Anagaudryceras politissimum Kossmat 1895 from: Ward, P.D..Kennedy, W.J.. (1993): Maastrichtian Ammonites from the Biscay Region (France, Spain) . Memoir (The Paleontological Society), Journal of Paleontology34 (Supplement to Vol. 67)(5) p. 1-58 . |
Notice: This catalogue page may contain unedited data.
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Species Anagaudryceras politissimum Kossmat 1895 |
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[1] text-fig. 3i-j Ifrim et al. (2004) [2] text-fig. 6d-e,i Ifrim et al. (2004)
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Diagnosis / Definition: |
Ifrim et al. (2004):
Description: Initia1 whor1s are serpenticone, with trapezoida1 whorl section and low expansion rate. The broad, flat venter bends narrow1y into short flanks that are not separated from the flat umbilica1 wa11s.WB/WH is c. 1·6, but most specimens are crushed. Nine to ten flat bullae per half whorl are present. Beginning at diameters of 7 mm whorl height increases and the whorl section gradually changes from trapezoidal to rounded. Coiling is evolute with little overlap of whorls, although overlap increases with growth. Expansion rate of the shell is low, but increases during ontogeny, thus resulting in a lower WB/WH ratio and smaller umbilicus. Two or more constrictions are present per whorl and accompanied by prominent ribs that are convex on the umbilical shoulder, but projected on the flank and venter. Suture line is finely incised with an extended median saddle and biphylloid terminations ofE/L und LlU2 saddles. Umbilical
lobes are extended early on and complex, but do not increase in number.
FATMI & Kennedy (1999):
Description.-GSP 1038: wholly septate, partially exfoliated, maximum preserved diameter 53.5mm. Coiling moderately evolute with U = 27.5 percent (Table 2). Umbilical wall broadly convex, whorl section compressed with whorl breadth to height ratio of 0.95, inner to mid-flanks flattened, outer flanks convergent, ventrolateral shoulders and venter broadly rounded. The partially exfoliated shell and internal mould are smooth but for traces of growth lines and striae. A single feeble constriction at 40 mm diameter approximately is feebly prorsiradiate, lacking collar-ribs. Partially exposed suture deeply and intricately subdivided. Type.-The holotype, by monotypy, is the original of Kossmat, 1895, p. 128(32), plate 15(l), figure 7, from the upper part of the Trichinopoly Group of Varagur, south India.
Ward & Kennedy (1993):
Description. -
Specimens crushed, and up to estimated 90-
100 mm diameter. Coiling very evolute, whorls only slightly
overlapping, inner whorls serpenticone, and slowly expanding.
Expansion rate increases on outer whorls so that umbilicus becomes
relatively smaller. Where well preserved, surface of mold
covered in fine, dense lirae, most obvious on ventrolateral
shoulders and venter. Four, perhaps five, prominent collars per
whorl, followed by weak constriction. Lirae, collars, and constrictions
parallel, prorsiradiate, and feebly flexuous, convex on
umbilical shoulder and inner flank, concave on outer flank and
projected forwards on ventrolateral shoulder to cross venter in
broad convexity. |
Discussion / Comments: |
Ifrim et al. (2004):
Remarks: Initial whorls with trapezoidal whorl section resemble oaudryceras kayei and Zelandites varuna.
Anagaudryceras politissimum resembles G. kayei though all growth stages although there are clear
differences. Gaudryceras kayei is characterized by a lower expansion rate, higher number of whorls at
similar diameters and stronger ornament. The conch of A. politissimum inflates at a smaller growth stage
than G. kayei.
Occurrence: Turonian-Santonian of southern India (Kossmat 1895), Santonian of Zululand (Kennedy and Klinger
1979), and Maastrichtian of Madagascar (Collignon 1956). In western Australia (Henderson and McNamara 1985),
Chile (Stinnesbeck 1986, 1996) and the Biscay region (Ward and Kennedy 1993) this species was recorded to range
high in the Upper Maastrichtian A. mayaroensis Zone.
FATMI & Kennedy (1999):
Discussion.-The present rather featureless specimen closely resembles the holotype, if a little less compressed. It lacks the collars associated with constrictions shown by comparably-sized individuals from the Maastrichtian of the Biscay region of southeast France (Ward and Kennedy, 1993), and western Australia (Henderson and McNamara, 1985). Matsumoto (1995) referred to the species specimens from the Coniacian of Hokkaido, Japan, that develop narrow fold ribs on body chambers at whorl heights of as little as 18 mm, and possibly less. This feature is not developed in the much larger holotype, or Biscay individuals up to an estimated 110 mm in diameter, and we doubt that the Japanese material is conspecific with the present specimen and other similar individuals.
Ward & Kennedy (1993):
Type species.-
Ammonites Sacya Forbes, 1846, p. 113, Pl.
14, fig. 9; by original designation by Shimizu, 1934, p. 67; =Ammonites
Buddha Forbes, 1846, p. 112, P1. 14, fig. 9.
Type.-
Holotype is the original of Kossmat, 1895, Pl. 15(1),
fig. 7, from the upper Trichinopoly Group of Varagur, south
India.
Discussion.-
See Howarth (1965) and Kennedy and Klinger
(1979) for a discussion of this species, which is differentiated
from others on criteria such as relative proportions and frequency
of constrictions.
Occurrence.-
In the Biscay sections this taxon ranges from
the middle of Member I (lower Maastrichtian) to near the base
of Member V (upper Maastrichtian). At Hendaye, a fragment
possibly referrable to this species has been found within 1 m of
the K-T boundary. Elsewhere, the species ranges from the Turonian
to Santonian of south India, Santonian of Zululand,
Maastrichtian of Madagascar and western Australia.
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Systematics: |
36 Ordo Ammonoidea
Subordo Lytoceratina
Superfamilia Tetragonitaceae
Familia Gaudryceratidae
Genus Anagaudryceras
Species Anagaudryceras politissimum
38 Ordo Ammonoidea
Subordo Lytoceratina
Superfamilia Tetragonitaceae
Familia Gaudryceratidae
Genus Pseudophyllites
Species Anagaudryceras politissimum
Species Pseudophyllites indra
40 Ordo Ammonoidea
Subordo Phylloceratina
Superfamilia Phyllocerataceae
Subfamilia Phylloceratinae
Genus Anagaudryceras
Species Anagaudryceras politissimum
47 Ordo Ammonoidea
Subordo Lytoceratina
Superfamilia Tetragonitaceae
Familia Gaudryceratidae
Genus Anagaudryceras
Species Anagaudryceras politissimum
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Synonym list: |
Ifrim et al. (2004):
FATMI & Kennedy (1999):
Ward & Kennedy (1993):
1934 Paragaudryceras Shimizu. - SHIMIZU :
1972 Murphyella Matsumoto. - Matsumoto :
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Stratigraphy - relative ages: |
? middle Campanian, lower Campanian - lower Campanian, ? upper Santonian: Ifrim et al. (2004)
upper Maastrichtian - lower Maastrichtian: Ward & Kennedy (1993)
upper Maastrichtian - Turonian: FATMI & Kennedy (1999)
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References: |
Kossmat,F.. (1895): Untersuchungen,über die Südindische Kreideformation. Beitrage zur Palaontologie Osterreich-Ungarns und des Orients . Vol. 9 p. 97-203 (1-107)
Kossmat,F.. (1895): Untersuchungen über die Südindische Kreideformation. Erster Theil . Beiträge zur Paläontologie Österreich-Ungarns und des Orient Vol. 9 p. 97-203
Kossmat,F.. (1895): 1895-1898. Untersuchungen Ober die Sudindische Kreideformation. . Beiträge zur Paleontologie Österreich-Ungarns und des Orients. p. 9 (1895):97-203
SHIMIZU,S.. (1934): Ammonites. In: Cephalopoda, Iwanami's lecture series of Geology and Palaeontology [In Japanese] Eds: SHIMIZU, S..OBATA, T.. p. 137 pp
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
COLLIGNON,M.. (1971): Atlas des fossiles caracteristiques de Madagascar (Ammonites)(Maestrichtian). Vol. 17 p. 82
Matsumoto,T.. (1972): A new gaudryceratine ammonite from Hokkaido . Memoirs of the Faculty of Science, Kyushu University, Series D, Geology Vol. 21 p. 207-215
Kennedy,W.J.. and KLINGER,H.C.. (1979): Cretaceous faunas from Zululand and Natal, South Africa. The ammonite family Gaudryceratidae. . Bulletin of the British Museum (Natural History ) Geology Vol. 31 p. 121-173
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
Ward,P.D.. and Kennedy,W.J.. (1993): Maastrichtian Ammonites from the Biscay Region (France, Spain) . Memoir (The Paleontological Society), Journal of Paleontology34 (Supplement to Vol. 67)(5) p. 1-58
Ward,P.D.. and Kennedy,W.J.. (1993): Maastrichtian ammonites from the Biscay Region . Journal of Paleontology Vol. 67(5 II) p. 1-58
Matsumoto,T.. (1995): Notes on gaudryceratid ammonites from Hokkaido and Sakhalin. . Palaeontological Society of Japan Special Paper Vol. 35 p. 152 p.
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
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