Eubaculites vagina Forbes 1846 from: Kennedy, W.J..Henderson, R.A.. (1992): Heteromorph ammonites from the Upper Maastrichtian of Pondicherry, south India . Palaeontology Vol. 35 p. 693-731
|Notice: This catalogue page may contain unedited data.
Species Eubaculites vagina Forbes 1846
|Diagnosis / Definition:
Kennedy & Henderson (1992):
The whorls expand quite rapidly, and the shell is slightly curved. The whorl section is compressed, the whorl breadth to height ratio varying between 0.6 and 0.73. The dorsum is broad and flattened, the venter narrow and tabulate, with sharp or narrowly rounded edges. In feebly ornamented variants the whorl section is more compressed, dorsal flanks are divergent, the mid-flank region rounded, and the outer flanks convergent. In strongly nodate variants the whorl section is less compressed, the inner flanks flattened and divergent, with maximum breadth at the mid-lateral tubercle and with flattened to feebly concave ventral flanks in costal section. The venter is distinctly tabulate from as little as 9 mm whorl height, the only smaller specimens seen being poorly preserved, but with a narrowly rounded venter at a whorl height of 8 mm.
A wide range of variation in ornament is attreibuted to the species. At one extreme (Pl. 5, figs. 10-13; Pl. 7, figs. 4-9, 10-12; Pl. 8, figs. 10-12) are variants ornamented by growth lines only. These are sharp on the shell surface (e.g. Pl. 5, fig. 10), but subdued on the mould (Pl. 5, fig. 12). They are broadly convex over dorsum, sweep back across the dorsolateral region, are markedly concave on the dorsal half of the flank, but projected strongly forwards on the ventral half, to intersect the line of the venter at an acute angle. They flex back and are convex over the juncture of flank and venter, passing straight across the venter. Stronger ornament takes the form of broad, ill-defined ribs on the dorsal half of the flanks that strengthens into a feeble mid-lateral node, as in BMNH C2582 and C 73567.
In specimens such as BMNH C77594 (Pl. 7, fig. 13-15), ornament is better differentiated, with a rib index of 2-3.5. The ribs are distant, low and transverse on the dorsal half of the flank, and strengthen into a crescentic mid-lateral tubercle, but decline on the outer flank. As ornament strengthens, a second, dorsolateral tubercle develops, a condition well illustrated by the lectotype (Pl. 7, fig. 16-18), with a rib index of 3. As well as this variation between individuals, ornament changes, generally strengthening, as size increases (Pl. 7, figs. 1-3, 13-18; Pl. 8, figs. 1-9). A notching of the tabulate venter may develop (Pl. 7, fig. 16; Pl. 8, fig. 3), producing an undulose profile to the shell margin but is of variable development within and between individuals. In coarsly ornamented individuals, the dorsolateral tubercle is markedly elongated parallel to the margin of the shell (e.g. BMNH C26300), and the dorsolateral margin undulose in profile (Pl. 9, fig. 13); a broad rib links to the lateral tubercle, which varies from crescentic and oblique (BMNH C7759; Pl. 9, fig. 1-2) to elongated parallel to the length of the shell (BMNH C51141; Pl. 8, fig. 5). The largest specimen seen (BMNH C51140; Pl. 10, figs. 1-3) has a whorl height of 49.5 mm, a whorl breadth to height ratio of 0.6, and a rib index of 5. A marked concavity occupies the ventral part of the flanks, and strengthened growth lines - or riblets - link dorsolateral and mid-lateral tubercles, and extend to the ventrolateral margin. One fragment, BMNH C51146 (Pl. 9, figs. 9-10), shows the aperture, with short dorsal and long ventral rostrum.
Suture (Text-fig. 1C, F) with very broad E with very broad shallow medium saddle; E/L narrower, bifid, L broader than E/L and bifid, L/U, much broader than other saddles, U of intermediate width. All saddles are broad-based, and lobes E, L and U have wide necks.
|Discussion / Comments:
Kennedy & Henderson (1992):
Lectotype, here designated, is BMNH C49726, the original of Forbes (1846, pl. 10, fig. 4), GSC R10488; paralectotypes are BMNH C51140-51150, from the Valudavur Formation of Pondicherry, south India. There are also the following topotypes: BMNH C2582, C77593-77598 (ex Kaye Collection); C2583, C73567-73569, C73590 (ex Marsham Collection); C2597 (ex Forbes Collection); C26299-26300 (ex Spath Collection); C77599-77600.
Wb Wh Wb:Wh Dorsum Venter Rib index
BMNH C51144 7.8 11.8 0.66 4.8(61.5) 1.0(12.8) Smooth
BMNH C51151 11.0 15.7 0.70 6.3(57.3) 2.0(18.2) Smooth
BMNH C51145 — 21.5 — 9.1(—) 4.1(—) 3
BMNH C51149 15.0 23.6 0.64 10.4(69.0) 3.0(12.7) 3
BMNH C77594 16.5 23.7 0.69 11.8(71.5) 4.0(24.2) Smooth
BMNH C51142 16.0 23.8 0.67 11.0(68.8) 4.4(27.5) Smooth
BMNH C51150 16.6 25.9 0.64 10.4(62.6) 3.2(19.2) 2
BMNH C51148 19.3 26.7 0.72 16.3(84.4) 5.1(19.1) 2.5
BMNH C51143 19.3 28.2 0.68 13.2(68.3) 3.2(16.6) 2
BMNH C51147 19.0 29.2 0.65 17.0(89.5) 3.0(15.8) 2
BMNH C26300 21.4 30.0 0.71 17.0(79.4) 3.8(17.8) 2
BMNH C51441 21.1 30.6 0.69 14.9(70.6) 3.6(17.1) 2
BMNH C49762 21.5 32.0 0.67 16.0(74.4) 5.4(16.9) 3
BMNH C51146 — 36.0 — 19.1(—) 9.2(—) —
BMNH C77953 26.5 38.8 0.69 19.0(71.7) 5.5(20.8) 2
BMNH C51140 32.0 50.0 0.64 24.5(76.6) 8.7(27.2) 3
(measurements were taken at the larger end of the specimen; width of dorsum and venter, expressed as a percentage of whorl breadth are shown in parentheses)
The diagnostic features of the type assemblage of E. vagina are the presence of a tabulate venter from an early stage, and binodose ornament on the flanks of a shell that is slightly curved, with a moderately high expansion rate. When compared with other species, these differ as follows; Eubaculites carinatus (Morton, 1834, p. 4, pl. 13, fig. 1; holotype is no 72866 in the collections of the Academy of Natural Sciences, Philadelphia; Text-fig. 5A-C), originally described from the Maastrichtian Prairie Bluff Chalk of Wilcox County, Alabama, has the tabulate venter of the present species, but a flank ornament of concave of concave ribs only, without tubercles. The name carinatus has priority over Baculites tippaensis Conrad, 1858 (p. 334, pl. 35, fig. 27) and B. spillmani Conrad, 1858 (p. 335, pl. 35, fig. 24), originally described from the Owl Creek Formation of Tippah County, Mississippi; and Baculites lyelli d’Orbigny 1847a (pl. 1, figs. 3-7), originally described from Quiriquina Island, Chile among others (see Kennedy 1987, p. 195 for an extensive synonymy). Eubaculites labyrinthicus (Morton, 1834, p. 44, pl. 13, fig. 10, syntypes are nos 72868-72869 in the collection of the Academy of Natural Sciences, Philadelphia; Text-fig. 5D-K) originally described from the Maastrichtian Prairie Bluff Chalk of Alabama, is known in that region as fragments with whorl heights of up to 17.5 mm. The dorsum is flattened, with a dorsolateral node elongated parallel to the length of the shell, linked by a low broad rib to a similarly elongated but obliquely placed mid-lateral tubercle that gives rise to delicate prorsiradiate riblets and striae, which also intercalate. The rib index is 2. This is similar to the ornament of E. vagina, but the venter of E. labyrinthicus is fastigiate rather than broadly tabulate, immediately differentiating the two species.
Eubaculites ootacodensis (Stoliczka, 1866) (= Baculites vagina Forbes var. Ootacodensis Stoliczka, 1866, p. 199, pl. 90, figs. 14, ?15) (lectotypes, designated by Kennedy 1987, p. 195 in the original of Stoliczka, 1866, pl. 90, fig. 14, shown here as Text-fig. 5L-P), originally described from Ootacod, south India, has a binodose lectotype with fastigiate venter, which separates it from E. vagina (see Kennedy 1987, p. 194 for a synonymy). E. simplex (Kossmat, 1895) (=Baculites vagina Forbes var. nov. simplex Kossmat, p. 156 (60), pl. 19 (5), figs. 13a-b, non 14a-b (= E. carinatus)) (lectotype, designated by Kennedy 1987, p. 195, is the original of Kossmat 1896, pl. 19 (5), fig. 13; Text-fig. 6D-F), from Ariyalur, south India, has a completely smooth lectotype, with a narrowly rounded, fastigiate venter, immediatlely separating it from E. vagina. Kennedy 1987, p. 194) thought simplex to be a synonym of E. ootacodensis, but study of large collections from Western Australia show, rather, that it is the senior synonym of Eubaculiceras compressum Brunnschweiler, 1966 (p. 36, pl. 4, figs. 15-17; pl. 5, figs. 1-3; text-fig. 21), E. fastigiatum Brunnschweiler, 1966 (p. 37, pl. 5, figs. 7-9; text-fig. 22), Cardabites tabulatus Brunnschweiler, 1966 (p. 38, pl. 5, figs. 12-15; text-fig. 23), and Cardabites scimitar Brunnschweiler, 1966 (p. 38, pl. 5, figs. 16-21; text-fig. 24). The Australian material has both fastigiate and narrowly tabulate venters, and feeble undulations on the flank of some specimens. The venter of tabulate variants is always much narrower than in smooth variants of E. vagina.
Eubaculites latecarinatus (Brunnschweiler, 1966, p. 33, pl. 3, figs. 13-14; pl. 4, figs. 1-5; text-figs. 17-18), of which Giralites quadrisulcatus Brunnschweiler, 1966 (p. 35, pl. 4, figs. 11-14; text-fig. 20) and Eubaculites ambindensis Collignon, 1971 (p. 18, pl. 646, fig. 2393) are synonyms (see revision in Klinger (1976), and Klinger and Kennedy (in Klinger et al. 1980, p. 296, text-figs. 2-4, 5d)), is characterized by a lack of flank ornament and a broad tabulate venter. Lack of ornament alone distinguishes it from ribbed and tuberculate specimens of E. vagina, and large collections of latecarinatus from Zululand never show significant flank ornament, although the venter may
become notched, so that the species and populations seem distinct enough. More difficult is the distinction between E. latecarinatus and the smooth Eubaculites in the Pondicherry fauna (Pl. 5, figs. 10-13; Pl. 7, figs. 4-9, 10-12; Pl. 8, figs. 10-12; Pl. 9, figs. 9-10; see also Stoliczka 1866, pl. 91, fig. 1 (Text-fig. 6A-C, G-I), and pl. 91, fig. 2 (Text-fig. 6J-L; the latter feebly binodose at the larger end), and the question as to whether or not these smooth individuals should be segregated as E. latecarinatus rather than being referred to E. vagina. Some E. latecarinatus at least have a much more compressed whorl section than the smooth Pondicherry forms, which also lack the pronounced corrugated venter of South African specimens (e.g. Klinger and Kennedy in Klinger et al. 1980, fig. 4) and their dorsal grooves and median ridge (Klinger and Kennedy in Klinger et al. 1980, fig. 30). On balance, given the apparent transition from smooth to ribbed and tuberculate individuals in the Pondicherry assemblages (not seen in South African and Australian E. latecarinatus), we treat them as a single species, admitting however, that some smooth individuals of E. vagina are morphologically inseparable from some E. latecarinatus.
Maastrichtian of Pondicherry, south India, and Madagascar. Zululand representatives (Klinger 1976) may be better referred to E. labyrinthicus (Morton, 1834).
Species Eubaculites vagina
|Kennedy & Henderson (1992):
non 1846 Baculites vagina Forbes. - Darwin
: p.216 [E. carinatus (Morton, 1834)]
p 1866 Baculites vagina Forbes. - Stoliczka
: p.198 pl. 91; fig. 1-6 [non var. ootacodensis, p. 199, pl. 90,
1895 Baculites vagina Forbes. - Kossmat
: 155(59) pl. 19(5); fig. 17 [(a) Typische Form]
non 1897 Baculites vagina Forbes. - Kossmat
: pl. 6; fig. 4 [= E. carinatus (Morton, 1834)]
non 1924 Baculites cf. vagina Forbes. - Crick
: p.130 pl. 9; fig. 1-3 [= E. carinatus (Morton, 1934) and E.
latecarinatus (Brunnschweiler, 1966)]
non 1930 Baculites vagina Forbes. - Wetzel
: p.90 pl. 10; fig. 3-4 [= E. carinatus (Morton, 1834)]
non 1940 Eubaculites vagina Forbes. - Spath
: text-fig. 1a [= E. carinatus (Morton, 1834)]
non 1966 Eubaculites vagina Forbes. - BRUNNSCHWEILER
: p.29 pl. 1, fig. 7;
pl. 2, fig. 1-14;
1976 Eubaculites vagina Forbes. - KLINGER
: p.87 pl. 35, fig. 1-4;
pl. 36, fig. 1-4;
pl. 37, fig. 1-5;
pl. 38, fig. 1-3, ?4;
pl. 39, fig. 2;
pl. 42, fig. 1 [non fig. 4, 7, 9, 11; pl. 43, fig. 5-12]
1989 Eubaculites Spath. - Kennedy : text-fig. 17i-j
1992 Eubaculites vagina Forbes. - Kennedy & Henderson
: p. 715, 721, 723, 72 pl. 5, fig. 10-13;
pl. 7, fig. 1-18;
pl. 8, fig. 1-12;
pl. 9, fig. 1-13;
pl. 10, fig. 1-3;
text-fig. 1C, F
|Stratigraphy - relative ages:
| Maastrichtian: Kennedy & Henderson (1992)
Report on the Cretaceous fossil invertebrates from southern India, collected by Mr. Kaye and Mr. Cunliffe . Transactions of the Geological Society of London Vol. 2(7) p. 97–174
Geological observations on South America. p. I-VIII+279pp.
Paléontologie, Pls. 1-6 (Geologie Pls. 4-9).
In: M. de Dumont D'Urville, 1846-1 854, Voyage au Pole Sud et dans I'Oceanie sur les corvelles L'Astrolabe et la Zelée pendant les années 1837- 1838-1839-1840 sous le commandément de M. Dumont D'Urville Capitaine du Vaisseau. Pls. 1-9 Eds: Baudry, G..
Prodrome de Paléontologie. Stratigraphique universelle des animaux mollusques & rayonnés faisant suitre au cours élémentaire de paléontologie et de géologie stratigraphique. , Cours Élémentaire de Paléontologie et de Géologie Stratigraphiques Vol. 2
The fossil Cephalopoda of the Cretaceous rocks of southern India. Ammonitidae with revision of the Nautilidae etc. . Memoirs of the Geological Survey of India, (l), Palaeontologica Indica10-13 p. 155-216
Untersuchungen über die Südindische Kreideformation. Erster Theil . Beiträge zur Paläontologie Österreich-Ungarns und des Orient Vol. 9 p. 97-203
The Cretaceous deposits of Pondicherri. . Rec. geol. Surv. India Vol. 30 p. 51-110
List of the types andfigured specimens of fossil Cephalopoda in the British Museum (Natural History). p. 103
Die cephalopoden der oberen kreide Südpatagoniens. . Ber. naturf. Ges. Freiburg i. B. Vol. 15 p. 167-248
BOULE,M..; LEMOINE,P.. and THÉVENIN,A.. (1906):
1906-07. Paleontologie de Madagascar IH. Cephalopodes cretaces des environs de Diego-Suarez . Annales de Paleontologie1, 2(1-20, 21-76) p. 173-192, 1-56
Contributions to the palaeontology of Assam . Memoirs of the Geological Survey of India, Palaeontologica IndicaN.S. 8(1) p. 80pp.(4pls.)
Appendix A . Transactions of the Geological Society of South Africa Vol. 26 p. 130-140(pl.9)
Ammonoidea neocretacea . Fossilium Cat, (1: Animalia) Vol. 29 p. 244 pp.
On new ammonites from the English Chalk . Geological Magazine Vol. 3 p. 77-83
Die Quiriquina-Schichten als Sediment und paläontologisches Archiv . Palaeontographica Vol. 73 p. 49-104
Monographie paleontologique du Cretace de la Province de Maintirano. . Mem. geol. Sen. Min. Madagascar p. 86 pp.
Cefalopodi del Cretacea medio-superiore della Zululand . Palaeontographica Italica Vol. 36 p. 59-133(1-75)
On Upper Cretaceous (Maastrichtian) Ammonoidea from Western Australia . Jl. R. Soc. West. Aust. Vol. 26 p. 41-57
Upper Cretaceous ammonites from the Carnarvon Basin of Western Australia 1: the heteromorph Lytoceratina. . Bulletin of the Bureau of Mineral Resources, Geology and Geophysics Vol. 58 p. 5-58
Atlas des fossiles caracteristiques de Madagascar (Ammonites)(Maestrichtian). Vol. 17 p. 82
Cretaceous heteromorph ammonites from Zululand . Memoirs of the Geological Survey of the Republic of South Africa Vol. 69 p. 142 pp
In: Patterns of Evolution Eds: Hallam, A.. p. 251-330
KLINGER,H.C.. and Kennedy,W.J.. (1980):
In: Upper Cretaceous ammonites and inoceramids from the off-shore Alphard Group of south Africa, Annals of the South African Museum Vol. 82 Eds: KLINGER, H.C..Kauffmann, E.G..Kennedy, W.J.. p. 293-320
The ammonite faunas of the type Maastrichtian, with a revision of Ammonites colligatus Binkhorst, 1861 . Bulletin de l'Institut Royal des Sciences Naturelles de Belgique, Sciences de la Terre Vol. 56 p. 151-267
Thoughts on the evolution and extinction of Cretaceous ammonites . Procedings of the Geologists Association Vol. 100 p. 251-279
Kennedy,W.J.. and Henderson,R.A.. (1992):
Heteromorph ammonites from the Upper Maastrichtian of Pondicherry, south India . Palaeontology Vol. 35 p. 693-731
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