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
Hypophylloceras (Neophylloceras) surya Forbes 1846 from: Ifrim, C..Stinnesbeck, W..López-Oliva, J.G.. (2004): Maastrichtian cephalopods from Cerralvo, north-eastern Mexico . Palaeontology Vol. 47(6) p. 1575–1627
.
Anonymous: Unedited TaxonConcept data
Notice: This catalogue page may contain unedited data.

Species Hypophylloceras (Neophylloceras) surya Forbes 1846

[1]
[2]
[1] Text-fig. 2c-e Ifrim et al. (2004) [2] Text-fig. 3a Ifrim et al. (2004)

Alternative name:
Diagnosis / Definition:
Ifrim et al. (2004):
Description: Shell discoidal and involute with intermediate expansion rate. Compression of the whorl section increases with diameter. The wide umbilicus (0·20-0·25) is surrounded by steep umbilical walls that pass into the flanks in a wide arch. The flanks are slightly convex with the maximum whorl breadth above the middle flank. Flanks converge ventrally and pass into the broadly rounded venter in a wide bow. The dorsal flanks present six bullae per half whorl. Six to eight parallel, slightly prorsiradiate and concave lirae are present between two bullae, but they are not visible in the dorsal area. On the middle flank lirae are straight but become convex towards the venter where they cross rectiradially. Suturallobes are deep and fine incisions with phylloid saddle terminations and a shallow ventral lobe. The suturallobe is retracted.
Discussion / Comments:
Ifrim et al. (2004):
Remarks: The most conspicuous features of the specimens described here are the wide umbilicus and the dorsolateral bullae. Species of Hypophylloceras (Neophylloceras) with a similarly wide umbilicus are H. (N) surya (Forbes, 1846), H. (N) marshalli (Shimizu, 1935), and H. (N) cottreaui (Collignon, 1956). In Text-figure 4 the whorl diameter is plotted against the umbilical diameter to evaluate a possible relationship of the Cerralvo specimens with one of the above species. Hypophylloceras (Neophylloceras) surya (Forbes, 1846) shows eight or more bullae per half whorl in more adult stages as compared to six per whorl reported here for the Cerralvo specimens (e.g. Henderson and McNamara 1985; Kennedy and Henderson 1992b). The specimens described here may be juveniles of this species as suggested by the UID relationship (Text-fig. 4). However, in that case an increase in the number of umbilical bullae should exist during ontogeny, a change that has not been described so far. Hypophylloceras (Neophylloceras) cottreaui (Collignon, 1956) was described from a single specimen which is much larger than our juveniles. lt differs from other Neophylloceras in having a very wide umbilicus (UID = 0·17). In addition, it is more inflated and characterized by six strong bullae per half whorl arranged close to the umbilicus. The bullae were described by Collignon (1956, p. 25) as 'flat costae with quadratic cross section that are separated from each other by a deep groove.' This feature cannot be evaluated properly in the specimens described here. In addition, umbilical tubercles are described by Collignon (1956) which are absent in the present specimens. Hypophylloceras (Neophylloceras) marshalli (Shimizu, 1935; Henderson 1970) is another species with a wide umbilicus and ornament of 'fine, closely spaced ribs which are slightly prorsiradiate on the dorsal flanks, straighten at the mid-flank and are rectiradiate across the venter; the dorsal flanks bear six folds in a half whorl' (Henderson 1970, p.3). The U/D relationship reported coincides with our material (Textfig. 4), but the sigmoidal bending of the dorsolateral ribs and their density differ from our specimens. On the other hand the specimen described by Henderson (1970) is larger (D is 42·0mm). Another species with similar ornament is H. (N) infiatum (Stinnesbeck, 1986), but this species differs considerably from the Cerralvo specimens in test size ratios and in having a whorl section that is much more inflated (Text-fig. 4). In addition, the ontogenesis of H. (N) infiatum clearly follows a different path in the U/D relationship. Shell measurements (Text-fig. 4) suggest that the Cerralvo specimens may be juveniles of H. (N) surya, although they are too small to allow precise determination. Occurrence: Hypophylloceras (Neophylloceras) surya (Forbes) has been recorded from the Maastrichtian of southern India (Kennedy and Henderson 1992b), Madagascar (Collignon 1956), South Africa (Kennedy and Klinger 1976), western Australia (Henderson and McNamara 1985), the Biscay region, Alaska, California, Japan (Ward and Kennedy 1993) and Denmark (Birkelund 1993), and the Upper Maastrichtian of Pakistan (Fatmi and Kennedy 1999) and Chile (Stinnesbeck 1986).
Synonym list:
Ifrim et al. (2004):
1846 Ammonites surya Forbes. - Forbes : p.106 pl. 7, fig. 10
1850 Ammonites surya Forbes. - d'Orbigny : p.213
1895 Phylloceras surya Forbes. - Kossmat : 109 (13) pl. 16 (2), fig. 1
1956 Epiphylloceras mikobokense Collignon. - COLLIGNON : p.24 pl. 2, figs. 3,3a; pl. 4, figs. 5,5a,5b
1965 Phylloceras (Neophylloceras) surya Forbes. - BIRKELUND : p.43 pl. 2, fig. 2
1976 Phylloceras (Hypophylloceras) mikobokense Forbes. - Kennedy & KLINGER : p.368 pl. 12, fig. 1
1985 Phylloceras (Hypophylloceras) surya Forbes. - Henderson & McNamara : p.42 pl. 1, figs. 7-8,11-12; pl. 2, figs. 1-2; text-fig. 2g (with full synonymy)
1986 Phylloceras (Hypophylloceras) surya Forbes. - Stinnesbeck : p.193 pl. 7, figs. 5-6
1992 Phylloceras (Neophylloceras) surya Forbes. - Kennedy & Henderson : p.391 pl. 1, figs. 1-7, 9, 13-14; pl. 15, fig. 4-5 (with additional synonymy)
1993 Phylloceras (Neophylloceras) surya Forbes. - Ward & Kennedy : p.16 figs. 17.13, 18.3, 18.4, 18.16, 18.17
1999 Phylloceras (Neophylloceras) surya Forbes. - FATMI & Kennedy : p.643 figs. 4.1-4.6, 15.3
2004 Hypophylloceras (Neophylloceras) sp. cf. surya Forbes. - Ifrim et al. : 5, 7 text-figs. 2c-e, 3a
Stratigraphy - relative ages:
Maastrichtian: Ifrim et al. (2004)
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. (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

Kossmat,F.. (1895):
Untersuchungen über die Südindische Kreideformation. Erster Theil . Beiträge zur Paläontologie Österreich-Ungarns und des Orient Vol. 9 p. 97-203

COLLIGNON,M.. (1956):
Ammonites neocretacees du Menabe (Madagascar) IV. - Les Phylloceratides; V. - Les Gaudryceratides; VI. - Les Tetragonitidae. . Annales Geologiques du Service des Mines de Madagascar Vol. 23 p. 1-106

BIRKELUND,T.. (1965):
Ammonites from the Upper Cretaceous of West Greenland . Meddeleser om Gronland Vol. 179 p. 1-192

Kennedy,W.J.. and KLINGER,H.C.. (1976):
Cretaceous faunas from Zululand and Natal, South Africa. The ammonite family Phylloceratidae . Bulletin of the British Museum (Natural History) Geology Vol. 27 p. 347-380

Henderson,R.A.. and McNamara,K.J.. (1985):
Maastrichtian non-heteromorph ammonites from the Miria Formation, Western Australia . Palaeontology Vol. 28 p. 35-88

Stinnesbeck,W.. (1986):
Zu den faunistischen und palökologischen Verhältnissen in der Quriquina Formation (Maastrichtium)Zentral-Chiles . Palaeontographica A194((4-6)) p. 99-237

Kennedy,W.J.. and Henderson,R.A.. (1992):
Non-heteromorph ammonites from the Upper Maastrichtian of Pondicherry, south India . Palaeontology Vol. 35 p. 381-442

Ward,P.D.. and Kennedy,W.J.. (1993):
Maastrichtian ammonites from the Biscay Region . Journal of Paleontology Vol. 67(5 II) p. 1-58

FATMI,A.N.. and Kennedy,W.J.. (1999):
Maastrichtian ammonites from Balochistan, Pakistan. . Journal of Paleontology Vol. 73(4) p. 641-662

Ifrim,C..; Stinnesbeck,W.. and López-Oliva,J.G.. (2004):
Maastrichtian cephalopods from Cerralvo, north-eastern Mexico . Palaeontology Vol. 47(6) p. 1575–1627

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