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Meiourogonyaulax bathonica
Meiourogonyaulax bathonica (Conway, 1978, p.349, pl.2, figs.4–5;7–8) Fensome and Williams, 2004, p.421.
Originally Lithodinia, subsequently (and now) Meiourogonyaulax.
This combination was not validly published in Conway (1990, p.32) since that author did not fully reference the basionym.
Holotype: Conway, 1978, pl.2, figs.4–5.
Age: late Bathonian.
Original description (Conway, 1978)
Lithodinia bathonica n. sp. (Plate II, 4--5, 6--7)
Type locality: Holotype --Slide MS 27, England finder co-ordinates T12, Sample 7, Yinnon 1 borehole, Core 9 (2488--2504 m), Box 9 (very base),Late Bathonian. Paratype 1 -- Slide MS 13, England finder co-ordinates J41, Sample 4, Zohar 5 borehole, Core 9 (1190--1197 m), Box 7 (very base), Zohar Formation, Late Bathonian.
Paratype 2 -- Slide MS 3, England finder co-ordinates P22/1, Sample 15, Zohar 5 borehole, Core 9 (1190--1197 m), Box 8 (top), Zohar Formation, Late Bathonian.
Derivation of name: The species name is derived from the age of the formation in which the holotype was found. Description: The cysts are of the proximate type, and have an apical archaeopyle which is formed by the loss of all the apical plates. Deep accessory archaeopyle sutures are developed between the precingular plates along the line of detachment. The ambitus is round to ovoid. The tabulation formula is ?4' 6" 6c 6'" 1'"'. Low ragged spinose crests mark the plate boundaries.They are 2 µm high, and bear capitate spines which are usually linked by trabeculae. The cingulum and sulcus are similarly delineated. The cingulum is laevorotatory, about 4 pm across, and diVides the test into equal parts. The sulcus is 5 µm across at the equator, and extends from the antapical pole to the principal archaeopyle suture. The test is coarsely granulate to papillate .The papillae may become dense, giving a pseudo-reticulate appearance. Capitate spines, up to 5 µm high, are developed at the antapex. Dimensions: Overall length 58--69 µm (8 specimens); length (minus apex)
47--59 µm (10 specimens); breadth 39--59 µm (10 specimens). Remarks: These cysts are unlike any previously described. Lithodinia sp. described from this borehole is similar, but differs in size, and by having more prominent crests whose spines are not linked distally.
Originally Lithodinia, subsequently (and now) Meiourogonyaulax.
This combination was not validly published in Conway (1990, p.32) since that author did not fully reference the basionym.
Holotype: Conway, 1978, pl.2, figs.4–5.
Age: late Bathonian.
Original description (Conway, 1978)
Lithodinia bathonica n. sp. (Plate II, 4--5, 6--7)
Type locality: Holotype --Slide MS 27, England finder co-ordinates T12, Sample 7, Yinnon 1 borehole, Core 9 (2488--2504 m), Box 9 (very base),Late Bathonian. Paratype 1 -- Slide MS 13, England finder co-ordinates J41, Sample 4, Zohar 5 borehole, Core 9 (1190--1197 m), Box 7 (very base), Zohar Formation, Late Bathonian.
Paratype 2 -- Slide MS 3, England finder co-ordinates P22/1, Sample 15, Zohar 5 borehole, Core 9 (1190--1197 m), Box 8 (top), Zohar Formation, Late Bathonian.
Derivation of name: The species name is derived from the age of the formation in which the holotype was found. Description: The cysts are of the proximate type, and have an apical archaeopyle which is formed by the loss of all the apical plates. Deep accessory archaeopyle sutures are developed between the precingular plates along the line of detachment. The ambitus is round to ovoid. The tabulation formula is ?4' 6" 6c 6'" 1'"'. Low ragged spinose crests mark the plate boundaries.They are 2 µm high, and bear capitate spines which are usually linked by trabeculae. The cingulum and sulcus are similarly delineated. The cingulum is laevorotatory, about 4 pm across, and diVides the test into equal parts. The sulcus is 5 µm across at the equator, and extends from the antapical pole to the principal archaeopyle suture. The test is coarsely granulate to papillate .The papillae may become dense, giving a pseudo-reticulate appearance. Capitate spines, up to 5 µm high, are developed at the antapex. Dimensions: Overall length 58--69 µm (8 specimens); length (minus apex)
47--59 µm (10 specimens); breadth 39--59 µm (10 specimens). Remarks: These cysts are unlike any previously described. Lithodinia sp. described from this borehole is similar, but differs in size, and by having more prominent crests whose spines are not linked distally.