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Alterbia recticornis
Alterbia recticornis, (Vozzhennikova, 1967), Lentin and Williams, 1976
Combination illegitimate: the generic name Alterbia is illegitimate.
Originally Albertia (an illegitimate generic name), subsequently Alterbia (combination illegitimate), thirdly Alterbidinium.
Vozzhennikova"s illustrations represent two different specimens. Accordingly, Stover and Evitt, 1978, designated as lectotype the specimen illustrated in Vozzhennikova, 1967, pl.77, fig.1.
Lentin and Williams, 1981, did not accept Stover and Evitt"s 1978 contention that Vozzhennikova had not validly published this species. Lentin and Williams (1981) argued that Vozzhennikova designated a holotype, which she illustrated in two views (her pl.77, figs.1-2); thus, the designation of a lectotype by Stover and Evitt, 1978, was unnecessary. However, re-examination of Vozzhennikova"s original material demonstrates that Stover and Evitt, 1978, were correct. This species, the original type of the genus Alterbia, was considered to be a taxonomic junior synonym of Alterbia acutula (Wilson, 1967b) Lentin and Williams, 1976, by Whitney, 1979. Alterbia acutula therefore became the correct name for the type species of Alterbia, but the nomenclatural type of the genus remained the holotype of Alterbia recticornis. Harker and Sarjeant in Harker et al., 1990, retained Alterbia (as Alterbidinium) recticornis as a separate species. Lentin and Williams, 1993, followed Lentin and Vozzhennikova, 1990, and Khowaja-Ateequzzaman et al., 1991, in regarding Alterbia (as Alterbidinium) recticornis as a taxonomic junior synonym of Alterbidinium (as Alterbia) acutulum, Wilson, 1967 Lentin and Williams, 1985.
Taxonomic senior synonym: Deflandrea (now Alterbidinium) acutula, according to Whitney (1979, p.125) and Lentin and Williams (1993, p.14). The nomenclatural type of the genus Alterbia remains the holotype of Alterbia recticornis.
Holotype: Vozzhennikova, 1967, pl.77, figs.1-2 (different specimens) and Lentin and Vozzhennikova, 1990, pl.3, fig.10; text-fig.13b?
Lectotype: Vozzhennikova, 1967, pl.77, fig.1; designated by Stover and Evitt, 1978
Locus typicus: Kazakhstan (Kustanai)
Stratum typicum: 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.
Combination illegitimate: the generic name Alterbia is illegitimate.
Originally Albertia (an illegitimate generic name), subsequently Alterbia (combination illegitimate), thirdly Alterbidinium.
Vozzhennikova"s illustrations represent two different specimens. Accordingly, Stover and Evitt, 1978, designated as lectotype the specimen illustrated in Vozzhennikova, 1967, pl.77, fig.1.
Lentin and Williams, 1981, did not accept Stover and Evitt"s 1978 contention that Vozzhennikova had not validly published this species. Lentin and Williams (1981) argued that Vozzhennikova designated a holotype, which she illustrated in two views (her pl.77, figs.1-2); thus, the designation of a lectotype by Stover and Evitt, 1978, was unnecessary. However, re-examination of Vozzhennikova"s original material demonstrates that Stover and Evitt, 1978, were correct. This species, the original type of the genus Alterbia, was considered to be a taxonomic junior synonym of Alterbia acutula (Wilson, 1967b) Lentin and Williams, 1976, by Whitney, 1979. Alterbia acutula therefore became the correct name for the type species of Alterbia, but the nomenclatural type of the genus remained the holotype of Alterbia recticornis. Harker and Sarjeant in Harker et al., 1990, retained Alterbia (as Alterbidinium) recticornis as a separate species. Lentin and Williams, 1993, followed Lentin and Vozzhennikova, 1990, and Khowaja-Ateequzzaman et al., 1991, in regarding Alterbia (as Alterbidinium) recticornis as a taxonomic junior synonym of Alterbidinium (as Alterbia) acutulum, Wilson, 1967 Lentin and Williams, 1985.
Taxonomic senior synonym: Deflandrea (now Alterbidinium) acutula, according to Whitney (1979, p.125) and Lentin and Williams (1993, p.14). The nomenclatural type of the genus Alterbia remains the holotype of Alterbia recticornis.
Holotype: Vozzhennikova, 1967, pl.77, figs.1-2 (different specimens) and Lentin and Vozzhennikova, 1990, pl.3, fig.10; text-fig.13b?
Lectotype: Vozzhennikova, 1967, pl.77, fig.1; designated by Stover and Evitt, 1978
Locus typicus: Kazakhstan (Kustanai)
Stratum typicum: Turonian
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
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.