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Wetzeliella lunaris
From Fensome et al., 2019:
Wetzeliella lunaris Gocht, 1969
NOW Axiodinium. Originally Wetzeliella, subsequently (and now) Axiodinium.
Holotype: Gocht, 1969, pl.10, fig.3
Age: Early Eocene
Locus Typicus: Meckelfeld core 86
Stratum Typicum: Early Eocene
Translation Gocht, 1969: Geological Survey of Canada
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Diagnosis Gocht, 1969, p.14:
Body pentangular to rhomboid, flat. Lateral margin only slightly notched. Apical horn, lateral horns, and sinistral antapical horn well developed. Processes numerous, medium-length. Inner body thin-walled. Towards the apex, the (larger) outer archeopyle is constricted in a semicircle by the inner body membrane.
Description Gocht, 1969, p.14-15:
The external armor has a roughly pentangular outline and is thin-walled and flat. Apical horn and lateral horns are well developed, as is the sinistral antapical horn, whereas the dextral antapical horn is always more reduced. The lateral margin of the armor is fairly straight between the polar and lateral horns, so that the shape of the body is hardly affected by the widened bases of the processes.
The inner body is thin-walled and weakly granulate. The processes are only of medium length, and rather stiff; they usually become smaller towards the horns. The appendages are slightly widened proximally and also distally, where they may also be singly furcate.
"Mapping" the bases of processes does not reveal any regular pattern on the main body. However, frequently a double row of processes marks a dorsal "cingular zone" which sometimes extends onto the lateral horns. Otherwise, no connection appears between the distribution of spines and the sutures of a tabulation. A few counts gave numbers of processes between 161 and 227.
The archeopyle is characterized by the distinct incongruence of the outer and inner openings. The capsule archeopyle is always smaller, although the difference appears only at the apical end, whereas the boundaries on the cingular side coincide or at least are closely juxtaposed. The semilunar shape of the inner body membrane on the upper edge of the pylome is a characteristic feature, even though it is not limited exclusively to W. lunaris. When opercula are present inside the armor, they always show the size and shape of the outer lid, although sometimes the boundary line of the capsular lid can be seen on them. Therefore, the two opercula adhere to each other in situ. Since outer and inner body form separate pylome margins at least towards the pole, they might not have been fused there. At best, we might assume that they adhered to each other in the region near the cingulum, and this would explain why the two lids remain attached to each other even after ejection-- as is evidenced in the case of certain other Wetzeliella species (W. solida, W. draco) by the fact that the capsule lies free inside. The flagellar insertions are quite small, slit-shaped, branched or unbranched, and frequently distinctly inclined toward the dextral antapical horn.
Measurements: Holotype: length: breadth = 148: 155 µm, inner body 86: 85 µm. Other specimens: length 144-161 µm, breadth 144-159 µm, inner body diameter 78-92 µm. Length of processes 2-11 µm (usually ca.6 µm).
Affinities: W. lunaris is differentiated from W. articulata by the shape of the archeopyle, generally greater asymmetry, and by the lateral margins, which are often straight between the horns. W. meckelfeldensis has more distinctly notched lateral margins compared to W. lunaris, and longer processes.
Wetzeliella lunaris Gocht, 1969
NOW Axiodinium. Originally Wetzeliella, subsequently (and now) Axiodinium.
Holotype: Gocht, 1969, pl.10, fig.3
Age: Early Eocene
Locus Typicus: Meckelfeld core 86
Stratum Typicum: Early Eocene
Translation Gocht, 1969: Geological Survey of Canada
---------------------------------------------------------------------------------------------------
Diagnosis Gocht, 1969, p.14:
Body pentangular to rhomboid, flat. Lateral margin only slightly notched. Apical horn, lateral horns, and sinistral antapical horn well developed. Processes numerous, medium-length. Inner body thin-walled. Towards the apex, the (larger) outer archeopyle is constricted in a semicircle by the inner body membrane.
Description Gocht, 1969, p.14-15:
The external armor has a roughly pentangular outline and is thin-walled and flat. Apical horn and lateral horns are well developed, as is the sinistral antapical horn, whereas the dextral antapical horn is always more reduced. The lateral margin of the armor is fairly straight between the polar and lateral horns, so that the shape of the body is hardly affected by the widened bases of the processes.
The inner body is thin-walled and weakly granulate. The processes are only of medium length, and rather stiff; they usually become smaller towards the horns. The appendages are slightly widened proximally and also distally, where they may also be singly furcate.
"Mapping" the bases of processes does not reveal any regular pattern on the main body. However, frequently a double row of processes marks a dorsal "cingular zone" which sometimes extends onto the lateral horns. Otherwise, no connection appears between the distribution of spines and the sutures of a tabulation. A few counts gave numbers of processes between 161 and 227.
The archeopyle is characterized by the distinct incongruence of the outer and inner openings. The capsule archeopyle is always smaller, although the difference appears only at the apical end, whereas the boundaries on the cingular side coincide or at least are closely juxtaposed. The semilunar shape of the inner body membrane on the upper edge of the pylome is a characteristic feature, even though it is not limited exclusively to W. lunaris. When opercula are present inside the armor, they always show the size and shape of the outer lid, although sometimes the boundary line of the capsular lid can be seen on them. Therefore, the two opercula adhere to each other in situ. Since outer and inner body form separate pylome margins at least towards the pole, they might not have been fused there. At best, we might assume that they adhered to each other in the region near the cingulum, and this would explain why the two lids remain attached to each other even after ejection-- as is evidenced in the case of certain other Wetzeliella species (W. solida, W. draco) by the fact that the capsule lies free inside. The flagellar insertions are quite small, slit-shaped, branched or unbranched, and frequently distinctly inclined toward the dextral antapical horn.
Measurements: Holotype: length: breadth = 148: 155 µm, inner body 86: 85 µm. Other specimens: length 144-161 µm, breadth 144-159 µm, inner body diameter 78-92 µm. Length of processes 2-11 µm (usually ca.6 µm).
Affinities: W. lunaris is differentiated from W. articulata by the shape of the archeopyle, generally greater asymmetry, and by the lateral margins, which are often straight between the horns. W. meckelfeldensis has more distinctly notched lateral margins compared to W. lunaris, and longer processes.