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Alterbidinium recticorne
Alterbidinium recticorne, (Vozzhennikova, 1967), Harker and Sarjeant in Harker et al., 1990
Originally Albertia (generic name illegitimate), subsequently Alterbia (combination illegitimate), thirdly Alterbidinium.
Taxonomic senior synonym: Deflandrea (now Alterbidinium) acutula, according to Whitney (1979, p.125) and Lentin and Williams (1993, p.14).
[Discussion (holotype): The nomenclatural type of the genus Alterbidinium remains the holotype of Alterbidinium recticorne. Vozzhennikova (1967, p.151) designated the holotype by means of a "preparation" number and reference to her pl.77, figs.1–2. However, these two illustrations are of different specimens. I.C.N. Article 43.3 indicates that for fossils prior to 2001, holotype designation does not need to be tied directly to a particular figure and hence this species name was validly published by Vozzhennikova (1967). Stover and Evitt (1978, p.93) designated the specimen illustrated in Vozzhennikova (1967, pl.77, fig.1) as lectotype. However, Lentin and Vozzhennikova (1990, p.32) implied that the originally intended holotype is the specimen illustrated in Vozzhennikova (1967, pl.77, fig.2); so the latter must supersede Stover and Evitt's lectotype designation.]
Holotype: Vozzhennikova, 1967, pl.77, figs.1-2 (different specimens) and Lentin and Vozzhennikova, 1990, pl.3, fig.10; text-fig.13b? (see discussion below)
Lectotype: Vozzhennikova, 1967, pl.77, fig.1; designated by Stover and Evitt, 1978.
Locus typicus: Kazakhstan (Kustanai)
Age: Turonian.
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Original description as Albertia recticorne: [Vozzhennikova, 1967, p.151-152]:
Diagnosis:
Epitheca triangular, with straight slightly convex or somewhat concave lateral walls and with a short, slender apical horn bluntly rounded at the tip. Hypotheca trapeziform, with one long and one short antapical horn both of which are acutely pointed. The short horn is often absent and where it would occur the hypotheca is rounded or truncated.
Transverse furrow shallow, equatorial, annulate, from its ends the longitudinal furrow runs towards the antapex.
Internal body broadly rhomboid or similar in form to the theca, thin walled, with a smooth or finely granular surface. Thecal surface smooth or finely granular. Pylome triangular, its angles rounded or bluntly truncated.
Dimensions:
Holotype: length of theca 91.8 µm, breadth 54.0 µm, width of transverse furrow 5.4 µm, length of internal body 56.7 µm, breadth 45.0 µm.
Originally Albertia (generic name illegitimate), subsequently Alterbia (combination illegitimate), thirdly Alterbidinium.
Taxonomic senior synonym: Deflandrea (now Alterbidinium) acutula, according to Whitney (1979, p.125) and Lentin and Williams (1993, p.14).
[Discussion (holotype): The nomenclatural type of the genus Alterbidinium remains the holotype of Alterbidinium recticorne. Vozzhennikova (1967, p.151) designated the holotype by means of a "preparation" number and reference to her pl.77, figs.1–2. However, these two illustrations are of different specimens. I.C.N. Article 43.3 indicates that for fossils prior to 2001, holotype designation does not need to be tied directly to a particular figure and hence this species name was validly published by Vozzhennikova (1967). Stover and Evitt (1978, p.93) designated the specimen illustrated in Vozzhennikova (1967, pl.77, fig.1) as lectotype. However, Lentin and Vozzhennikova (1990, p.32) implied that the originally intended holotype is the specimen illustrated in Vozzhennikova (1967, pl.77, fig.2); so the latter must supersede Stover and Evitt's lectotype designation.]
Holotype: Vozzhennikova, 1967, pl.77, figs.1-2 (different specimens) and Lentin and Vozzhennikova, 1990, pl.3, fig.10; text-fig.13b? (see discussion below)
Lectotype: Vozzhennikova, 1967, pl.77, fig.1; designated by Stover and Evitt, 1978.
Locus typicus: Kazakhstan (Kustanai)
Age: Turonian.
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Original description as Albertia recticorne: [Vozzhennikova, 1967, p.151-152]:
Diagnosis:
Epitheca triangular, with straight slightly convex or somewhat concave lateral walls and with a short, slender apical horn bluntly rounded at the tip. Hypotheca trapeziform, with one long and one short antapical horn both of which are acutely pointed. The short horn is often absent and where it would occur the hypotheca is rounded or truncated.
Transverse furrow shallow, equatorial, annulate, from its ends the longitudinal furrow runs towards the antapex.
Internal body broadly rhomboid or similar in form to the theca, thin walled, with a smooth or finely granular surface. Thecal surface smooth or finely granular. Pylome triangular, its angles rounded or bluntly truncated.
Dimensions:
Holotype: length of theca 91.8 µm, breadth 54.0 µm, width of transverse furrow 5.4 µm, length of internal body 56.7 µm, breadth 45.0 µm.