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Bitectatodinium tepikiense
From Fensome et al., 2019:
Bitectatodinium tepikiense Wilson, 1973, p.351,353, fig.2, nos.1–12. Holotype: Wilson, 1973, fig.2, nos.1–4. Taxonomic junior
synonym: Caledonidinium vermiculatum, according to Harland (1977b, p.93). Motile equivalent: Gonyaulax
spinifera (Claparède and Lachmann, 1859) Diesing, 1866, according to Dale (1976, table 2 — p.45), and Gonyaulax
digitale (Pouchet) Kofoid according to Lewis et al. (2001). Age: Middle Pleistocene.
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Original description: [Wilson, 1973, p. 351-353]:
Description:
Tract spherical and fairly thick-walled (thickness 2-4 µm). Wall bilayered with a thin dense inner layer and thicker spongy microreticulate outer layer; in surface view the texture appears irregularly granulate (Fig. 2, no. 4).
Archeopyle large, precingular, and formed from two adjacent plates; a small tooth-like medial projection usually present on upper margin of archeopyle (fig. 2, no. 1-7); archeopyle narrowest towards apex and broadest near cingular margin. Both opercular plates usually occur separated both from parent cyst and from each other.
Atabulate; cingulum typically absent.
Dimensions:
Holotype: overall diameter 51 µm, wall thickness 2.5 µm, maximum breadth of archeopyle 41 µm. Range of 40 measured specimens: overall diameter 46(53)60 µm, wall thickness 2-4 µm.
Affinities:
Specimens are frequently folded or split and may easily be confused with certain pollen species, particularly since the characteristic archeopyle of B. tepikiense is not always apparent in folded or broken specimens. Pollen grains of the extant New Zealand conifer Agathis australis (Kauri) superficially resemble B. tepikiense, both in size and general morphology. Although the 2-plate archeopyle distinguishes B. tepikiensefrom species of Tectatodinium Wall, confusion could arise if the nature of the archeopyle is unclear. Detached opercula, which almost invariably occur as single plates, are apparently indistinguishable from those of Tectatodinium. The size and shape of the archeopyle of B. tepikiense indicate that it is probably from reflected plates 2'' and 3''.
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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999
Bitectatodinium tepikiense Wilson, 1973. This species has a 2P archeopyle resulting from the loss of 2" and 3". Wall fairly thick, 2-4 µm, with dense inner layer and thicker spongy microreticulate outer layer, which in surface view appears granular.
Size: overall 46-60 µm.
Bitectatodinium tepikiense Wilson, 1973, p.351,353, fig.2, nos.1–12. Holotype: Wilson, 1973, fig.2, nos.1–4. Taxonomic junior
synonym: Caledonidinium vermiculatum, according to Harland (1977b, p.93). Motile equivalent: Gonyaulax
spinifera (Claparède and Lachmann, 1859) Diesing, 1866, according to Dale (1976, table 2 — p.45), and Gonyaulax
digitale (Pouchet) Kofoid according to Lewis et al. (2001). Age: Middle Pleistocene.
---------------------------------------------------------------------------------------------------
Original description: [Wilson, 1973, p. 351-353]:
Description:
Tract spherical and fairly thick-walled (thickness 2-4 µm). Wall bilayered with a thin dense inner layer and thicker spongy microreticulate outer layer; in surface view the texture appears irregularly granulate (Fig. 2, no. 4).
Archeopyle large, precingular, and formed from two adjacent plates; a small tooth-like medial projection usually present on upper margin of archeopyle (fig. 2, no. 1-7); archeopyle narrowest towards apex and broadest near cingular margin. Both opercular plates usually occur separated both from parent cyst and from each other.
Atabulate; cingulum typically absent.
Dimensions:
Holotype: overall diameter 51 µm, wall thickness 2.5 µm, maximum breadth of archeopyle 41 µm. Range of 40 measured specimens: overall diameter 46(53)60 µm, wall thickness 2-4 µm.
Affinities:
Specimens are frequently folded or split and may easily be confused with certain pollen species, particularly since the characteristic archeopyle of B. tepikiense is not always apparent in folded or broken specimens. Pollen grains of the extant New Zealand conifer Agathis australis (Kauri) superficially resemble B. tepikiense, both in size and general morphology. Although the 2-plate archeopyle distinguishes B. tepikiensefrom species of Tectatodinium Wall, confusion could arise if the nature of the archeopyle is unclear. Detached opercula, which almost invariably occur as single plates, are apparently indistinguishable from those of Tectatodinium. The size and shape of the archeopyle of B. tepikiense indicate that it is probably from reflected plates 2'' and 3''.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999
Bitectatodinium tepikiense Wilson, 1973. This species has a 2P archeopyle resulting from the loss of 2" and 3". Wall fairly thick, 2-4 µm, with dense inner layer and thicker spongy microreticulate outer layer, which in surface view appears granular.
Size: overall 46-60 µm.