltheus stokesi (Sowerby) ; Frebold, pl. 6, figs. 6, 13

1967 Amaltheus stokesi (J. Sowerby) ; Frebold et al., pl. 1, figs. 1, 7

1970 Amaltheus stokesi (J. Sowerby) ; Frebold, pl. 3, fig. 1

1971 Amaltheus sp. cf. A. stokesi (Sowerby) ; Hirano, p. 101, pl. 17, fig. 11

1974 Amaltheus (Amaltheus) stokesi ; Repin, pl. 1, figs. 4–9

1975 Amaltheus stokesi (J. Sowerby) ; Frebold, pl. 4, figs. 3, 4

1976 Amaltheus (Proamaltheus) stokesi (Sowerby) ; Dagis, p. 21, pl. 10, figs. 5–7

1980 Amaltheus stokesi (Sowerby) ; Sey & Kalacheva, pl. 1, figs. 4, 7, 8, 11, 13

1988 Amaltheus stokesi (Sowerby) ; Meister, pl. 1, fig. 1

1988 Amaltheus (Amaltheus) stokesi (Sowerby) ; Krymholts et al., pl. 2, fig. 1

1991 Amaltheus stokesi (J. Sowerby) ; Poulton, p. 18, pl. 8, figs. 2–8 only

1992 Amaltheus stokesi (Sowerby) ; Westermann, pl. 3, fig. 11, pl. 5, fig. 9, pl. 6, fig. 4 (cf.)

1994 Amaltheus cf. A. stokesi (J. Sowerby) ; Pálfy & Hart, pl. 1, fig. 12

1994 Amaltheus stokesi (Sowerby) ; Jakobs & Pálfy, pl. 1, fig. 9

1996 Amaltheus stokesi (J. Sowerby) ; Smith & Tipper, pl. 19, fig. 1, pl. 20, fig. 3

1997 Amaltheus stokesi ; Johannson et al., pl. 2, fig. 13

1998 Amaltheus stokesi (Sowerby) ; Meister, pl. 1, fig. 1

? 2002 Amaltheus margaritatus de Montfort ; Rakús & Guex, pl. 27, fig. 8

2003 Amaltheus stokesi (Sowerby) ; Meister & Friebe, pl. 16, figs. 9, 14; pl. 17, fig. 1 with synonymy

2004 Amaltheus stokesi (Sowerby) ; Schubert, pl. 1, fig. 6

2005 Amaltheus stokesi (Sowerby) ; Callomon & Gradinaru, pl. 2, fig. 2

2006 Amaltheus stokesi (J. Sowerby, 1818) View in CoL ; Topchishvili et al., pl. 11, figs. 4, 5

2006 Amaltheus stokesi (Sowerby) View in CoL ; Fauré, p. 41 fig. 7.8; p. 43, fig. 8.5

2007 Amaltheus stokesi (Sowerby) ; Rulleau et al., pl. 34, fig. 1; pl. 35, fig. 1a-b

2007 Amaltheus stokesi (Sowerby) ; Mouterde et al., pl. 1, figs. 9, 14

2008 Amaltheus cf. stokesi (Sowerby) ; Seyed-Emami et al., p. 245, fig. 4B

2010 Amaltheus stokesi (Sowerby) ; Comas-Rengifo & Goy, pl. 1, fig. 4

2011 Amaltheus stokesi (Sowerby) ; Shirmohammad et al., pl. 1, fig. 14

2011 Amaltheus stokesi (Sowerby) ; Nakada, p. 99, pl.4, figs. 1–5

2012 Amaltheus ( Amaltheus) stokesi (Sowerby) ; Hoedemaeker, p. 78, pl. 17 L

2016 Amaltheus ( Amaltheus) stokesi (Sowerby) ; Repin, pl. 4, figs. 4, 5

2016 Amaltheus stokesi (Sowerby) ; Nützel et al., p. 231, fig. 2

2021 Amaltheus stokesi (Sowerby) ; Nakada et al., p. 1009, fig. 4

2020–2021 Amaltheus stokesi (Sowerby) ; Fauré, pl. 4, figs. 8–10

2022 Amaltheus ex. gr. stokesi (Sowerby) ; Hostettler et al., pl. 4, fig. 3

2023 Amaltheus stokesi (Sowerby) ; Bohain et al., pl. 11, figs. 5, 6a–b, 7a–b, pl. 12, fig. 1a–c

2023 Amaltheus stokesi (Sowerby) ; Meyer, pl. 3, figs. H-I.

2025 accepted A. (Amaltheus) stokesi (Sowerby) ; Meister et al., pl. 79, fig. 11, pl. 80, fig. 1

Material: A single fragment (Ge 33501).

Description: Tis moderately involute species includes large oxycone morphologies with a highly compressed elliptical whorl section. Te venter bears a barely developed, rounded keel, broad and elevated, with coarse crenulation. Each serration of crenulated keel is connected with a rib. Te ribs are radial and are stronger on the inner two-thirds of the flank, becoming weaker on the upper part of the flank, where they are strongly projected forward in the ventrolateral part and join the keel without further weakening. Te specimen from Lukoveček fits well with these characters, showing straight and strong ribs in the lower-middle parts of flank, weakening upward and turning forward in the latero-ventral area, where they are bifurcating and each secondary rib pass to an individual crenulation of the keel.

Remarks: Te connecting pattern between the ribs and crenulations and other characteristics of the keel are the main features which distinguish Amaltheus stokesi from Amaltheus margaritatus de Montfort, 1808 . Te keel in Amaltheus margaritatus is more individualised with finer crenulation. Also, the ribbing seems a little bit weaker in this species.

Occurrence: Amaltheus stokesi is the index species of the Stokesi Subzone at the base of the Upper Pliensbachian of the standard zonation (Meister, 1988). It has been recognised in the Northwest European Province, the northern Tethys margin (Southern Alps, Austroalpine units, Carpathians), the Caucasus ( Georgia), East Asia ( Japan), North American Cordillera ( British Columbia and northern Alaska), Arctic Canada, and Russia (the Northeast, the Siberian Platform and the Far East). Te here described specimen is the first record of the species from the Outer Western Carpathians ( Czech Republic).