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Odontochitina indigena
Odontochitina indigena Marshall, 1988
Holotype: Marshall, 1988, fig.11Q-S
Locus typicus: Gippsland Basin, SE Australia
Stratum typicum: Santonian
Original diagnosis: Marshall, 1988, p. 198
Ventrodorsal outline of central body subtriangular, apices extended to form a long slender apical, antapical, and right cingular horn each with a pointed tip. Cingular horn L-shaped, with prominent postcingular extension. Antapical horn and postcingular portion of cingular horn weakly to moderately divergent. Wall layers usually only separated around horn bases, occasionally also separated along part or all of lateral margins below archeopyle suture and along antapical margin. Endophragm c. 0.5-1.0 µm thick, surface finely reticulate: lacunae subcircular, c. 0.5-1.0 µm in diameter; muri c. 0.5 µm wide. Periphragm c. 0.5 µm thick; surface smooth on central body, smooth to scabrate on horns; extended to form numerous simple spines up to 9 µm long. Spines longest on central body, becoming smaller and sparser towards tips of horns. Spines nontabulate, intratabular or arranged in parasutural rows with their bases often interconnected by weak to distinct parasutural ridges. Intratabular spines irregularly distributed or aligned parallel to parasutural features and often also interconnected by discontinuous ridges. Paraplates defined on specimens with most pronounced parasutural features: 1-3", 6", 1-4c, 1-3""" (Fig.5). Midventral part of pericyst and horns often with longitudinal ridges lacking consistent arrangement. Periphragm with scattered perforations where wall layers separate around bases of horns. Paracingulum indicated on periphragm by 2 parallel rows of spines joined by ridges, 5-8µm apart, and separated by a shallow groove. Archeopyle apical Type (tA), accessory sutures occasionally evident between precingular paraplates. Operculum free. Dimensions. Endocyst without operculum, length 44 (60) 65 µm, width 41 (55) 64 µm; antapical horn, length 54 (74) 94 µm; postcingular portion of cingular horn, length 42(59)66µm (14 specimens); apical horn, length 56, 71 µm (2 specimens).
Holotype: Marshall, 1988, fig.11Q-S
Locus typicus: Gippsland Basin, SE Australia
Stratum typicum: Santonian
Original diagnosis: Marshall, 1988, p. 198
Ventrodorsal outline of central body subtriangular, apices extended to form a long slender apical, antapical, and right cingular horn each with a pointed tip. Cingular horn L-shaped, with prominent postcingular extension. Antapical horn and postcingular portion of cingular horn weakly to moderately divergent. Wall layers usually only separated around horn bases, occasionally also separated along part or all of lateral margins below archeopyle suture and along antapical margin. Endophragm c. 0.5-1.0 µm thick, surface finely reticulate: lacunae subcircular, c. 0.5-1.0 µm in diameter; muri c. 0.5 µm wide. Periphragm c. 0.5 µm thick; surface smooth on central body, smooth to scabrate on horns; extended to form numerous simple spines up to 9 µm long. Spines longest on central body, becoming smaller and sparser towards tips of horns. Spines nontabulate, intratabular or arranged in parasutural rows with their bases often interconnected by weak to distinct parasutural ridges. Intratabular spines irregularly distributed or aligned parallel to parasutural features and often also interconnected by discontinuous ridges. Paraplates defined on specimens with most pronounced parasutural features: 1-3", 6", 1-4c, 1-3""" (Fig.5). Midventral part of pericyst and horns often with longitudinal ridges lacking consistent arrangement. Periphragm with scattered perforations where wall layers separate around bases of horns. Paracingulum indicated on periphragm by 2 parallel rows of spines joined by ridges, 5-8µm apart, and separated by a shallow groove. Archeopyle apical Type (tA), accessory sutures occasionally evident between precingular paraplates. Operculum free. Dimensions. Endocyst without operculum, length 44 (60) 65 µm, width 41 (55) 64 µm; antapical horn, length 54 (74) 94 µm; postcingular portion of cingular horn, length 42(59)66µm (14 specimens); apical horn, length 56, 71 µm (2 specimens).