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Walvisia woodii
Walvisia woodii Miles, 1990
Holotype: Miles, 1990, pl.2, figs.1-3
Locus typicus: Offshore Namibia, S Atlantic
Stratum typicum: Late Albian
Original diagnosis: Miles, 1990, p. 84
Chorate dinoflagellate cyst with an ovoidal to subspheroidal main body and a short, bluntly rounded apical horn. The cyst wall is two-layered, consisting of a smooth endophragm and a strongly fibro-reticulate periphragm. The processes vary in degree of complexity, but are of roughly uniform length. Processes are composed of fibrous elements which arise from, and are continuous with, the fibro-reticulate periphragm. The simplest processes are confined to the cingular and sulcal regions. These are proximally fibrous, with the fibers coalescing distally to form a solid tip which may be blunt or acuminate. Processes outside the cingular and sulcal zones are more complex, with wider bases and distal furcations. Processes are composed of numerous fibrous elements that are intricately inter-linked throughout their length. The process formula reflects the typical gonyaulacoid tabulation characteristic of the genus Walvisia. With the exception of the cingular series, the processes are plate-centered; the cingular plates are represented by pairs of simple processes. A two-plate precingular archeopyle is formed by the loss of paraplates 2" and 3". Operculum not observed.
Dimensions. Minimum (average) maximum: length (excluding horn) 33(36)39 µm, width 29(31)35 µm, process length 10(13)14 µm, apical horn length 3(3)4 µm.
Holotype: Miles, 1990, pl.2, figs.1-3
Locus typicus: Offshore Namibia, S Atlantic
Stratum typicum: Late Albian
Original diagnosis: Miles, 1990, p. 84
Chorate dinoflagellate cyst with an ovoidal to subspheroidal main body and a short, bluntly rounded apical horn. The cyst wall is two-layered, consisting of a smooth endophragm and a strongly fibro-reticulate periphragm. The processes vary in degree of complexity, but are of roughly uniform length. Processes are composed of fibrous elements which arise from, and are continuous with, the fibro-reticulate periphragm. The simplest processes are confined to the cingular and sulcal regions. These are proximally fibrous, with the fibers coalescing distally to form a solid tip which may be blunt or acuminate. Processes outside the cingular and sulcal zones are more complex, with wider bases and distal furcations. Processes are composed of numerous fibrous elements that are intricately inter-linked throughout their length. The process formula reflects the typical gonyaulacoid tabulation characteristic of the genus Walvisia. With the exception of the cingular series, the processes are plate-centered; the cingular plates are represented by pairs of simple processes. A two-plate precingular archeopyle is formed by the loss of paraplates 2" and 3". Operculum not observed.
Dimensions. Minimum (average) maximum: length (excluding horn) 33(36)39 µm, width 29(31)35 µm, process length 10(13)14 µm, apical horn length 3(3)4 µm.