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Danea manicata
Danea manicata Damassa, 1984
Originally (and now) Danea, subsequently Damassadinium (generic name illegitimate).
Holotype: Damassa, 1984, pl.2, figs.1-3
Locus typicus: N California, USA
Stratum typicum: Early Eocene
Original diagnosis: Damassa, 1984, p. 55
Proximochorate cyst, ovoidal to ellipsoidal in shape; wall composed of autophragm only. Surface of wall fibrous in appearance, becomming less so toward extremities of septa and processes. Slight protrusion may be developed at apex and antapex. Gonyaulacacean paratabulation indicated by penitabular and intratabular septa of high elevation. Apical paraplates characterised by complete penitabular septa which may grade into intratabular processes; discontinuous intratabular septa and processes delineate cingular and sulcal paraplates, respectively. Large precingular (1""-5"") and postcingular (3"""-6""") paraplates posess incomplete penitabular septa: i.e., septa are undeveloped along the adcingular paraplate boundaries. Antapical septum penitabular, complete. Archeopyle Type P (3""). Description: Proximochorate cyst, ovoidal to ellipsoidal in shape, wall consisting of autophragm only.
Length of autocyst 75-83 Ám, width 54-72 Ám; holotype 75x65 Ám. Small horn may be present at apex and antapex, formed by protrusion of the wall. Wall approximately 2 Ám in thickness, fibrous in appearance. Gonyaulacacean paratabulation indicated by penitabular and intratabular septa 13-26 Ám in height. Apical paraplates characterised by penitabular septa which may grade into intratabular processes. Cingular and sulcal paraplates delineated by discontinuous rectilinear intratabular septa; posterior intercalary paraplates delineated by discrete processes. Ends of paracingulum offset a distance approximately equivalent to inferred width of cingulum. Large pre- and postcingular paraplates (1""-5"" and 3"""-6""") represented by incompletely developed penitabular septa: i.e., septa are undeveloped along adcingular margins of paraplates. Antapical paraplate delineated by completely developed penitabular septum. Paraplates adjacent to the sulcus, i.e., 6"", 1""", 2""", 1p notably smaller in size; delineated by intratabular processes. Precingular archeopyle, Type P, formed by the loss of third precingular paraplate. Archeopyle margin rounded and slightly enlarged; operculum free, not observed.
Affinities:
Damassa 1984, p. 55-56: Danea manicata closely resembles D. californica, the type species, and D. heterospinosa (Matsuoka 1983) in terms of the expression of paratabulation and of septal height relative to autocyst dimensions. D. manicata is smaller than both D. californica and D. heterospinosa in overall dimensions, and there are slight differences in wall texture between these species. Although all three may be said to have a fibrous wall texture, the surface of the cyst between processes and septa in D. californica is smoother than that of D. manicata (compare Pl. 2, figs 4-6 and Pl. 2, figs 1-3). The three species may also be distinguished by the incomplete development of penitabular septa on the large pre- and postcingular paraplates in D. manicata. This feature, although subtle in nature, is consistent among the species I have observed. D. manicata may be distinguished from D. abbreviata, D. chibanis, and D. impages by the difference in the heights of the septa relative to the dimensions of the autocyst. As for D. abbreviata, intraspecific variability occurs in terms of detail of septal development: on a few species, normally incomplete pre- and postcingular septa occasionally may be nearly complete. These apparently form a morphologic continuum in which penitabular septa may grade into intratabular processes, especially in the apical region and on the smaller pre- and postcingular paraplates.
Originally (and now) Danea, subsequently Damassadinium (generic name illegitimate).
Holotype: Damassa, 1984, pl.2, figs.1-3
Locus typicus: N California, USA
Stratum typicum: Early Eocene
Original diagnosis: Damassa, 1984, p. 55
Proximochorate cyst, ovoidal to ellipsoidal in shape; wall composed of autophragm only. Surface of wall fibrous in appearance, becomming less so toward extremities of septa and processes. Slight protrusion may be developed at apex and antapex. Gonyaulacacean paratabulation indicated by penitabular and intratabular septa of high elevation. Apical paraplates characterised by complete penitabular septa which may grade into intratabular processes; discontinuous intratabular septa and processes delineate cingular and sulcal paraplates, respectively. Large precingular (1""-5"") and postcingular (3"""-6""") paraplates posess incomplete penitabular septa: i.e., septa are undeveloped along the adcingular paraplate boundaries. Antapical septum penitabular, complete. Archeopyle Type P (3""). Description: Proximochorate cyst, ovoidal to ellipsoidal in shape, wall consisting of autophragm only.
Length of autocyst 75-83 Ám, width 54-72 Ám; holotype 75x65 Ám. Small horn may be present at apex and antapex, formed by protrusion of the wall. Wall approximately 2 Ám in thickness, fibrous in appearance. Gonyaulacacean paratabulation indicated by penitabular and intratabular septa 13-26 Ám in height. Apical paraplates characterised by penitabular septa which may grade into intratabular processes. Cingular and sulcal paraplates delineated by discontinuous rectilinear intratabular septa; posterior intercalary paraplates delineated by discrete processes. Ends of paracingulum offset a distance approximately equivalent to inferred width of cingulum. Large pre- and postcingular paraplates (1""-5"" and 3"""-6""") represented by incompletely developed penitabular septa: i.e., septa are undeveloped along adcingular margins of paraplates. Antapical paraplate delineated by completely developed penitabular septum. Paraplates adjacent to the sulcus, i.e., 6"", 1""", 2""", 1p notably smaller in size; delineated by intratabular processes. Precingular archeopyle, Type P, formed by the loss of third precingular paraplate. Archeopyle margin rounded and slightly enlarged; operculum free, not observed.
Affinities:
Damassa 1984, p. 55-56: Danea manicata closely resembles D. californica, the type species, and D. heterospinosa (Matsuoka 1983) in terms of the expression of paratabulation and of septal height relative to autocyst dimensions. D. manicata is smaller than both D. californica and D. heterospinosa in overall dimensions, and there are slight differences in wall texture between these species. Although all three may be said to have a fibrous wall texture, the surface of the cyst between processes and septa in D. californica is smoother than that of D. manicata (compare Pl. 2, figs 4-6 and Pl. 2, figs 1-3). The three species may also be distinguished by the incomplete development of penitabular septa on the large pre- and postcingular paraplates in D. manicata. This feature, although subtle in nature, is consistent among the species I have observed. D. manicata may be distinguished from D. abbreviata, D. chibanis, and D. impages by the difference in the heights of the septa relative to the dimensions of the autocyst. As for D. abbreviata, intraspecific variability occurs in terms of detail of septal development: on a few species, normally incomplete pre- and postcingular septa occasionally may be nearly complete. These apparently form a morphologic continuum in which penitabular septa may grade into intratabular processes, especially in the apical region and on the smaller pre- and postcingular paraplates.