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Kenleyia shabaka
Kenleyia shabaka Slimani et al., 2012. p.345–346, fig.5A–L.
Holotype: Slimani et al., 2012, fig.5A–D.
Age: early Danian.
Original description (Slimani et al., 2012):
Kenleyia shabaka sp. nov. (Fig. 5A–L)
2010 Kenleyia? sp. A; Slimani et al., p. 101, pl. 3, figs 7, 8.
Holotype. Sample OH 14, slide 1, England Finder F35 (Fig. 5A–D).
Type locality and bed. Ouled Haddou section, north of Taza, northern Morocco; marl 50 cm above the K/ T boundary, lower Danian.
Etymology. From ‘shabaka’ (Arabic): net-like, with reference to the surface ornamentation of the cyst.
Diagnosis. A medium-sized ovoid to subspherical Kenleyia species with a reticulate wall bearing nontabular, short and tiny projections and processes. The precingular archeopyle is formed by the loss of a single plate and is the sole indication of tabulation.
Description. The proximate dinoflagellate cyst has an ovoid to subspherical shape and is characterized by an apical and an antapical horn-like projection (Fig. 5F). The acavate wall is relatively thick (maximum 1 µm) and consists of a smooth endophragm, and a closely appressed slightly granular and coarsely reticulate periphragm. Lumina are irregular in shape and their maximum size varies considerably (2–12 µm). The imperfect reticulum covers the entire cyst and gives rise to nontabular, tiny and slender projections and processes (1–5 µm long; Fig. 5H, J), which have acuminate to rarely bifid distal ends. In some cases the cingulum is expressed by low ridges (Fig. 5K, L). The archeopyle is precingular (type P) and is formed by loss of plate 3’’ (Fig. 5A, F, H, K). The operculum is free or sporadically in place.
Dimensions. Holotype: overall length, 70 µm; width, 56 µm; length of apical horn, 5 µm; length of antapical horn, 4 µm. Range: overall length, 60(67)71 µm; width, 50(56)60 µm; length of apical horn, 4–8 µm; length of antapical horn, 3–7 µm (10 specimens measured).
Remarks. The reticulate periphragm with the tiny and slender projections and processes, plus the absence of an external fibrous layer renders Kenleyia chabaka sp. nov. distinct from all other Kenleya species. The new species differs from Kenleyia sp. A of Oboh-Ikuenobe et al. (1998, pl. 7, figs 1–3) by its larger reticulum and the absence of an external layer. Carpatella septata Willumsen, 2004 differs from the new species in having a distinct tabulation expressed by complexes of penitabular septa.
Stratigraphic occurrence. Samples OH 5–19, planktic foraminiferal Abathomphalus mayaroensis Zone (upper Maastrichtian), Guembelitria cretacea and Parvularugoglobigerina eugubina zones (lower Danian), Ouled Haddou section.
Holotype: Slimani et al., 2012, fig.5A–D.
Age: early Danian.
Original description (Slimani et al., 2012):
Kenleyia shabaka sp. nov. (Fig. 5A–L)
2010 Kenleyia? sp. A; Slimani et al., p. 101, pl. 3, figs 7, 8.
Holotype. Sample OH 14, slide 1, England Finder F35 (Fig. 5A–D).
Type locality and bed. Ouled Haddou section, north of Taza, northern Morocco; marl 50 cm above the K/ T boundary, lower Danian.
Etymology. From ‘shabaka’ (Arabic): net-like, with reference to the surface ornamentation of the cyst.
Diagnosis. A medium-sized ovoid to subspherical Kenleyia species with a reticulate wall bearing nontabular, short and tiny projections and processes. The precingular archeopyle is formed by the loss of a single plate and is the sole indication of tabulation.
Description. The proximate dinoflagellate cyst has an ovoid to subspherical shape and is characterized by an apical and an antapical horn-like projection (Fig. 5F). The acavate wall is relatively thick (maximum 1 µm) and consists of a smooth endophragm, and a closely appressed slightly granular and coarsely reticulate periphragm. Lumina are irregular in shape and their maximum size varies considerably (2–12 µm). The imperfect reticulum covers the entire cyst and gives rise to nontabular, tiny and slender projections and processes (1–5 µm long; Fig. 5H, J), which have acuminate to rarely bifid distal ends. In some cases the cingulum is expressed by low ridges (Fig. 5K, L). The archeopyle is precingular (type P) and is formed by loss of plate 3’’ (Fig. 5A, F, H, K). The operculum is free or sporadically in place.
Dimensions. Holotype: overall length, 70 µm; width, 56 µm; length of apical horn, 5 µm; length of antapical horn, 4 µm. Range: overall length, 60(67)71 µm; width, 50(56)60 µm; length of apical horn, 4–8 µm; length of antapical horn, 3–7 µm (10 specimens measured).
Remarks. The reticulate periphragm with the tiny and slender projections and processes, plus the absence of an external fibrous layer renders Kenleyia chabaka sp. nov. distinct from all other Kenleya species. The new species differs from Kenleyia sp. A of Oboh-Ikuenobe et al. (1998, pl. 7, figs 1–3) by its larger reticulum and the absence of an external layer. Carpatella septata Willumsen, 2004 differs from the new species in having a distinct tabulation expressed by complexes of penitabular septa.
Stratigraphic occurrence. Samples OH 5–19, planktic foraminiferal Abathomphalus mayaroensis Zone (upper Maastrichtian), Guembelitria cretacea and Parvularugoglobigerina eugubina zones (lower Danian), Ouled Haddou section.