Haploceras elimatum ( Oppel, 1865 )

Vašíček, Zdeněk & Skupien, Petr, 2025, Revision of haploceratid ammonoids from the Štramberk Limestone, Jurassic-Cretaceous boundary beds (Outer Western Carpathians), Acta Palaeontologica Polonica 70 (3), pp. 421-441 : 424-427

Haploceras elimatum ( Oppel, 1865)

Figs. 3A , 4A , 5, 6F, G.

1865 Ammonites elimatus Opp. ; Oppel 1865: 549.

1868 Ammonites elimatus Opp. ; Zittel 1868: 79, pl. 13: 1a–c (lectotype), 2, 3a, b, 4, 5a–c, 6, 7a, b.

1870 Haploceras elimatum Opp. sp.; Zittel 1870: 51, pl. 27: 7a, b.

1890 Haploceras elimatum Oppel ; Toucas 1890: 576, pl. 13: 4.

1923 Haploceras elimatum (Oppel) ; Spath 1923: 14.

1925 Haploceras elimatum (Oppel) ; Spath 1925: 153, pl. 1: 1a–c.

1953 Haploceras elimatum Oppel ; Arnould-Saget 1953: 8, pl. 1: 9a–c.

?1953 Haploceras elimatum Opp. ; Slavin 1953: 54, pl. 1: 9.

1956 Haploceras elimatum (Opp.) ; Książkiewicz 1956: 211, pl. 25: 6, text-fig. 25.

1960 Haploceras elimatum Opp. ; Collignon 1960: pl. 142: 536, 537.

1960 Haploceras subelimatum Font. ; Collignon 1960: pl. 142: 538.

1960 Haploceras elimatum Oppel ; Drushchits and Kudryavtsev 1960: 267, pl. 13: 1, text-fig. 71.

1962 Haploceras elimatum (Oppel) ; Barthel 1962: 11, pl. 1: 12–15 (= Zittel 1870: pl. 27: 7a, b), text-figs. 15–17.

1965 Haploceras elimatum (Oppel) ; Houša in Špinar 1965: fig. VIII/254.

1966a Haploceras (Haploceras) elimatum ; Wiedmann 1966a: 76, pl. 1: 1a, b.

A B C D E

1966b Haploceras (Haploceras) elimatum (Oppel) ; Wiedmann 1966 b: 61, text-figs. 42b, 43a.

1968 Haploceras (Haploceras) elimatum (Oppel) ; Wiedmann 1968: pl. 1: 3a, b.

1970 Haploceras elimatum (Oppel) ; Patrulius et al. 1970: 138, pl. 2: 11a, b,?fig. 10.

1976 Haploceras (Haploceras) elimatum (Oppel) ; Avram 1976: 34, pl. 8: 1a, b.

1978 Haploceras elimatum (Oppel) ; Olóriz Sáez 1978: 12, pl. 1: 2, 3.

1979 Haploceras elimatum (Oppel) ; Sapunov 1979: 42, pl. 7: 1, 2a, b, text-fig. 4/5 (with synonymy).

1983 Haploceras (Haploceras) elimatum (Oppel) ; Vašíček 1983: 97, pl. 3: 1.

1984 Haploceras elimatum (Oppel) ; Rossi 1984: 88, pl. 31: 11, 12.

1986 ( Haploceras (Haploceras) carachtheis (M) (Zeuschner) morph elimatum ; Enay and Cecca 1986: pl. 4: 3, 4a, b, 5a, b; non pl. 4: 1a, b, 2a, b (= Haploceras staszyci Zejszner ).

1988 Haploceras (Haploceras) elimatum (Oppel) ; Főzy 1988: 51, pl. 2: 1, non pl. 2: 2, 3 (= Haploceras tithonium Oppel ).

?1994 Haploceras elimatum (Oppel) ; Főzy et al. 1994: 158, pl. 1: 10.

?1994 Haploceras elimatum (Oppel) ; Zeiss et al. 1994: 1: 4.

1995 Haploceras elimatum (Oppel) ; Főzy 1995: 136, pl. 20: 9.

1996 Haploceras elimatum (Oppel) ; Wright et al. 1996: 10: 6 /1a, b (= Zittel 1868: pl. 13: 1a, b).

1997 Haploceras (Haploceras) carachtheis Zeuschner morph elimatum (Oppel) ; Benzaggagh and Atrops 1997: pl. 4: 3.

1999 Haploceras cf. elimatum (Oppel) ; Fatmi and Zeiss 1999: 39, pl. 43: 1.

non 1999 Haploceras elimatum (Oppel) ; Kvantaliani 1999: 74, pl. 5: 4 (= Haploceras staszyci Zejszner ).

2000 Haploceras ex gr. elimatum (Oppel) ; Arkadiev et al. 2000: 99, pl. 2: 6a–c.

2001 Haploceras (Haploceras) elimatum (Oppel) ; Zeiss 2001: 37, pl. 5: 6, 7.

2005 Haploceras elimatum (Oppel) ; Boughdiri et al. 2005: 309, pl. 2: 1.

2009 Haploceras elimatum (Oppel) ; Klein et al. 2009: 257 (with synonymy).

2013 Haploceras elimatum (Oppel) ; Főzy and Scherzinger 2013: 214, pl. 4: 5a, b,?pl. 5: 11,? pl. 6: 7.

2013 Haploceras elimatum (Oppel) ; Szives and Fözy 2013: 294, pl. 3: 3.

2016 Haploceras carachtheis morph elimatum (Oppel) ; Hoedemaeker et al. 2016: 169, pl. 17: 7, 8.

2017 Haploceras elimatum (Oppel) ; Főzy 2017: pl. 27: 5, pl. 35: 7.

2020 Haploceras elimatum (Oppel) ; Sarti 2020: 86.

2024 Haploceras elimatum (Oppel) ; Sarti 2024: 86.

Type material: Lectotype SNSB-BSPG AS III 800 was designated by

Spath (1925), originally figured by Zittel (1868: pl. 13: 1 a–c).

Type locality: Štramberk Limestone , Štramberk, Czech Republic .

Type horizon: Tithonian or lower Berriasian .

Material. —In addition to the favourably preserved and published specimens deposited in Munich ( SNSB-BSPG AS III 800–802), more than 30 other non-deformed specimens with sizes ranging from approximately 20 to 200 mm with various degrees of preservation quality were studied. Some specimens deposited in the Moravian-Silesian museums are phragmocones (some with preserved incomplete suture lines), and others are phragmocones with incomplete body chambers. The best preserved specimens are PL2520, PL5056, PL5058, PL5107–5112, B 13569, B 13831, Z1824, Z4224,. However, no completely preserved specimens have been found.

Description. —All specimens are semi-involute, with high, medium-broad whorls and a comparatively narrow umbilicus. The flanks of the whorl are arched. The whorl reaches its greatest breadth relatively close to the umbilical seam. The whorl declines from the area of the greatest arch to the umbilicus more steeply but continuously. No edge is developed on the line of coiling, but there is a narrow, strongly arched zone. Judging from the steinkerns, it is evident that the whorl still plunges inside below the line of coiling so that between the ultimate and penultimate whorls, an empty gap remains in the steinkerns. The flanks of the whorl decline gradually towards the venter. The venter is medium-broad and strongly arched.

The exceptionally well-preserved is medium-sized specimen PL5108 has a recrystallized original shell (Fig. 5D) and in comparison to others, is more conspicuously ribbed. Relatively broad, blunt, and rather widely placed ribs are present mainly on the upper half of the whorl in Haploceras elimatum . The ribs are S-shaped. Near the line of coiling, ribs are faint and concavely bent to the aperture in a short zone. At approximately half the whorl height, the blunt ribs are clearly convexly bent and on the outer side, again concave in a wide shallow arch. Over the venter, the ribs pass without interruption and are slightly inclined towards the peristome. On the original shells, small, fine, dense lines (Fig. 5C 2) are usually preserved near the umbilicus. On the flanks and on the venter, as with the steinkerns, the ribs are usually only slightly pronounced. Very often, ribbing is not preserved at all, and thus, the specimens seem to be or are smooth.

Zittel (1868: pl. 13: 2, 7) illustrated a peristome for two specimens.The smaller specimen, reaching a diameter of approximately 70 mm, has a simpler peristome than the larger specimen. The larger one, with a diameter of approximately 125 mm, displays a peristome with a well expressed lappet.

→ Fig. 5. Haploceratid ammonoid Haploceras elimatum ( Oppel, 1865) from Kotouč Quarry, Tithonian–lower Berriasian, Upper Jurassic–Lower Cretaceous, from author’s own findings in the quarry or from the collection of Lubomir Martinásek (Kopřivnice, Czech Republic). A. PL5058, phragmocone with original test. B. PL5112, specimen with original test and with beginning of body chamber, lateral view. C. PL5110, phragmocone with original test, lateral view (C 1), detail of sculpture around umbilicus (C 2). D. PL5108, specimen with the original test and with a part of body chamber, lateral (D 1) and ventral (D 2) views. E. PL5107, external mould with beginning of body chamber in lateral view (E 1), view on the area near aperture (E 2). F. PL5109, internal mould in lateral view, with the body chamber inclusive of peristome (with rest of original test around umbilicus). The straight line perpendicular to periphery of specimen shows the margin between body chamber and phragmocone.

Almost entire outer suture line is preserved on the juvenile specimen Z4224 (D = 28.5 mm). The external lobe E bears a non-high secondary saddle of rectangular shape. The E/ A saddle is two-branched, with its external branch higher than its internal branch. The mentioned saddle is lower than the A / U saddle. Adventive lobe A is broad and four finger-shaped at the base. On specimen B 13831, an incomplete suture line (E and A) is preserved as well.

Measurements. —The parameters we measured on both juvenile and adult specimens (we measured approximately 30 specimens, see SOM 1, 2, in Supplementary Onine Material available at http://app.pan.pl/SOM/app70-Vasicek_Skupien_ SOM.pdf). The lectotype at D = 61.3 mm (Dmax ca. 70 mm) has H /D = 0.49, U /D = 0.22, B /D = 0. 34. Across the entire size range of the shells, the ratios of the measured parameters remain in similar range: H /D ranges 0.46–0.50, U /D ca. 0.20–0.23, B /D ca. 0.33–0.38. It statistical investigations we initially set an arbitrary boundary between juvenile and adult specimens at a value around the diameter D of ca. 60 mm for practical reasons. In Fig. 7A–C, we have labelled the smaller specimens as “microconchs”, and the larger ones as “macroconchs”. The regression lines are similar in all cases, and the calculated correlation coefficients R are close to 1. Therefore it is implausible to define any statististically meaningful boundary between small and large specimens (see Fig. 7). We conclude therefore that all measured specimens belong to the macroconch category. The terminal size of the adult specimens is around the diameter of 105 mm. These results agree with data of Zeiss (2001).

Remarks. —We could not found any differences neither in the measured parameters nor their morphology and ornamentation between small and large specimens. The peristome in the small specimen illustrated as a drawing by Zittel (1868: pl. 13: 2) does not accurately reflect reality. Its shape, especially the size of the lappet is somewhat reduced. In contrast, in the peristome of the specimen illustrated by Zittel (1868: pl. 13: 7a), a seemingly unrealistic robust lappet is shown. Less conspicuous lappets in large specimens of Ha. elimatum are indicated by growth lines on the flank of the whorls of most specimens, as illustrated in Fig. 5F. This is also valid for the imperfectly preserved peristome of our adult specimen shown in Fig. 5F, which reaches a size similar to that of the specimen in Zittel (1868: pl. 13: 7). Growth lines, which should highlight the conspicuous lappet, are missing also in the lectotype.

Fontannes (1879) established Haploceras subelimatum , which according to its illustration ( Fontannes 1879: pl. 2: 6) differs from Ha. elimatum merely in having narrower whorls. This is also confirmed by the data of B /D values (around 0.27–0.37) in the specimens reported by Sarti (2020). In contrast, Ha. subelimatum as illustrated by Collignon (1960: pl. 142: 538) did not have narrow whorls, and thus, it can be regarded as Ha. elimatum . According to a table showing the measurements of the specimens described by Kvantaliani (1999) as Ha. elimatum , the specimens have broader whorls and narrower umbilicus than both aforementioned species and apparently belong to Ha. staszycii .

Stratigraphic and geographic range.— Haploceras elimatum is known from the whole Mediterranean area from North Africa to the Himalayas and from Madagascar (for more information, see Főzy and Scherzinger 2013). According to figure in Enay and Cecca (1986: fig. 4), which marks the ammonite zonation of the Tithonian, Ha. elimatum has a considerably wide stratigraphic range from the basal Tithonian to the lower Berriasian inclusive (see also Sarti 2020). The lectotype comes from an unspecified part of the Štramberk Limestone in Štramberk. The lower Berriasian occurence is mentioned, e.g., by Arnould-Saget (1953), Olóriz Sáez (1978), Vašíček and Skupien (2013), and Szives and Főzy (2013). Spath (1925) stated that in Madagascar, this species occurs in the Kimmeridgian, but Collignon (1960) corrected it to the lower Tithonian (though also with an imprecise stratigraphy).

Our specimens from the Kotouč Quarry occur, according to the other accompanying ammonites, in both the lower and upper Tithonian (especially locality 4 in Vašíček and Skupien2016), as well as sporadically in the lower Berriasian (Vašíček and Skupien 2013).

Another locality with Ha. elimatum in the Czech Republic is an abandoned quarry near the municipality of Roštín (Rača Nappe of the Magura Unit), namely, in a block con- glomerate with grey marly limestones that, according to the accompanying ammonites, belong to the lower Tithonian ( Vašíček 1983). Other historical occurrences in the Silesian Unit of the Outer Western Carpathians are known from so-called exotic conglomerates, in which the main compo- nent is Štramberk Limestone, in the localities of Koňákov, Chotěbuz, and other ( Hohenegger 1861).

Figures

Fig. 3. Whorl sections of haploceratid ammonoids from Štramberk, Czech Republic, Tithonian–lower Berriasian. A. Haploceras elimatum (Oppel, 1865), SNSB-BSPG AS III 800 (Zittel 1868: pl. 13: 1a) at H = 33 mm. B. Haploceras staszycii(Zejszner,1846),SNSB-BSPGASIII 805 (Zittel 1870: pl. 27: 3a) at H = 37 mm. C. Haploceras tithonium (Oppel, 1865), SNSB- BSPG AS III 798 (Zittel 1868: pl. 14: 2a) at H = 25 mm. D. Hypolissoceras carachtheis (Zejszner, 1846), SNSB-BSPG AS III 47 (Zittel 1868: pl. 15: 1c) at H = 17 mm. E. Hypolissoceras woehleri (Oppel, 1865), MM 06 at H = 27 mm.

Fig. 4. Suture lines of haploceratid ammonoids from Štramberk, Czech Republic, Tithonian–lower Berriasian. A. Haploceras elimatum (Oppel, 1865).Almostcomplete outersuture line ofZ4224at H = 11.5mm.B. Haploceras staszycii (Zejszner, 1846). Substantial part of outer suture line of PL5061 (6th level, middle) at H = 14 mm. C. Haploceras tithonium (Oppel, 1865). Outer and adventive lobes with accompanying saddles of PL5113 at H = 15 mm. D. Hypolissoceras woehleri (Oppel,1865).Adventive lobe with parts of accompanying saddles of MM08 at H = 15 mm.A, adventive lobe; E, external lobe; U2, umbilical lobe.