*1841 Ammonites tortisulcatus. – Orbigny, p. 162, pl. 51, figs. 4–6.

1849 Ammonites tortisulcatus. – Quenstedt, p. 506, pl. 189, figs. 1–3.

1887 Ammonites tortisulcatus. – Quenstedt, p. 898, pl. 97, figs. 1–5.

1994 Sowerbyceras protortisulcatum (Pompeckj). – Schlegel-Milch, p. 21, pl. 1, fig. 2.

Lectotype: Original of Orbigny 1849, pl. 189, figs. 1–3, stored in the Institut de Paléontologie du Muséum Paris, R. 505 and 3534F (Orbigny Collection), subsequently designated by Atrops (in Fischer 1994: 166).

Material: One specimen, semiarmatum Biohorizon (Plettenberg section, bed 10).

This small-sized ammonite is ornamented with four to six deep sinuous constrictions per whorl crossing the venter. The suture lines show phylloid saddles typical of phylloceratids as well as a characteristic delicate midline in its ventral symmetry plane. Whorl section trapezoidal; umbilicus moderately wide.

Sowerbyceras tortisulcatum is generally rare in the Oxfordian of Swabia and indicates a Tethyan influx. Although we have not recorded Sowerbyceras tortisulcatum from the semimammatum Biohorizon of the Plettenberg section, it cannot be excluded that it occurs in that biohorizon as well.

*1831 Ammonites alternans. – Buch, pl. 7, fig. 4.

1849 Ammonites alternans ovalis. – Quenstedt, p. 96, pl. 5, fig. 8.

1857 Ammonites alternans. – Quenstedt, p. 617, pl. 76, fig. 14.

1887 Ammonites alternans oblongus. – Quenstedt, p. 824, pl. 91, figs. 1, 2.

1887 Ammonites alternans. – Quenstedt, p. 824, pl. 91, figs. 4, 6, 13.

1907 Cardioceras alternans (Buch). – Oppenheimer, p. 239.

1915 Cardioceras ovale (Quenstedt). – Salfeld, p. 167, pl. 16, figs. 1, 2, 8, 9.

1915 Cardioceras alternans (Buch). – Salfeld, pl. 16, fig. 6.

1930 Cardioceras ovale (Quenstedt). – Dorn, p. 80, pl. 24, figs. 25–27.

1930 Cardioceras alternans (Buch). – Dorn, p. 81, pl. 25, figs. 3–5.

1963 Cardioceras (Amoeboceras) alternans (Buch). – Koerner, p. 344.

1963 Cardioceras (Amoeboceras) ovale (Quenstedt). – Koerner, p. 344.

1977 Amoeboceras alternans. – Ziegler, p. 20, pl. 9, fig 1.

1981 Amoeboceras alternans. – Klieber, p. 281, fig. 9.

1987 Amoeboceras alternans. – Ziegler, p. 9, pl. 9, fig. 1.

1994 Amoeboceras (Amoeboceras) alternans (Buch). – Schlegel-Milch, p. 29, pl. 7, fig. 2.

1994 Amoeboceras (Amoeboceras) ovale (Quenstedt). – Schlegel-Milch, p. 30, pl. 7, fig. 3.

2000 Amoeboceras (Amoeboceras) ovale (Quenstedt). – Matyja & Wierzbowski, fig. 5.1.–5.7.

2000 Amoeboceras alternans (Buch). – Schweigert, p. 204, pl. 1, fig. 4.

2000 Amoeboceras ovale (Quenstedt). – Schweigert, p. 204, pl. 1, fig. 5.

2003 Amoeboceras alternans (Buch). – Schairer & Schlampp, p. 18, pl. 1, figs. 1, 2.

Type material and remarks: Neotype of Amoeboceras alternans: GPIT CP 18600; holotype of Amoeboceras ovale: GPIT CP 17609.

The holotype of Ammonites alternans comes from the locality “Lochen” near Balingen. This specimen, which was part of the Schlotheim collection in Berlin, became apparently lost soon after its description. Quenstedt (1849) illustrated a specimen from the same locality with a narrower umbilicus and a denser ribbing as Ammonites alternans ovalis, but later he clearly stated (Quenstedt 1857: 617) that he had not intended to establish a new subspecies and pointed to the great intraspecific variation (Quenstedt 1887: 824). Later, however, Salfeld (1915) separated the material of Quenstedt into the two taxa alternans and ovale, in which he was subsequently followed by numerous authors. The sole specimen illustrated by Quenstedt (1849, pl. 5, fig. 8) is regarded as the holotype of Amoeboceras ovale; whereas the specimen illustrated by Quenstedt (1887, pl. 91, fig. 6) was subsequently suggested as the neotype of Amoeboceras alternans (Sykes & Callomon 1979: 864). This neotype substantially differs from the holotype in showing a wider umbilicus, a wider-spaced ribbing and the presence of faint spines at the bifurcations of the ribs. Koerner (1963) mentioned the occurrence of transitional morphologies linking A. alternans and A. ovale. Later, Klieber (1981) observed a sample of 72 specimens from Franconia with statistical methods. He was unable to find any bimodal distribution between the two morphospecies A. alternans and A. ovale, which is why he favoured their synonymisation. We have studied another sample of 63 specimens from the semimammatum Biohorizon (Figs. 7, 8). Our material confirms a broad intraspecific variation. The conch morphology of the holotype of Amoeboceras ovale lies within the centre of variation, as well as the holotype of A. alternans, if the illustration was correct. The position of the neotype of Amoeboceras alternans lies still within the variation, but closer to the margin. Comparison of the number of ribs leads to the same conclusion, except for the number of secondaries in the Amoeboceras alternans holotype (see Appendix). However, this number might be erroneous, since the lateral and ventral views of Buch's (1831) illustration do not match in this point. Consequently, we follow Klieber (1981) and consider Amoeboceras ovale (Quenstedt, 1849) as a subjective junior synonym of Amoeboceras alternans (Buch, 1831). A. alternans is not restricted to the semimammatum Biohorizon, but is already present in the underlying Bifurcatus Zone (Schweigert 2000).

Material studied: 212 specimens, all from the semimammatum Biohorizon.

Amoeboceras alternans (Buch, 1831) is a small, highly variable ammonite. The biggest specimens rarely reach more than 40 mm in diameter. The most common morph has a discoidal conch shape. It is weakly compressed, with nearly parallel flanks, a high whorl expansion rate and a moderate to narrow umbilical width. The retroradiate to rectiradiate ribbing is prominent, with frequent bifurcations above mid-flank and some intercalations. Some extreme morphologies show spine-like thickenings at the point of bifurcation. All ribs end median with a protruding thickening. The venter exhibits a densely serrate keel. As this keel is prominent, the knobs do not reach the conch body, which is the case in younger chronospecies of Amoeboceras, except A. praebauhini (Salfeld, 1913). The ribs never touch the keel, which is a significant difference to the older genus Cardioceras. The body chamber comprises about 2/3 of the last whorl. The aperture is not preserved in our studied material. Amoeboceras alternans is most abundant in the close surroundings of siliceous sponge-microbial bioherms, which probably provided both shelter and prey.

1930 Cardioceras cf. nathorsti Lundgren. – Frebold, p. 75, pl. 26, figs. 2, 3 (LT).

1935 Amoeboceras (Prionodoceras) regulare. – Spath, p. 25.

1967 Amoeboceras (Prionodoceras) regulare Spath. – Mesezh-Nikov, p. 117, pl. 1, fig. 2.

1979 Amoeboceras regulare Spath. – Sykes & Callomon, p. 881, pl. 118, figs. 9 [LT], 10.

Amoeboceras regulare Spath, 1935 is supposed to be the macroconchiate partner of Amoeboceras alternans (Buch, 1831), since it exhibits a very similar shape and ornamentation, except of a significantly larger size. Macroconchs are extremely rare in the Late Oxfordian of the Submediterranean Province. A sole fragment is reported here; it has been found on the lowest floor of the Plettenberg Quarry, most likely coming from beds containing the semimammatum Biohorizon.

*1863Ammonites lochensis. – Oppel, p. 207, pl. 54, fig. 1.

1887 Ammonites lochensis. – Quenstedt, p. 859, pl. 93, figs. 28, 29.

1887 Ammonites pichleri. – Quenstedt, p. 858, pl. 93, figs. 17, 18.

1930 Neumayriceras lochense (Oppel). – DORN, p. 50, pl. 13 (29), figs. 4, 9, 10.

1955 Taramelliceras lochense (Oppel). – Hölder, p. 124, supplement 18, fig. 162.8.

1973 Taramelliceras (Richeiceras) lochense (Oppel). – Ziegler, p. 30.

1994 Taramelliceras(Proscaphites)lochense(Oppel).–Schlegel-Milch, p. 33, pl. 7, fig. 17.

2003 Taramelliceras (?) lochense (Oppel). – Schairer & Schlampp, p. 19, pl. 1, fig. 4.

Type: Oppel (1863) mentioned 20 syntypes from the Lochen and Streitberg sites, of which the illustrated specimen from Lochen (Oppel 1863, pl. 54, fig. 1) was erroneously considered as the holotype by Schlegelmilch (1994). We here designate that specimen (SNSB-BSPG AS VIII 175) as the lectotype.

Material: 263 specimens (two from bed 2; 19 from bed 3; nine from bed 5; seven from bed 7; one from bed 8; 191 from bed 10; four from bed 11; three from bed 13; 2 from bed 18, and 25 from Wassergraben)

Oppel (1863) introduced two rather similar oppeliid species coming from his Bimammatum Subzone, Ammonites lochensis and Ammonites pichleri (see Pl. 1, Fig. 14), which have been frequently recorded in this interval (now divided into the Hypselum and Bimammatum zones). It seems that Richeiceras pichleri is just a little bit more strongly sculptured than R. lochense and otherwise identical. However, since the holotype of R. pichleri comes from Streitberg in Bavaria, with no precise indication about its exact type horizon, the usage of the taxon R. lochense instead of R. pichleri is preferred here.

Richeiceras lochense (Oppel) rarely exceeds 35 mm in diameter. Its involute conch is discoidal and strongly depressed. While this general shape is rather constant, the sculpture is widely variable. Beginning with an almost smooth nucleus, the ornamentation sets on with a row of fine and densely spaced knobs on the venter and weak falcoid ribbing. The ribs are dense, with abundant bifurcations and thickenings at mid-flank. On the body chamber, such thickenings are absent and occasionally the projecting ribs are weakly crossing the venter. Above mid-flank many intercalatory ribs occur. The body chamber length comprises slightly more than half a whorl.

A small quantity of specimens exhibits ornamentations similar to Richeiceras tricristatum (Oppel), a larger-sized species of the bimammatum Biohorizon which may represent a phyletic descendant of R. lochense. Together with its microchonchiate partner Coryceras canale (Quenstedt), R. lochense is one of the predominant taxa of the two described biohorizons, especially of the semiarmatum Biohorizon. Like in Amoeboceras alternans (Buch), mass occurrences of R. lochense are always situated close to sponge-microbial bioherms.

*1930Neumayriceras externnodosum. – Dorn, p. 49, pl. 13 (29), fig. 8, 11, 12.

1955 Taramelliceras (Strebliticeras) externnodosum (Dorn). – Hölder, p. 91, supplement 3, figs. 51–55.

1991 Taramelliceras externnodosum. – Schlampp, p. 82, pl. 29, fig 4 and cover.

1994 Streblites externnodosus (Dorn). – Schlegelmilch, p. 43, pl. 12, fig. 11.

2003 Taramelliceras(?)externnodosum.–Schairer&Schlampp, p. 19, pl. 1, figs. 7, 10, 11.

2009 Taramelliceras externnodosum Dorn. – Bonnot et al., pl. 6, fig. 23.

Lectotype: Original of Dorn 1930, pl. 13 (29), fig. 8; not traceable and apparently lost.

Material: 67 specimens (one from bed 1; 11 from bed 3; two from bed 7; one from bed 8; 45 from bed 10; one from bed 11; one from bed 13; one from bed 18; four from Wassergraben).

Taramelliceras externnodosum (Dorn) shows about the same conch shape as R. lochense (Oppel), with a tendency towards a bigger whorl width. The adult size considerably exceeds that of R. lochense (Oppel), with the largest specimen from the Plettenberg section having a diameter of 55 mm and the largest one recorded from Gräfenberg (Franconia) even reaching a diameter of 139 mm (pers. comm. V. Schlampp). The sculpture of T. externnodosum (Dorn) is more prominent than that of R. lochense (Oppel) and rib swellings at mid-flank are well developed. Stronger ornamented specimens of T. externnodosum (Dorn) somewhat recall T. costatum (Quenstedt, 1849) from the younger bimammatum Biohorizon of the basal Kimmeridgian (Fig. 9b). In T. costatum (Quenstedt) looped ribs connecting the rib swellings at the bifurcation points with the terminal nodes along the ventrolateral margin are common. T. costatum (Quenstedt), however, has a higher whorl section, and in T. externnodosum (Dorn) looped ribs are totally absent. Another difference is obvious in the ventral denticles, which are densely spaced in T. externnodosum (Dorn) (see Fig. 9).

Some authors (Schlegelmilch 1994; Schweigert & Callomon 1997) have assigned T. externnodosum (Dorn) to Streblites, but is has neither a continuously serrated floored keel nor an oxyconic conch shape characteristic for that genus. Hölder (1955: 90) mentioned the presence of conellae-filled hollow nodes on the venter as an argument in favour of such a placement. Since there is a huge stratigraphical gap until the sudden appearance of the type species Streblites tenuilobatus (Oppel) in the Early Kimmeridgian Hypselocyclum Zone and the ancestry of this genus is still unknown, the species externnodosum is here preliminarily kept in Taramelliceras.

Although being much less abundant than R. lochense (Oppel), T. externnodosum (Dorn) is a typical element of the semimammatum and semiarmatum biohorizons.

*1848Ammonites lingulatus canalis. – Quenstedt, p. 130, pl. 9, fig. 17.

1857 Ammonites lingulatus canalis. – Quenstedt, p. 619, pl. 76, fig. 13.

1887 Ammonites lingulatus laevis. – Quenstedt, p. 849, pl. 92, fig. 40.

1887 Ammonites lingulatus canalis. – Quenstedt, p. 849, pl. 92, figs. 41, 42, 43, 45.

1887 Ammonites lophotus. – Quenstedt, p. 858, pl. 93, figs. 21, 23.

1887 Ammonites microdomus. – Quenstedt, p. 859, pl. 93, figs. 25, 26.

1958 Glochiceras (Coryceras) canale (Quenstedt). – ZIEGLER, p. 123, pl. 11, figs. 15–18.

1991 Glochiceras (Coryceras) canale (Quenstedt). – Gygi, p. 18, pl. 5, fig. 1.

1994 Glochiceras (Coryceras) canale (Quenstedt). – Schlegelmilch, p. 53, pl. 16, fig. 3.

Holotype: Original of Quenstedt 1848, pl. 9, fig. 17 (= Quenstedt 1887, pl. 92, fig. 41), stored in the Palaeontological Collection of Tübingen University (GPIT CP 17618).

Material: 109 specimens (two from bed 3; one from bed 5; 14 from bed 7; 73 from bed 10; two from bed 11; 17 from Wassergraben).

A very small-sized ammonite with adult specimens rarely reaching diameters of 20 mm. In the last part of the phragmocon and in the beginning of the adult body chamber fine denticles frequently occur on the venter, but in some specimens these may be absent. Towards the aperture the venter becomes smooth. Apart from these ventral denticles there is no further ornamentation. On the flanks no significant lateral depression is developed. Dorsolaterally, the aperture meets the inner whorl in a straight to slightly inclined position. Ventrally, the mouth border is inclined as well. The long lappets end in an elongated plate. This plate, however, is rarely preserved.

Coryceras canale (Quenstedt) is the most common small ammonite of the semimammatum and semiarmatum biohorizons. It is regarded here as the microconchiate partner of Richeiceras lochense (Oppel), since both taxa have the same stratigraphical ranges and fit well in their size relations and ventral aspects.

1863Ammonites microdomus. – Oppel, p. 204, pl. 53, fig. 5.

1887 Ammonites lingulatus canalis. – Quenstedt, p. 850, pl. 92, figs. 46, 47.

1887 Ammonites microdomus. – Quenstedt, pp. 851, 859, pl. 92, fig. 50; pl. 93, fig. 27.

1958 Glochiceras (Coryceras) microdomum (Oppel). – Ziegler, p. 122, pl. 11, figs. 12–14.

1991 Glochiceras (Coryceras) microdomus (Oppel). – Gygi, p. 17, pl. 3, figs. 2–5.

1994 Glochiceras (Coryceras) microdomus (Oppel). – Schlegel-Milch, p. 33, pl. 16, fig. 2.

2009 Glochiceras microdomum (Oppel). – Bonnot et al., pl. 6, figs. 4, 6–12.

Holotype: Original of Oppel 1863, pl. 53, fig. 5; SNSB-BSPG AS VIII 6/5.

Material: 38 specimens (one from bed 1; one from bed 2; eight from bed 3; one from bed 5; two from bed 7; 18 from bed 10; seven from Wassergraben).

Coryceras microdomus (Oppel) is somewhat similar to the above described C. canale (Quenstedt), but notably bigger. In optimal preservation, a fine, prorsiradiate ribbing is developed on the body chamber which has been nicely illustrated by Oppel (1863). Ventral denticles are less common than in C. canale (Quenstedt).

Coryceras microdomus is abundant both in the semimammatum and semiarmatum biohorizons. It is regarded as the microconch partner of Taramelliceras externnodosum (Dorn) due to the co-occurrence and similarities in early growth stages of both taxa.

*1857 Ammonites trimarginatus. – Oppel, p. 687.

1863 Ammonites trimarginatus. – Oppel, p. 159, pl. 50, fig. 2.

1887 Ammonites complanatus. – Quenstedt, p. 833, pl. 91, figs. 33, 34.

1961 Trimarginites arolicus (Oppel). – Christ, p. 283, pl. 16, figs. 2, 3.

1991 Trimarginites trimarginatus (Oppel). – Schlampp, p. 92, pl. 34, fig. 2.

1994 Trimarginites trimarginatus (Oppel). – Schlegelmilch, p. 47, pl.14, fig. 6.

2009 Trimarginites trimarginatus (Oppel). – Bonnot et al., pl. 6, fig. 26, 27.

Lectotype: Although this species is based on three syntypes (Oppel 1863), Christ (1961) regarded the single illustrated specimen (Oppel 1863, pl. 50, fig. 2; SNSB-BSPG AS VIII 39) as the type specimen. This is accepted here as a subsequent lectotype designation. The lectotype comes from the Impressamergel Formation of Hundsrücken near Balingen-Streichen, probably from the bauhini Biohorizon.

Material: Three specimens (one from beds 3–7, one from bed 17, one from bed 18).

This taxon is extremely discoidal in cross section, with a narrow umbilicus. Except from the three-keeled venter, there is no further ornamentation. T. trimarginatus (Oppel) has been found only once ex situ at the foot of the studied section, but the finding locality and the rock matrix indicate an origin from the beds 3–7. Two further records, a juvenile and a fragmentary one, come from higher strata. From the well-studied profile in the Deuerlein Quarry in Gräfenberg (Franconia), T. trimarginatus (Oppel) is known as a very rare element of the semimammatum Biohorizon (Victor Schlampp, pers. comm.). Hitherto, it has not been found in beds of the semiarmatum Biohorizon, and its microconchiate partner Trimarginites aff. stenorhynchus (Oppel, 1863) is yet unrecorded in both biohorizons.

*1947Ochetoceras basseae. – Fradin, pl. 13, figs. 1, 2.

2009 Ochetoceras basseae Fradin. – Bonnot et al., pl. 5, fig. 10.

Holotype: Original of Fradin 1947, pl. 13, figs. 1, 2.

Material: 40 specimens (three from bed 3; 20 from bed 5; four from bed 7; five from bed 10; eight from Wassergraben).

Species with narrow umbilical width and a flat, oxycone conch, showing a keel with fine denticles. The floored keel is only preserved under favorable conditions. The prominent ornamentation is two-faced: at mid-flank a deep spiral groove is developed. Dorsolaterally from the groove, the strong ribs are prorsiradiate, while above the groove a denser ribbing starts retroradiate with a tendancy to swing foreward at the median end. Below and above the groove the ribs may develop a slight thickening. Bifurcations are rare and only present above the groove. The ornamentation starts at a diameter of about 15 mm. The largest recorded specimen, still wholly septate, measures 63 mm. Ochetoceras basseae Fradin is present in the semiarmatum Biohorizon, but less abundant than in the semimammatum Biohorizon (especially in the middle part). Höroldt (1964: 65) interpreted O. basseae as a subjective junior synonym of O. his-pidiforme (Fontannes, 1879); however, the bulk of our studied specimens represent a morphology typical of O. basseae. Bonnot et al. (2009: 380) reported both taxa from exactly the same layer and hence supposed that these taxa represent different morphologies of a single species. Since our material does not allow a statistical analysis, which could support a unification of both taxa, we prefer keeping both separate.

A remarkable number of specimens have broad whorl sections and are strongly sculptured, thus closely resembling O. hispidum (Oppel, 1863). Oppel had reported this species from the Transversarium Zone, but the holotype comes from the vicinity of Balingen, where strata of the Transversarium Zone were only rarely exposed. Quenstedt's specimens (1887, pl. 92, figs. 9–11) assigned to O. hispidum (Oppel, 1863) come from the “Lochen” site and most likely from one of the herein described biohorizons.

*1958Glochiceras (Glochiceras) tectum. – Ziegler, p. 109, pl. 10, fig. 6.

1994 Glochiceras (Glochiceras) tectum Ziegler. – Schlegelmilch, p. 51, pl. 15, fig. 15.

2009 Glochiceras tectum Zeiss [sic]. – Bonnot et al., pl. 5, figs. 7, 13.

2014 Glochiceras (Glochiceras) tectum Ziegler. – Jantschke, p. 220, pl. 2, fig. 4.

Holotype: Original of Ziegler 1958, pl. 10, fig. 6; SMNS 19346.

Material: Eight specimens (two from bed 3, one from bed 7; three from bed 10; two from Wassergraben).

Glochiceras tectum is an almost smooth-shelled, small- to very small-sized species with a narrow umbilicus. The flattened conch exhibits a fastigate venter, sometimes with a keel-like appearance. On the body chamber, a shallow lateral depression is developed. At the aperture, there is a ventral hook. Long, spoon-like lappets are developed. Dorsolaterally, the aperture is drawn backwards. The body chamber comprises about three quarters of the last whorl. This taxon occurs both in the semimammatum Biohorizon and in the semiarmatum Biohorizon, but it is never common.

*1887Ammonites semimammatus. – Quenstedt, p. 885, pl. 95, fig. 20.

1907 Peltoceras bimammatum. – Oppenheimer, p. 241, pl. 21, figs. 5–7.

1907 Peltoceras uhligi. – Oppenheimer, p. 241, pl. 21, figs. 10–12.

1930 Peltoceras uhligi. – Dorn, p. 71, pl. 18 (34), figs. 10–23.

1930 Peltoceras retrocostatum. – Dorn, p. 72, pl. 18 (34), fig. 7.

1930 Peltoceras circumcostatum. – Dorn, p. 73, pl. 17 (33), figs. 13,14.

1937 Peltoceras stromeri. – Prieser, p. 64, fig. 12c.

1962 Epipeltoceras semimammatum semimammatum (Quenstedt). – Énay, p. 61, pl. 4, figs. 6,7, 8, 12.

1962 Epipeltoceras semimammatum uhligi (Oppenheimer). – Énay, p. 66, p. 4, figs. 9, 10.

1962 Epipeltoceras semimammatum stromeri Prieser. – Énay, p. 66, pl. 4, figs. 13, 15.

1994 Epipeltoceras semimammatum (Quenstedt). – Schlegelmilch, p. 67, Taf. 23, Fig. 7.

2003 Epipeltoceras semimammatum (Quenstedt). – Schairer & Schlampp, p. 20, pl. 2, fig. 4.

2009 Epipeltoceras semimammatum (Quenstedt). – Bonnot et al., pl. 8, figs. 1–8; pl. 9, figs. 11–15.

Holotype: Original of Quenstedt 1887, pl. 95, fig. 20; SMNS 14486.

Material: 19 specimens (four from bed 3; seven from bed 5; four from bed 7; four from Wassergraben).

Quenstedt (1887: 885) originally interpreted E. semimammatum as a variety of E. semiarmatum and since he had only little material, he “did not want to flaunt with new names”. However, as this name was published, later on, several authors regarded this as a new species. Oppenheimer (1907) introduced E. uhligi as a new species based on material from Brno (nowadays Czech Republic), but his specimens are well within the variation of E. semimammatum (see Énay 1962). The same is true for E. circumcostatum (Dorn, 1931), E. retrocostatum (Dorn, 1931) and E. stromeri (Prieser, 1937), which are therefore considered here as junior subjective synonyms.

The small index species of the semimammatum Biohorizon is not abundant. Its conch shape and rib density are quite constant. The umbilical width is moderate to wide; the whorl expansion rate is low. The whorl section is rounded. The ribs are mostly simple and widely spaced. Bifurcations are rare, and, if present, located close to the umbilical edge. Starting rectiradiate, the ribs tend to become retroradiate, especially on the body chamber. While the ribs cross the venter in the juvenile state, they later end at the ventrolateral margin in a weak nodule, leaving the venter smooth. Only in few extreme variants ribs may cross the venter also in the adult stage. The height of the venter mostly exceeds the height of the nodules. The latest one to three ribs often do not start at the umbilical edge but at mid-flank. The body chamber comprises one half of a whorl. The aperture bears long, tongue-like lappets.

*1887Ammonites semiarmatus. – Quenstedt, p. 885, pl. 95, fig. 19.

1962 Epipeltoceras semiarmatum (Quenstedt). –ÉNAY, p. 59, pl. 4, figs. 1, 11, 16.

1994 Epipeltoceras semiarmatum (Quenstedt). – SCHLEGELMILCH, p. 67, pl. 23, fig. 6.

2009 Epipeltoceras semiarmatum (Quenstedt). – BONNOT et al., pl. 8, figs. 9–15; pl. 9, figs. 16–20.

Holotype: Original of Quenstedt 1887, pl. 95, fig. 19, stored in the Palaeontological Collection of Tübingen University (GPIT CP 18692).

Material: 56 specimens (all from bed 10).

When Quenstedt (1887: 885) established this species based on material from the Lochen site, he already noticed some relationship to what is now identified as Clambites hypselus (Oppel).

This species is similar to the older E. semimammatum, but some differences are obvious. The main difference is the adult size. In E. semimammatum, the maximum diameter is 21–25 mm, where in E. semiarmatum it ranges from 27 to 36 mm. The ribbing shows a tendency to project backwards as well, but it is more constant, with hardly any bifurcations and exhibits a smooth venter, especially on the body chamber. The height of the more prominent rib nodules is equal or a little bit higher than the venter itself.

*1863 Ammonites hypselus. – Oppel, p. 229, pl. 64, fig. 2.

1887 Ammonites perarmatus. – Quenstedt, p. 888, pl. 96, fig. 1.

1994 Clambites hypselum (Oppel). – Schlegelmilch, p. 120, pl. 63, fig. 1.

2000 Euaspidoceras hypselum (Oppel). – Gygi, pl. 10, fig. 1.

2009 Euaspidoceras hypselum (Oppel). – Bonnot, pl. 7, figs. 3, 5, 11.

Holotype: Original of Oppel 1863, pl. 64, fig. 2; SNSB-BSPG AS VIII 61.

Material: 16 specimens from the semimammatum Biohorizon (three from bed 3; three from bed 5; four from bed 7; four from Wassergraben); 53 specimen from the semiarmatum Biohorizon (all from bed 10).

The holotype of this species is a phragmocone; a maximum diameter of about 170 mm can be estimated for the complete specimen. The conch is subevolute to evolute in shape with a wide whorl and minor overlap. The simple ornamentation consists of widely spaced rectiradiate ribs with a prominent knob on both the umbilical and median ending. The knobs are therefore paired from a juvenile state of about 20 mm onwards. All of these knobs carry hollow spines, which are normally not preserved. At very small diameters widespaced prorsiradiate ribs are crossing the venter. At a diameter of about 10 mm the outer knobs begin. In these early states occasionally looped ribs and fine, dense intercalations occur. The venter is smooth and rounded. The body chamber comprises about one half of the last whorl.

Clambites hypselus (Oppel) has been regarded in the past as the corresponding macroconch to Epipeltoceras semimammatum (Quenstedt), which would demand a different species as counterpart for the younger taxon Epipeltoceras semiarmatum (Quenstedt). But as the variation is great and the number of adult specimens is still low, no differences can be pointed out between specimens from the semimammatum Biohorizon and others from the semiarmatum Biohorizon. The latter specimens are termed here as Clambites aff. hypselus. Possibly, this taxon corresponds to Clambites eucyphus (Oppel, 1863), which, according to the illustration, exhibits a slightly narrower whorl section and is more weakly sculptured than our material. Dorn (1930) had splitted his material from Franconia into 30 individual species. He almost ignored any possibility of intraspecific variation. Even taken into account that his material was not collected from a single bed and locality, only his “Aspidoceras” lenki, some late Euaspidoceras spp. and a form leading to Epaspidoceras mamillanum (Quenstedt) seem to be specifically different from C. hypselus.

*1887Ammonites microbiplex. – Quenstedt, p. 876, pl. 94, fig. 36.

1898 Perisphinctes microbiplex. – Siemiradzki, p. 192.

1907 Perisphinctes divergens. – Oppenheimer, p. 253, pl. 22 (3), fig. 13.

1907 Perisphinctes procedens. – Oppenheimer, p. 254, pl. 22 (3), fig. 3.

1907 Perisphinctes guebhardi. – Oppenheimer, p. 254, pl. 22 (3), fig. 10.

1930 Perisphinctes microbiplex. – Dorn, p. 160, pl. 27 (13), fig. 5.

1930 Perisphinctes monteiroi. – Dorn, p. 161, pl. 27 (13), fig. 4.

1936 Microbiplices microbiplex. –Arkell, p. xli.

1973 Microbiplices microbiplex. – Ziegler, p. 31.

1994 Microbiplices microbiplex (Quenstedt). – Schlegelmilch, p. 62, pl. 21, fig. 3.

2003 Microbiplices microbiplex (Quenstedt). – Schairer & Schlampp, p. 20, pl. 2, figs. 7, 8.

2003 Prorasenia sp. 1. – Schairer & Schlampp, p. 24, pl. 2, figs. 11.

2003 Prorasenia sp. 2. – Schairer & Schlampp, p. 24, pl. 2, figs. 12.

2003 Prorasenia sp. 3. – Schairer & Schlampp, p. 24, pl. 2, figs. 12.

Holotype: Original of Quenstedt 1887, pl. 94, fig. 36; stored in the Palaeontological Collection of Tübingen University (GPIT CP 18679). Arkell (1936) based his newly introduced genus Microbiplices on this specimen, but it seems unnecessary to split the microconchiate genus Prorasenia further, especially for material from the Submediterranean Province.

Material: 16 specimens from the semimammatum Biohorizon (five from bed 3; one from bed 5; six from bed 7; four from Wassergraben).

A species with a wide umbilicus and rounded whorls, reaching more than 40 mm in adult size. Microconch of Ringsteadia salfeldi (Dorn) (cf. Sykes & Callomon 1979). The ribbing is strong and slightly prorsiradiate, with bifurcation points not far from the median edge. At juvenile stages rare trifurcations occur at this point; also intercalations crossing the venter start from here. One to two shallow constrictions per whorl are present, especially at younger stages. The ribbing starts densely and gets continuously wider. The bi- and trifurcation points are not visible in the inner whorls. Note that the ribbing is wider and more prominent compared to the younger P. bathyschista Koerner, 1963. The body chamber takes about ¾ of the last whorl. The aperture shows a long, tongue-like apophysis. Remarkably, Prorasenia microbiplex (Quenstedt) and its supposed macroconchiate partner Ringsteadia salfeldi (Dorn) are virtually absent in beds of the semiarmatum Biohorizon.

1925 Ringsteadia salfeldi. – Dorn, p. 531, pl. 22, figs. 1–3.

1994 Ringsteadia flexuoides (Quenstedt). – Schlegelmilch, p. 99.

2003 Ringsteadia salfeldi (Dorn). – Schairer & Schlampp, p. 28, pl. 3, fig. 6.

Types: Originals of Dorn 1925, pl. 22, figs. 1–3.

Material: Five specimens from the semimammatum Biohorizon (two from bed 3; one from bed 5; one from bed 7; one from Wassergraben).

This discoidal ammonite has a narrow to moderately wide umbilicus and an oval whorl section. The ribbing is slightly prorsiradiate, with bifurcations occurring above mid-flank. Together with many intercalating ribs starting at the hight of the bifurcation points, they cross the rounded venter unchanged. In the juvenile stage, two or three shallow constrictions per whorl are developed. The adult size is expected to reach diameters of more than 100 mm; however, such adult specimens have not yet been recorded. One typical specimen was found ex situ at the foot of the studied section, but its rock matrix indicates an origin from the interval of beds 3–7. Ringsteadia salfeldi has been only recorded from the semimammatum Biohorizon. A small specimen from bed 17 shows a much denser ribbing and a narrower umbilicus as usual; in this respect, it is closer to Ringsteadia flexuoides (Quenstedt, 1888) from the bimammatum Biohorizon (see Jantschke 2014).

1893 Ammonites fontannesi. – Choffat, p. 40, pl. 9, fig. 1.

pars 1994 Orthosphinctes (Orthosphinctes) polygyratus (Quenstedt). – Schlegelmilch, p. 64.

2009 Orthosphinctes fontannesi (Choffat). – Bonnot et al., pl. 1, fig. 2.

Holotype: Original of Choffat 1893, pl. 9, fig. 1.

Material: 61 specimens from the semimammatum Biohorizon (16 from bed 3; eight from bed 5; 23 from bed 7; 14 from Wassergraben); 40 specimens from the semiarmatum Biohorizon (all from bed 10).

This species is characterized by a wide umbilicus, rounded whorls and a large whorl width. The dense, slightly prorsiradiate ribbing becomes more widely spaced with size. Ribs are mostly bipartite, with a relatively high but inconstant bifurcation point. Simple and polygyrate ribs are present as well. In the latter there is a tendency to form a thickening at the lower bifurcation point. In addition, median parabolic nodes and looped ribs occur. One or two constrictions per whorl, sometimes only weakly developed, occur. Complete lappeted specimens are expected to reach diameters of about 90 mm, but they have not yet been found. Orthosphinctes is regarded as the microconchiate partner of Pseudorthosphinctes (Schweigert & Callomon 1997).

aff. 1966 Decipia girardoti. – Énay, p. 559 ff., pl. 39, figs. 1, 3; pl. 40, fig. 2.

2009 Lithacosphinctes cf. girardoti Énay. – Bonnot et al., pl. 3, fig. 1; ? pl. 4, fig. 1.

Holotype: Original of Énay 1966, pl. 39, fig. 1 from Chaumont (Dpt. Jura, France), stored in the collection of University Lyon-Villeurbanne, no. 75.586.

Material: Four specimens (two from bed 3, Plettenberg).

Pseudorthosphinctes aff. girardoti is the biggest-sized ammonite species of the two described biohorizons, with diameters of more than 300 mm in adult specimens. Its coiling is evolute; the whorl section is rounded, becoming oval in the later stages. The ribbing starts slightly prorsiradiate and later becomes rectiradiate. Due to unfavourable preservational conditions, only four specimens of this species have been recorded. The largest one was found ex situ and broken into numerous parts. The body chamber is almost smooth, but this might result from poor preservation. Another specimen was recovered just below a thin layer containing numerous Amoeboceras alternans (BUCH, 1831) which clearly indicates bed 7.

2003 Subdiscosphinctes (Subdiscosphinctes) sp. – SCHAIRER & SCHLAMPP, p. 40, pl. 4, fig. 2.

Material: Seven specimens (one from bed 8; six from bed 10).

This rare species recalls the stratigraphically older Subdiscosphinctes lucingae (Favre, 1875) from the Transversarium Zone. Compared with the more abundant Orthosphinctes fontannesi (Choffat, 1893), the umbilicus is narrower in Subdiscosphinctes, while the whorl height is larger. The sharp ribs are more densely spaced and generally prorsiradiate. Constrictions are rare; polygyrate ribs have not been observed.

1966 ?Praeidoceras n. sp. – Énay, p. 572, pl. 40, fig. 7.

cf. 1989 Passendorferia (Enayites) arancensis. – Meléndez, pl. 12, fig. 18.

2003 Graefenbergites arancensis (Meléndez). – Schairer & Schlampp, pl. 7, figs. 1, 3, 4.

2008 Graefenbergites arancensis [m]. – Schlampp, fig. 3.

2009 Passendorferia (Enayites) arancensis Meléndez. – Bonnot et al., pl . 2, fig. 6.

2018 Graefenbergites cf. arancensis (Meléndez). – Maisch & Matzke, fig. 1.

Holotype: Original of Énay 1966, pl. 40, fig. 7, from Aranc (Dépt. Ain, France), stored in the collection of University Lyon-Villeurbanne, no. 75.811.

Material: Six specimens (two from bed 5; three from bed 10; one from Wassergraben).

Evolute coiling with rounded to oval whorl section. Dense bipartite convexe ribbing; bifurcation point near mid-flank. One or two deep constrictions per whorl and many intercalatory ribs occur. A single macroconchiate specimen from the Impressamergel Formation of the Plettenberg, most likely coming from beds of the semimammatum Biohorizon, has been described by Maisch & Matzke (2018) in great detail. Graefenbergites is a rare but typical Tethyan element of both biohorizons.

1989 Barthelticeras enayi. – Schairer, p. 121, pl. 3, figs. 1, 2.

Holotype: Original of Schairer 1989, pl. 3, fig. 1; SNSB-BSPG 1986 XII 51.

Material: Four specimens (one from bed 5; two from beds 3–7; one fragment from bed 10).

An unusual ammonite with a very wide umbilicus and a rectangular whorl section. The weak ribbing consists of very fine simple ribs, which may occasionally bifurcate. On the inner whorls the ribs are slightly prorsiradiate; they change their inclination to slightly rectiradiate on the body chamber. Towards the body chamber, the venter tends to become smooth. Parabolic nodes occur. On the body chamber three to four deep prominent constrictions are developed.