Calliphylloceras disputabile ( Zittel, 1868 )

Galácz, András, 2017, Bajocian (Middle Jurassic) ammonites of stratigraphical and palaeobiogeographical importance from Mombasa, Kenya, East Africa, Geodiversitas 39 (4), pp. 717-727 : 721-722

Calliphylloceras disputabile ( Zittel, 1868) ( Fig. 5 G-H)

Phylloceras disputabile Zittel, 1868: 606 .

Ammonites tatricus – Kudernatsch 1852: 4, pl. 1, figs 1-4.

non Phylloceras cf. disputabile – Spath 1920: 318, pl. 5, fig. 4a-d.

? Calliphylloceras cf. disputabile – Spath 1930: 22.

Calliphylloceras cf. C. disputabile – Westermann 1975: 38, pl. 1, fig. 6.

Calliphylloceras disputabile – Galácz 1990: 202.

REMARKS

The specimens are easy to recognise by the wide-oval crosssection of the swollen whorls, especially at small sizes. The other characteristic feature is the straight, slightly projected constrictions. The form determined by Spath as close to C. disputabile ( Spath 1920: pl. 5, fig. 4) most probably belongs to Ptychophylloceras longarae (see Westermann 1975: 37, and below). Genus Calliphylloceras Spath, 1927 is common in East Africa, in Madagascar ( Joly 1976) and in Kachchh ( Spath 1927), in the latter two regions with the same species.

Holcophylloceras zignodianum (d’Orbigny, 1848) ( Fig. 5 I-J)

Ammonites zignodianus d’Orbigny, 1842: 493, pl. 182, figs 1-2. Holcophylloceras mediterraneum – Spath 1930: 23.

Holcophylloceras zignodianum – Galácz 1980: 41, pl. 5, figs 4-5; pl. 6, fig. 1; pl. 7, fig. 1; text-figs 30-32 (cum syn.); 1990: 202.

REMARKS

H. zignodianum has characteristic inner whorls and nuclei with proportionally wide umbilicus and very strong, unmistakable constrictions. The Mombasa specimens are nuclei or fragments of middle whorls, those phragmocone parts where the otherwise characteristic high-lateral and ventral ribs are not developed ont he available specimens.

Holcophylloceras Spath, 1927 , similarly as Calliphylloceras , is widely distributed in the later Middle Jurassic through the Upper Jurassic of East Africa and of the wider Indo- Malgashi area.

Ptychophylloceras lardyi (Ooster, 1860) ( Fig. 5 E-F)

Ammonites lardyi Oooster, 1860: 71 , pl. 19, figs 7-9.

Ptychophylloceras (P.) lardyi – Pavia 1983: 16, pl. 3, fig. 4, pl. 4, figs 10, 11, 13, 14, text-figs 4, 6, 9 (cum syn.)

Ptychophylloceras lardyi – Parnes 1988: 713, pl. 1, figs 8-11.

Ptychophylloceras haloricum – Galácz 1990: 202.

REMARKS

These nuclei were determined previously as Ptychophylloceras haloricum (see Galácz 1990: 202). Better specimens from the new collection show the suture-line which is consistent with those figured by Pavia (1983: text-fig. 4). The specimens represent the innermost whorls which show only the funnelshaped periumbilical area but just under the size where the first characteristic ventral constrictions and ridges appear. Pavia (1983: 16) restricted the stratigraphic distribution of the species to the Garantiana Zone.

Lytoceras eudesianum eudesianum (d’Orbigny, 1846) ( Figs 3 ; 6A, B )

Ammonites eudesianus d’Orbigny, 1846: 386, pl. 128, figs 1-3.

Lytoceras adeloides – Douvillé 1916: 13, pl. 2, fig. 1. — Parnes 1988: 713, pl. 1, fig. 29.

Lytoceras eudesianum eudesianum – Galácz 1980: 48, pl. 9 (cum syn.)

Lytoceras eudesianum – Galácz 1990: 202.

REMARKS

The impression of a large specimen ( Fig. 3 ) and the small pyritic moulds ( Fig. 6A, B ) displaying clearly the thin crinkled collars which appear periodically among the straight riblets. The geographically closest record is the ‘ L. adeloides’ from the Sinai ( Douvillé 1916: 13, pl. 2, fig. 1; Parnes 1988: 713, pl. 1, fig. 29). Both figured forms are too old (i.e., Late Bajocian) to be L. adeloides ( Kudernatsch, 1852) , and are most probably L. eudesianum .

Nannolytoceras polyhelictum ( Böckh, 1881) ( Figs 4F ; 5K, L )

Lytoceras polyhelictum Böckh, 1881: 35 , pl. 1, figs 2, 3.

Protetragonites cf. tripartitus – Spath 1920: 355, pl. 5, fig. 6a-c.

Nannolytoceras aff. N. polyhelictum – Westermann 1975: 36, pl.1, fig. 7.

Nannolytoceras polyhelictum – Galácz 1990: 202. — Galácz & Kassai 2012: 291, figs 7a-d, 8e, 9g-h.

REMARKS

Several specimens of this characteristic Upper Bajocian Nannolytoceras . They differ from other, much rarer species with their high-oval whorl-section and constrictions: there are four on these inner whorls and they are narrow and prorsiradiate on the flanks. Spath, and later Westermann also described and figured the species (see synonymy above). A lectotype was designated and figured recently from the original material of Böckh (see Galácz & Kassai 2012).

Lissoceras oolithicum (d’Orbigny, 1845) ( Fig. 5 O-P)

Ammonites oolithicus d’Orbigny, 1845: 383, pl. 126, figs 1-4.

Lissoceras oolithicum – Douvillé 1916: 17, pl. 3, fig. 9. — Galácz 1980: 57, pl. 11, figs 5,6, text-figs 43, 44 (cum syn.); 1990: 202.

Lissoceras sp. cf. L. (L.) oolithicum – Parnes 1988: 721, pl. 2, figs 13-17.

REMARKS

A small fragment of a wholly septate internal cast. Characteristic is the oval whorl-section with convex flanks and highly-arched venter. The suture-line is very poorly preserved, but the details of the typical haploceratid suture are discernible.

This is a Bajocian Ammonitina species with extremely wide north-south geographic range. This Mombasa locality is almost on the equator, and the northernmost record is from Isle of Skye, Scotland ( Morton 1971: 40, figs 1,2). It is also recorded from the Sinai ( Douvillé 1916: 17, pl. 3, fig. 9 and Parnes 1988: 721, pl. 2, figs 13-17).

Figures

FIG. 5. — A, B, Phylloceras trifoliatum Neumayr, 1871 MR 1, EMNH.2015.286; C, D, Phylloceras trifoliatum Neumayr, 1871 MR 2, EMNH.2015.285; E, F, Ptychophylloceras lardyi (Ooster,1860) MR 1, EMNH.2015.303; G, H, Calliphylloceras disputabile (Zittel,1868) MR 1, EMNH.2015.304; I, J, Holcophylloceras zignodianum (d’Orbigny, 1848) MR 1, EMNH.2015.259; K, L, Nannolytoceras polyhelictum (BÖckh,1881) MR 2, EMNH.2015.257;M, N, Trimarginia sp. MR 2, EMNH.2015.279; O, P, Lissoceras oolithicum (d’Orbigny,1845) MR 2, EMNH.2015.268;Q, R, Oecotraustes sp. MR 1, EMNH.2015.249;S,?Diplesioceras sp.MR 1, EMNH.2015.180; T, U, Cadomites (Cadomites) sp. MR 1, EMNH.2015.232; V, W, Normannites egyptiacus Arkell, 1952 MR 2, EMNH.2015.288; X, Y, Spiroceras annulatum (Deshayes, 1831) MR 2, EMNH.2015.287. Scale bar: 10 mm.

FIG. 3. — Occasional preservation of big ammonite specimens (Lytoceras eudesianum eudesianum (d’Orbigny, 1846)),as shown here with an imprint in the Upper Shaley member of the Kambe Formation (locality MR 1). Scale bar:10 mm.

FIG. 6. — A, B, Lytoceras eudesianum eudesianum (d’Orbigny, 1846) MR 1, EMNH.2015.184; C, Masckeites cf. psilacanthoides (Sandoval, 1983) MR 2, EMNH.2015.278; D, Leptosphinctes cf. schmiereri (Bentz, 1924) MR 2, EMNH.2015.224. Scale bar: 10 mm.

FIG. 4. — Suture lines of some important species: A, Oecotraustes sp. MR 1, EMNH.2015.249; B, Cadomites (Cadomites) sp. MR 1, EMNH.2015.232; C,?Diplesioceras sp. MR 1, EMNH.2015.180; D, Spiroceras annulatum (Deshayes, 1831) MR 2, EMNH.2015.287; E, Leptosphinctes cf. schmiereri (Bentz, 1924) MR 2, EMNH.2015.224; F, Nannolytoceras polyhelictum (BÖckh, 1881) MR 2, EMNH.2015.257; G, Trimarginia sp. MR 2, EMNH.2015.279. Scale bar: 5 mm.