Taxon Concept provided by
  Home |   Search

Click on a letter below to get a list of species:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z all
Glyptoxoceras indicum 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
.
Anonymous: Unedited TaxonConcept data
Notice: This catalogue page may contain unedited data.

Species Glyptoxoceras indicum Forbes 1846



Diagnosis / Definition:
Kennedy & Henderson (1992):
DESCRIPTION.- The early whorls (pl. 2, figs. 1, 4-5, 7, 9) are in the form of a very low helix, with a total diameter to the spire of 22 mm, the translation rate being very low. The whorl section is circular at this stage, with coarse , blunt ribs, seperated by somewhat wider interspaces, and a rib index of 6-7. Ribs are weakest on the inner whorl face, feebly rursiradiate, strenghtening and strongly rursiradiate on the upper whorl face, strongest and markedly prorsiradiate on the outer whorl face and weakened and feebly convex on the lower. The lectotype (Pl. 2, figs. 3.12-13) is a 35 mm long, entirely body chamber, consisting of the external mould of a smaller, straight shaft, connected by a stongly curved portion to a longer, straight shaft. The maximum preserved whorl height is 7 mm, the whorl section circular, the rib index 7. Ribs are strong, sharp and narrower than the interspaces. They are feebly prorsiradiate on the flanks of the shaft, and pass straight across the venter, but change to markedly rursiradiate on the hook. BMNH C51111 (Pl. 1, figs. 3-4) is more complete, consisting of the displaced fragments of straight shaft, a curved sector and a second, shorter, straight shaft, the whole forming an asymmetric U. The specimen is partly crushed, but where well preserved, has a maximum whorl height of 12 mm, and a whorl breadth to height ratio of 0.96. The ribbing style is comparable to that of the lectotype; feebly prorsiradiate on the smaller shaft, becoming markedly rursiradiate on the hook and large shaft, but the rib index, 9, is slightly higher on the final shaft. There is a prominent constriction and terminal collar at the aperture, suggesting the specimen to be adult.
Discussion / Comments:
Kennedy & Henderson (1992):
TYPES.- The lectotype, by the subsequent designation of Matsumoto (1959a, p. 167), is BMNH C 51113, the original of Kossmat (1895, pl. 19(5), fig. 4), GSC R10496. Paralectotypes include a part of the lectotype of G. rugatum, BMNH C51100, the original of Forbes (1846, pl. 11, fig. 4a, c); BMNH C51111, the original of Kossmat (1895, pl. 19 (5), fig. 7a-b), GSC R105000, referred by Kossmat to G. rugatum. Possible paralectotypes are BMNH C51130, C51132-51134, C51136, C51138 that belong to the present species; other possible paralectotypes are referred to G. rugatum and G. largesulcatum under these species; all from the Valudavur Formation of Pondicherry, south India. Topotypes are BMNH C4050 (2 fragments), C51117, and C82502-82503 (ex Marsham Collection). DISCUSSION.- Forbes (1846, pl. 11, fig. 4a-c) figured only a fragment of what has been subsequently designated the lectotype of G. rugatum to illustrate the species indicus. Stoliczka (1866, pl. 85, figs. 1-5) used the name, but none of his figured specimen belong to the species as defined here. Kossmat (1895) pointed out that the specimen figured by Forbes as indicum was identical to Forbes's Hamites subcompressus (they were shown by Phillips (1977, p. 124) to be based on bits of the same specimen), and figured a syntype of Forbes's indicus (1895, pl. 19 (5), fig. 4a-b; pl. 2, figs. 3, 12-13) as well as a syntype of Forbes’s rugatus (Kossmat, 1895, pl . 19 (5), fig. 7; Pl. 1, figs. 3-4) which we identify with Glyptoxoceras indicum. Shimizu (1935) considered Forbes’s figured specimen to be the holotype of indicum, but Matsumoto (1959a, p. 167) correctly recognized (following Kossmat, 1895, p. 145(49))that Hamites indicus of Forbes was based upon a number of syntypes, and designated BMNH C51113, the original of Kossmat, 1895 (pl. 19 (5), fig. 4a-b; pl. 1, figs. 3-4) as lectotype. So defined, G. indicum is a distinctive species, characterized by the presence of an initial helix, followed by a single elliptical whorl, beautifully illustrated by examples from the Maastrichtian of California (Matsumoto 1959a, pl. 41, figs. 2-6). The coiling style immediately separates G. indicum from G. rugatum and G. largesulcatum, while G. tenuisulcatum, with similar coiling, has a much higher rib index, the ribs oblique on the venter of shafts rather than transverse, and reaches a much larger size (Pl. 2, figs. 2, 6, 8, 30). The Glyptoxoceras indicum of Brunnschweiler (1966, p. 44, pl. 6, figs. 1-3; text-fig. 28) is G. rugatum. Diplomoceras indicum oestosulcatum Collignon, 1969 (p. 45, pl. 530, fig. 2090), from the Lower Campanian of Madagascar, is based on a straight shaft 80 mm long, a coiling style quite unlike that of G. indicum. The Santonian-Campanian fragments from Zululand and Pondoland (Woods 1906, pl. 44, fig. 2; Klinger 1976, pl. 34, figs. 3, 5) are intermediate. The Diplomoceras (Glyptoxoceras) indicum of Immel et al. (1982, pl. 10, figs. 5-6) from the Santonian of Austria are of uncertain affinities in our view, being densely ribbed curved fragments only. The Glyptoxoceras subcompressum of Ward and Westermann (1976, text-figs. 1-3) and Ward (1976, pl. 1, figs. 1-5; text-fig. 3) consists of an initial helix, followed by one and a half elliptical whorls, rather as in G. indicum, but the plane of coiling of the helix is 90° to that of the late whorls. OCCURRENCE.- Maastrichtian of south India and California.
Synonym list:
Kennedy & Henderson (1992):
p 1846 Hamites indicus Forbes. - Forbes : p.116 [non pl. 11; fig. 4 (=G. rugatum Forbes, 1846)]
non 1847 Hamites indicus Forbes. - d'Orbigny : pl. 3; fig. 13-14 [?=Diplomoceras cylindraceum Defrance, 1816]
1850 Hamites indicus Forbes. - d'Orbigny : p.215
p 1866 Anisoceras sp. indicum Forbes. - Stoliczka : p.181 [non pl. 85; fig. 1-5]
p 1866 Anisoceras tenuisulcatum Forbes. - Stoliczka : p.177 pl. 85; fig. 14 only
p 1895 Hamites (Anisoceras) indicus Forbes. - Kossmat : 145(49) p. 19 (5); fig. 4a-c
p 1895 Hamites (Anisoceras) rugatus Forbes. - Kossmat : p.146 pl. 19 (5); fig. 7 only
non 1906 Hamites (Anisoceras) indicus Forbes. - WOODS : p.340 pl. 44; fig. 2
non 1921 Diplomoceras? sp. indicum Forbes. - Spath : p.256 pl. 23; fig. 5
1935 Glyptoxoceras indicum Forbes. - SHIMIZU : p.272
1954 Glyptoxoceras Spath. - Wright & Matsumoto : text-fig. 5
1959 Glyptoxoceras indicum Forbes. - Matsumoto : p.167 pl. 41, fig. 2-6; text-fig. 80
non 1966 Glyptoxoceras indicum Forbes. - BRUNNSCHWEILER : p.44 pl. 6, fig. 1-3; text-fig. 28 [=G. rugatum]
non 1969 Diplomoceras n spp. indicum octosulcatum Collignon. - COLLIGNON : p.45 pl.530; fig. 2090
non 1976 Diplomoceras (Glyptoxoceras) indicum Forbes. - KLINGER : p.79 pl. 34; fig. 3, 5
1977 Glyptoxoceras indicum Forbes. - Kennedy : text-fig. 31.11-12
non 1982 Diplomoceras (Glyptoxoceras) indicum Forbes. - Immel et al. : p.26 pl. 10; fig. 5-6
1992 Glyptoxoceras indicum Forbes. - Kennedy & Henderson : p. 697, 701 pl. 1, fig. 3-4; pl. 2, fig. 1, 3-5, 7, 9, 12-13
Was used in synonym list of:
Stratigraphy - relative ages:
Maastrichtian: Kennedy & Henderson (1992)
References:

Forbes,E.. (1846):
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

d'Orbigny,A. (1847):
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..

d'Orbigny,A. (1850):
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

Stoliczka,F.. (1866):
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

Kossmat,F.. (1895):
Untersuchungen,über die Südindische Kreideformation. Beitrage zur Palaontologie Osterreich-Ungarns und des Orients . Vol. 9 p. 97-203 (1-107)

WOODS,H.. (1906):
The Cretaceous fauna of Pondoland . Annals of the South African Museum Vol. 4 p. 275-350

Spath,L.F.. (1921):
On Cretaceous Cephalopoda from Zululand . Ann. S. Afr. Mus. Vol. 12 p. 217-321

SHIMIZU,S.. (1935):
The Upper Cretaceous cephalopodes of Japan, part 1. . Journal of the Shanghai Science Institute Vol. 2(2) p. 159-226

Wright,C.. and Matsumoto,T.. (1954):
Some doubtful Cretaceous ammonite genera from Japan and Saghalien.
In: Memoirs of the Faculty of Science, Kyushu University, Series D, Geology, Vol. 4 p. 107-134

Matsumoto,T.. (1959):
Upper Cretaceous ammonites of California, Part II. . Memoirs of the Faculty of Science, Kyushu University, Series D, Geology, Special Volume Vol. 1 p. 1-172

BRUNNSCHWEILER,R.o.. (1966):
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

COLLIGNON,M.. (1969):
Atlas des fossiles caracteristiques de Madagascar (Ammonites). (Campanien inferieur). Vol. 15 p. 216 pp

KLINGER,H.C.. (1976):
Cretaceous heteromorph ammonites from Zululand . Memoirs of the Geological Survey of the Republic of South Africa Vol. 69 p. 142 pp

Kennedy,W.J.. (1977):
Ammonite evolution.
In: Patterns of Evolution Eds: Hallam, A.. p. 251-330

Immel,H..; KLINGER,H.C.. and Wiedmann,J.. (1982):
Die Cephalopoden des Unteren Santon der Gosau von Brandenburg/Tirol, Österreich . Zitteliana Vol. 8 p. 3-32 (11pls)

Kennedy,W.J.. and Henderson,R.A.. (1992):
Heteromorph ammonites from the Upper Maastrichtian of Pondicherry, south India . Palaeontology Vol. 35 p. 693-731

Creative Commons Attribution 2.5 License
This work is licensed under a Creative Commons Attribution 2.5 License.