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Danea chibanis
Danea chibanis Below, 1981
Originally (and now) Danea, subsequently Damassadinium (generic name illegitimate).
Holotype: Below, 1981, pl.6, figs.4a-c; Fensome et al., 1991, figs.1-3 - p.613
Paratype: Below, 1981, pl.6, figs.3a-b
Locus typicus: Ravine northwest of Amalou, southwest Morocco
Stratum typicum: Aptian: Gargasian
Translation Below, 1981: Fensome, 1991, p. 514-617
Original diagnosis: Below, 1981, p. 44
Proximate tabulate cyst. Body oval or elongate-oval, rarely elongate pentagonal. Endophragm and periphragm smooth. The spiral paracingulum divides the cyst unequally into an epicyst with a triangular apical horn and a somewhat smaller hypocyst. Strong, penitabular, bulgelike ribs mark the position of the paraplates which are arranged according to the scheme 4", 6", 6c, 6n", pc, 1"""", as, ra, rs, ls, ps. Apical and paracingular paraplates, as well as l""", pc and the parasulcals are reflected by intratabular ribs or knots, whereas the remaining paraplates have penitabular ridges. The archeopyle is of type P(3"").
Original description: Below, 1981, p. 44
Elongate-oval specimens with severely flattened poles and oval specimens with an epicyst that is triangular in outline predominate, in contrast to cysts with a pentagonal or rhombic outline, [the shape being] influenced by the degree of rounding of the antapex.
The strong endophragm forms a conical apical horn, whose length equals its basal diameter. It is either set-off or, if triangular, is included in the outline of the epicyst.
Intratabular knots and ribs and low penitabular ribs are formed by the unstructured periphragm. The septa are distally thickened in a bulge-like manner. In many instances they are also proximally reinforced, so that solid, broad ribs extend from the cyst. Distally, these are irregularly undulate or lacerated. Commonly, the septa partially break down to form short costae or rows of knots. The costae are rarely broken down completely and the paratabulation can be reconstructed as follows ([Below, 1981a] text-fig.33).
The four apical paraplates are represented by intratabular costae. 1" and 4" are long and extend anteriorly from 6n and as [anterior sulcal] to the apex. Occasionally, they are reduced and form two knots. In contrast, 2" and 3" are tangential to the pole and anterior to 2" and 4". The left margin of 2" and the right margin of 3" commonly curve and extend towards the apex ([Below, 1981a] text-fig.35). Occasionally, the tangential parts are reduced so that only the radial costae indicate the position of these paraplates. Occasionally, indications of 2" and 3" are absent. Posterior to these are 6 precingular paraplates. Whereas the equal-sized triangular to trapezoidal fields of 1" to 5" are enclosed by penitabular bulges, 6n is marked by a short, straight costa; in some examples the anterior and posterior ends of this costa may be arched towards the parasulcus. Exceptionally, 6n is bordered by the parasulcus. The paracingulum comprises a series of six commonly isolated intratabular costae. A knot, which is located at the right end of the paracingulum, but commonly somewhat posteriorly displaced, is interpreted as a relict of paraplate ra. Six postcingular paraplates occur posterior to the paracingulum. The positions of 2n" to 6"n are indicated by penitabular septa. 2"n and 6"n are small, triangular in outline, and equal in size. 6"n is commonly open towards the parasulcus or only delimited by a row of knots. 3""", 4""" and 5""" are large and trapezoidal to almost square. One, often somewhat elongate tubercle occurs in an almost constant position adjacent to 2""" and 6""". In my opinion these tubercles should be interpreted as homologous to plates 1""" and rs. Similarly, I interpret a longish costa between 2""" and 1"""" as pc and that a variable number of costae or knots that delimit the parasulcus posteriorly may reflect pc. Low bulges may occur in the centre of the hypocystal parasulcus and indicate ls, whereas as [anterior sulcal], in the epicystal part of the parasulcus, is usually represented by a distinct, elongate costa parallel to the longitudinal axis of the cyst, or more rarely by a penitabular septum. 1"""" is a square, but usually rounded area and is surrounded by very high septa. If they fuse distally above 1"""", they form a hollow antapical hom.
The archeopyle is pentagonal. The operculum corresponds to the third precingular paraplate; thus, the archeopyle is of type P(3"").
Originally (and now) Danea, subsequently Damassadinium (generic name illegitimate).
Holotype: Below, 1981, pl.6, figs.4a-c; Fensome et al., 1991, figs.1-3 - p.613
Paratype: Below, 1981, pl.6, figs.3a-b
Locus typicus: Ravine northwest of Amalou, southwest Morocco
Stratum typicum: Aptian: Gargasian
Translation Below, 1981: Fensome, 1991, p. 514-617
Original diagnosis: Below, 1981, p. 44
Proximate tabulate cyst. Body oval or elongate-oval, rarely elongate pentagonal. Endophragm and periphragm smooth. The spiral paracingulum divides the cyst unequally into an epicyst with a triangular apical horn and a somewhat smaller hypocyst. Strong, penitabular, bulgelike ribs mark the position of the paraplates which are arranged according to the scheme 4", 6", 6c, 6n", pc, 1"""", as, ra, rs, ls, ps. Apical and paracingular paraplates, as well as l""", pc and the parasulcals are reflected by intratabular ribs or knots, whereas the remaining paraplates have penitabular ridges. The archeopyle is of type P(3"").
Original description: Below, 1981, p. 44
Elongate-oval specimens with severely flattened poles and oval specimens with an epicyst that is triangular in outline predominate, in contrast to cysts with a pentagonal or rhombic outline, [the shape being] influenced by the degree of rounding of the antapex.
The strong endophragm forms a conical apical horn, whose length equals its basal diameter. It is either set-off or, if triangular, is included in the outline of the epicyst.
Intratabular knots and ribs and low penitabular ribs are formed by the unstructured periphragm. The septa are distally thickened in a bulge-like manner. In many instances they are also proximally reinforced, so that solid, broad ribs extend from the cyst. Distally, these are irregularly undulate or lacerated. Commonly, the septa partially break down to form short costae or rows of knots. The costae are rarely broken down completely and the paratabulation can be reconstructed as follows ([Below, 1981a] text-fig.33).
The four apical paraplates are represented by intratabular costae. 1" and 4" are long and extend anteriorly from 6n and as [anterior sulcal] to the apex. Occasionally, they are reduced and form two knots. In contrast, 2" and 3" are tangential to the pole and anterior to 2" and 4". The left margin of 2" and the right margin of 3" commonly curve and extend towards the apex ([Below, 1981a] text-fig.35). Occasionally, the tangential parts are reduced so that only the radial costae indicate the position of these paraplates. Occasionally, indications of 2" and 3" are absent. Posterior to these are 6 precingular paraplates. Whereas the equal-sized triangular to trapezoidal fields of 1" to 5" are enclosed by penitabular bulges, 6n is marked by a short, straight costa; in some examples the anterior and posterior ends of this costa may be arched towards the parasulcus. Exceptionally, 6n is bordered by the parasulcus. The paracingulum comprises a series of six commonly isolated intratabular costae. A knot, which is located at the right end of the paracingulum, but commonly somewhat posteriorly displaced, is interpreted as a relict of paraplate ra. Six postcingular paraplates occur posterior to the paracingulum. The positions of 2n" to 6"n are indicated by penitabular septa. 2"n and 6"n are small, triangular in outline, and equal in size. 6"n is commonly open towards the parasulcus or only delimited by a row of knots. 3""", 4""" and 5""" are large and trapezoidal to almost square. One, often somewhat elongate tubercle occurs in an almost constant position adjacent to 2""" and 6""". In my opinion these tubercles should be interpreted as homologous to plates 1""" and rs. Similarly, I interpret a longish costa between 2""" and 1"""" as pc and that a variable number of costae or knots that delimit the parasulcus posteriorly may reflect pc. Low bulges may occur in the centre of the hypocystal parasulcus and indicate ls, whereas as [anterior sulcal], in the epicystal part of the parasulcus, is usually represented by a distinct, elongate costa parallel to the longitudinal axis of the cyst, or more rarely by a penitabular septum. 1"""" is a square, but usually rounded area and is surrounded by very high septa. If they fuse distally above 1"""", they form a hollow antapical hom.
The archeopyle is pentagonal. The operculum corresponds to the third precingular paraplate; thus, the archeopyle is of type P(3"").