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Andalusiella ivoirensis

Andalusiella ivoirensis Masure, Tea and Yao, 1996

Holotype: Masure, Tea and Yao, 1996: Plate I, l, 2; Fig. 3
Paratype: Masure, Tea and Yao, 1996: Plate I, 4-6
Type locality: Gazelle well, offshore Ivory Coast sedimentary basin.
Stratigraphic horizon: Maastrichtian.

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Original description: [Masure, Tea and Yao, 1996, p. 177-180]:

Diagnosis:
Proximate, acrocavate dinoflagellate cyst, with rhomboidal to ovoidal central body, long apical horn and two unequal antapical horns, the left one markedly longer than the right one. Wall composed of a periphragm and of an endophragm separated only in the horns, in close contact on the central body. Brown endophragm with thickenings at the base of the horns.
Peridinioid paratabulation indicated by parasutural features and archeopyle.
Paratabulation formula: 1-2? pr, 4", 3a, 7", 4-5c, 5"", 2"", Xs, ps.
Parasutural septa delineated paratabulation of ortho/hexa type (Evitt, 1985).
Parasulcus exhibits a flagellar scar. Paracingulum possesses 4-5 cingular paraplates.
Intercalary archeopyle of I/I type, standard 2a hexa, isodeltaform. Operculum free, occasionaly adherent.


Description:
Shape: cyst proximate with elongate ellipsoidal central body, long apical horn and two unequal antapical horns. Antapical horns have a common base and are close together near the longitudinal axis, left horn markedly longer than the thorn-reduced right one.
Wall relationship: endophragm and periphragm. Periphragm thin, smooth, chagrinate, colorless; endophragm thick, dense with a rich brown colour. Periphragm and endophragm in close contact on the central body. Periphragm developed apical and antapical horns. Endophragm extends up to half-length or higher into the horns, acrocavate cyst. The "darkened ring" (epistomia) at the horn bases consists of thickening of the endophragm.
Wall features: endophragm and periphragm with parasutural septa. Crests of the septa smooth.
Peridinioid paratabulation.
Epicyst: on ventral face, 1" with ortho style of Steidinger and Williams ( 1970, p. 13), narrow 2" and 4" apical paraplates; on dorsal face, paraplate 2a with hexa type (isodeltaform) of Lentin and Williams, 1975.
Hypocyst: antapical paraplates 1"", 2"" well developed and displaced to the dorsal face. Postcingular paraplates 2"", 3"" and 4"" shorter than 1"" and 5"" paraplates.
Paracingulum: descending, slightly helicoidal, indicated by an equatorial depression and parasutural septa, possesses 4-5 paraplates.
Parasulcus: indicated by a poorly delimited longitudinal depression and a well developed flagellar bean-shaped scar. Postsulcal, ps, paraplate well-developed and contact 1""/ps shorter than contact 5""/ps.
Archeopyle: intercalary, type I/I, 2a only, isodeltaform. Operculum monoplacoid free, occasionally adherent.

Dimensions:
Holotype: total length 132 µm; central body: length 96 µm, width 78 µm; length apical horn: 25 µm; length antapical horns: left 11 µm, right 5 µm; parasutural septa: height 0.9 µm.
Paratype: total length 132 µm; central body: length 86 µm, width 71 µm; length apical horn: 29 µm; length of antapical horns: left 17 µm, right (unobservable); parasutural septa: height 0.8 µm.
Range of twelve specimens measured. Total length: 224 (126) 118 µm; central body: length 105 (92) 82µm, width 84 (72) 63 µm; apical horn 66 (38) 24 µm; length of antapical horns: left 53 (23) 14 µm, right 8-2 µm; parasutural septa: height 0.8-1.2 µm.
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