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Trichodinium scarburghensis
Trichodinium scarburghensis (Sarjeant, 1961) Williams et al., 1993
Originally Gonyaulax areolata (name illegitimate), subsequently Gonyaulacysta scarburghensis, thirdly Gonyaulacysta areolata (combination illegitimate), fourthly Acanthaulax areolata (combination illegitimate), fifthly Acanthaulax scarburghensis, sixthly Liesbergia scarburghensis, seventhly (and now) Trichodinium scarburghense.
Gonyaulacysta scarburghensis is the substitute name for Gonyaulax areolata Sarjeant, 1961a, p.95–96, pl.13, fig.13; text-fig.5 (an illegitimate name).
Taxonomic junior synonym: Acanthaulax senta, according to Berger (1986, p.343).
Holotype: Sarjeant, 1961, pl.13, fig.13, text-fig.5, Jan du Chene et al., 1986, pl.3, fig.1-2
Locus typicus: Scarborough Castle Cliff, England
Stratum typicum: Oxfordian
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Trichodinium scarburghense (Sarjeant, 1964b) Williams et al., 1993. Emended diagnosis from Sarjeant (1964b), ovoid theca with the tabulation ?4', 1a, 6", 6"’, ?1pv, 1"” and with a strong tapering apical horn rounded distally. The whole thecal surface, except the longitudinal and transverse furrow surfaces, is covered by low ridges so distributed as to form an irregular reticulate pattern. The thecal wall is very thin, consisting of two layers, the outer layer bearing or forming the ridges. The boundaries of plates and the margins of furrows bear low, alveolate crests. The longitudinal furrow extends from the base of the apical horn to the antapex. It is narrow and of relatively constant width. The transverse furrow is very narrow, forming a laevorotatory spiral such that its two ends differ in antero-posterior position by about three times its width. Archeopyle apical. Size: overall length 120-170µm. Holotype: length 155 µm, width 125 µm, horn length 25 µm, transverse furrow width ca 10 µm, longitudinal furrow width ca 5 µm.
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Original diagnosis: Sarjeant, 1961, p.95: Gonyaulax areolata
A species of fossil Gonyaulax with an ovoid theca having the tabulation ?', 1a, 6", 6''', ?1p, 1'''' and with a strong, tapering apical horn rounded at its extremity. The whole thecal surface except the longitudinal and transverse furrows is covered by low ridges forming an irregular reticulate patterning; the thecal wall is very thin but consists of two layers, the outer bearing the ridges. The boundaries of plates and the furrow margins bear low alveolate crests. The longitudinal furrow extends from apex to antapex; it is narrow, as the transverse furrow.
Original description: Sarjeant, 1961, p.96: Gonyaulax areolata
Theca yellowish. Tabulation not easily discerned and a composite text-figure therefore given. Apical tabulation obscure. An anterior intercalary plate clearly present, plus six pre-equatorial plates, of which the first (1") is reduced. Transverse furrow extends around theca in a strong laevo-rotatory spiral such that its two ends differ in antero-posterior position by approximately three times the furrow's width. Six postequatorial plates certainly present; a posterior intercalary plate appears present but could not be definitely confirmed. No posterior ventral plates present, longitudinal furrow extending to polygonal antapical plate. Surface reticulation of ridges dense; fields delimited by these ridges always small, not regularly polygonal but varying considerably in relative size and shape. Reticulation extending on to apical horn but absent from furrows. Crests consist of linked processes (links sometimes broken) arising from sutures, their points of origin corresponding with junctions of ridges with sutures.
Dimensions: Holotype: Overall length 155 µm, length of horn 25 µm, overall breadth 125 µm; transverse furrow c. 10 µm wide, longitudinal furrow c. 5 µm wide. Range: overall length 120 - 170 µm, relative proportions being fairly constant.
Originally Gonyaulax areolata (name illegitimate), subsequently Gonyaulacysta scarburghensis, thirdly Gonyaulacysta areolata (combination illegitimate), fourthly Acanthaulax areolata (combination illegitimate), fifthly Acanthaulax scarburghensis, sixthly Liesbergia scarburghensis, seventhly (and now) Trichodinium scarburghense.
Gonyaulacysta scarburghensis is the substitute name for Gonyaulax areolata Sarjeant, 1961a, p.95–96, pl.13, fig.13; text-fig.5 (an illegitimate name).
Taxonomic junior synonym: Acanthaulax senta, according to Berger (1986, p.343).
Holotype: Sarjeant, 1961, pl.13, fig.13, text-fig.5, Jan du Chene et al., 1986, pl.3, fig.1-2
Locus typicus: Scarborough Castle Cliff, England
Stratum typicum: Oxfordian
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Trichodinium scarburghense (Sarjeant, 1964b) Williams et al., 1993. Emended diagnosis from Sarjeant (1964b), ovoid theca with the tabulation ?4', 1a, 6", 6"’, ?1pv, 1"” and with a strong tapering apical horn rounded distally. The whole thecal surface, except the longitudinal and transverse furrow surfaces, is covered by low ridges so distributed as to form an irregular reticulate pattern. The thecal wall is very thin, consisting of two layers, the outer layer bearing or forming the ridges. The boundaries of plates and the margins of furrows bear low, alveolate crests. The longitudinal furrow extends from the base of the apical horn to the antapex. It is narrow and of relatively constant width. The transverse furrow is very narrow, forming a laevorotatory spiral such that its two ends differ in antero-posterior position by about three times its width. Archeopyle apical. Size: overall length 120-170µm. Holotype: length 155 µm, width 125 µm, horn length 25 µm, transverse furrow width ca 10 µm, longitudinal furrow width ca 5 µm.
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Original diagnosis: Sarjeant, 1961, p.95: Gonyaulax areolata
A species of fossil Gonyaulax with an ovoid theca having the tabulation ?', 1a, 6", 6''', ?1p, 1'''' and with a strong, tapering apical horn rounded at its extremity. The whole thecal surface except the longitudinal and transverse furrows is covered by low ridges forming an irregular reticulate patterning; the thecal wall is very thin but consists of two layers, the outer bearing the ridges. The boundaries of plates and the furrow margins bear low alveolate crests. The longitudinal furrow extends from apex to antapex; it is narrow, as the transverse furrow.
Original description: Sarjeant, 1961, p.96: Gonyaulax areolata
Theca yellowish. Tabulation not easily discerned and a composite text-figure therefore given. Apical tabulation obscure. An anterior intercalary plate clearly present, plus six pre-equatorial plates, of which the first (1") is reduced. Transverse furrow extends around theca in a strong laevo-rotatory spiral such that its two ends differ in antero-posterior position by approximately three times the furrow's width. Six postequatorial plates certainly present; a posterior intercalary plate appears present but could not be definitely confirmed. No posterior ventral plates present, longitudinal furrow extending to polygonal antapical plate. Surface reticulation of ridges dense; fields delimited by these ridges always small, not regularly polygonal but varying considerably in relative size and shape. Reticulation extending on to apical horn but absent from furrows. Crests consist of linked processes (links sometimes broken) arising from sutures, their points of origin corresponding with junctions of ridges with sutures.
Dimensions: Holotype: Overall length 155 µm, length of horn 25 µm, overall breadth 125 µm; transverse furrow c. 10 µm wide, longitudinal furrow c. 5 µm wide. Range: overall length 120 - 170 µm, relative proportions being fairly constant.