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Spiniferella cornuta subsp. kasira
Spiniferella cornuta subsp. kasira Slimani et al., 2012, p.344, fig.4K–T.
Holotype: Slimani et al., 2012, fig.4M–O.
Age: early Danian.
Original description (Slimani et al., 2012):
Spiniferella cornuta subsp. kasira subsp. nov. (Fig. 4K–T)
2010 Spiniferella sp. cf. Spiniferites sp. A of Kirsch (1991); Slimani et al. p. 99, pl. 2, fig. 2.
Holotype. Sample OH 12, slide 2, England Finder E46 (Fig. 4M–O).
Type locality and bed. Ouled Haddou section, north of Taza, northern Morocco; clayey marl 35 cm above the K/T boundary, lower Danian.
Etymology. From ‘kasir’ (Arabic): short, with reference to the very short processes and the apical horn.
Diagnosis. A species of Spiniferella with a granular surface, short processes and a distinct apical horn. Operculum mostly free.
Description. The proximate to proximochorate dinoflagellate cyst has an ovoid central body. The wall of the cornucavate cyst consists of a granular endophragm with a maximum thickness of 1 µm and a thin (0.5 µm) smooth to slightly granular periphragm (Fig. 4N, P, S). The periphragm forms a small but distinct apical horn. The horn is hollow, broad-based and tapers distally to a blunt or truncated distal end (Fig. 4M, P). The processes are short (maximum 5 µm long). The sutural processes are distally bifid to weakly bifurcate (Fig. 4L, N). The gonal processes are generally slightly longer than the sutural processes and are discretely bifurcate or trifurcate (Fig. 4N, R, S). The sutural septa are of low height and generally concave between processes. The observed gonyaulacoid tabulation is that of Spiniferella and is indicated by the processes, septa and archeopyle.
Dimensions:
Holotype: central body length, 43 µm; central body width, 40 µm; apical horn length, 10 µm; maximum process length, 5 µm. Range: central body length, 43(46)50 µm; central body width, 35(38)40 µm; average length of apical horn, 6(8)10 µm; average length of process, 2–8 µm; average height of septa, 2–5 µm (10 specimens measured).
Remarks. Spiniferella cornuta subsp. kacira subsp. nov. differs from Spiniferella cornuta subsp. cornuta Gerlach, 1961 by its shorter apical horn and processes, and by the presence of sutural processes. The new subspecies resembles Spiniferites sp. A of Kirsch (1991, p. 65, pl. 24, figs 9, 11) by its short apical horn and granular wall, but differs by its shorter processes and the presence of sutural processes. Hystrichosphaera cf. cornuta described by Davey & Williams (1966, p. 45) may be similar to the new subspecies, since it possesses a weakly granular wall, a short apical horn and sutural processes. Spiniferites seghiris (Below, 1982) Lentin & Williams, 1993 and Spiniferites twistringiensis (Maier, 1959) Fensome et al. 1990 possess numerous very short gonal and sutural processes but generally lack an apical horn.
Stratigraphic occurrence. Samples OH 2–18, planktic foraminiferal Abathomphalus mayaroensis Zone (upper Maastrichtian), Guembelitria cretacea and Parvularugoglobigerina eugubina zones (lower Danian), Ouled Haddou section.
Holotype: Slimani et al., 2012, fig.4M–O.
Age: early Danian.
Original description (Slimani et al., 2012):
Spiniferella cornuta subsp. kasira subsp. nov. (Fig. 4K–T)
2010 Spiniferella sp. cf. Spiniferites sp. A of Kirsch (1991); Slimani et al. p. 99, pl. 2, fig. 2.
Holotype. Sample OH 12, slide 2, England Finder E46 (Fig. 4M–O).
Type locality and bed. Ouled Haddou section, north of Taza, northern Morocco; clayey marl 35 cm above the K/T boundary, lower Danian.
Etymology. From ‘kasir’ (Arabic): short, with reference to the very short processes and the apical horn.
Diagnosis. A species of Spiniferella with a granular surface, short processes and a distinct apical horn. Operculum mostly free.
Description. The proximate to proximochorate dinoflagellate cyst has an ovoid central body. The wall of the cornucavate cyst consists of a granular endophragm with a maximum thickness of 1 µm and a thin (0.5 µm) smooth to slightly granular periphragm (Fig. 4N, P, S). The periphragm forms a small but distinct apical horn. The horn is hollow, broad-based and tapers distally to a blunt or truncated distal end (Fig. 4M, P). The processes are short (maximum 5 µm long). The sutural processes are distally bifid to weakly bifurcate (Fig. 4L, N). The gonal processes are generally slightly longer than the sutural processes and are discretely bifurcate or trifurcate (Fig. 4N, R, S). The sutural septa are of low height and generally concave between processes. The observed gonyaulacoid tabulation is that of Spiniferella and is indicated by the processes, septa and archeopyle.
Dimensions:
Holotype: central body length, 43 µm; central body width, 40 µm; apical horn length, 10 µm; maximum process length, 5 µm. Range: central body length, 43(46)50 µm; central body width, 35(38)40 µm; average length of apical horn, 6(8)10 µm; average length of process, 2–8 µm; average height of septa, 2–5 µm (10 specimens measured).
Remarks. Spiniferella cornuta subsp. kacira subsp. nov. differs from Spiniferella cornuta subsp. cornuta Gerlach, 1961 by its shorter apical horn and processes, and by the presence of sutural processes. The new subspecies resembles Spiniferites sp. A of Kirsch (1991, p. 65, pl. 24, figs 9, 11) by its short apical horn and granular wall, but differs by its shorter processes and the presence of sutural processes. Hystrichosphaera cf. cornuta described by Davey & Williams (1966, p. 45) may be similar to the new subspecies, since it possesses a weakly granular wall, a short apical horn and sutural processes. Spiniferites seghiris (Below, 1982) Lentin & Williams, 1993 and Spiniferites twistringiensis (Maier, 1959) Fensome et al. 1990 possess numerous very short gonal and sutural processes but generally lack an apical horn.
Stratigraphic occurrence. Samples OH 2–18, planktic foraminiferal Abathomphalus mayaroensis Zone (upper Maastrichtian), Guembelitria cretacea and Parvularugoglobigerina eugubina zones (lower Danian), Ouled Haddou section.