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Deflandrea phosphoritica ssp. phosphoritica
Deflandrea phosphoritica ssp. phosphoritica
Autonym
Holotype: Eisenack, 1938, text-fig.6
Locus typicus: Samland, Russia
Stratum typicum: Late Eocene-Early Oligocene
Translation Eisenack, 1938: LPP
Translation Gocht, 1969: Geological Survey of Canada
Original description: Eisenack 1938, p. 187
Diagnosis: Body slightly flattened; in outline an elongated bilateral symmetrical pentagon, with a convex antapical side. Thus an apical and two nearly equal antapical horns are formed; two lateral horns are obtuse-angled and indented at the top. The shell is transparent, without tabulation; ventrally with wide, slightly deepened lateral- (girdle-) fold, which is equivalent to the lateral furrow, just beneath the equator. Dorsally a flagellar pore is present between the antapical horns. A rounded inner capsule, without an apical cover, is present.
Gocht, 1969, p.10:
Deflandrea phosphoritica is a well known species which has already been described many times. In Meckelfeld, it begins only in the upper part of Early Eocene 3, and extends to the Middle Oligocene. It is never frequent. Probably all of the specimens belong to the nominate subspecies.
The body outline varies within known limits; we find both the typical formation with blunt horns and widely projecting hypotheca, and slimmer individuals with acute horns and concave antapex. Usually also the longitudinal furrow is visible, extending from the cingulum down to the antapex (cf. Manum, 1960; Rozen, 1965 and Eisenack, 1966). The transverse furrow is a shallow, slightly indented band on the dorsal side, becoming somewhat deeper toward the flanks. The external membrane is smooth to weakly punctate; in one variant in sample 47, it was covered with small, dome-shaped verrucae. Between the antapical horns, one can sometimes see the openings which Eisenack interpreted as flagellar slits. Some specimens show traces of tabulation on the dorsal side: Below the intercalary
archeopyle, symmetrical cracks spread left and right, bounding the middle preequatoral plate 3"". Finely fimbriate surface sculpture running parallel to these cracks removes all doubt (in this connection, cf. Eisenack, 1966). The inner body is thicker than the outer armor and usually smooth or finely punctate. However, it may also exhibit large verrucae, which, as described my Manum, 1960, run around the body meridionally, leaving central areas without warts on the dorsal and ventral
side. The boundaries of these wartless areas (the dorsal area is large, the ventral smaller) confirm Manum"s observations. Occasionally, individual verrucae extend onto the dorsal surface at the level of the cingular boundaries. In exceptional cases, the archeopyle calotte may still be present in situ (3 specimens).
Occurrence: Early Eocene- Middle Oligocene.
Autonym
Holotype: Eisenack, 1938, text-fig.6
Locus typicus: Samland, Russia
Stratum typicum: Late Eocene-Early Oligocene
Translation Eisenack, 1938: LPP
Translation Gocht, 1969: Geological Survey of Canada
Original description: Eisenack 1938, p. 187
Diagnosis: Body slightly flattened; in outline an elongated bilateral symmetrical pentagon, with a convex antapical side. Thus an apical and two nearly equal antapical horns are formed; two lateral horns are obtuse-angled and indented at the top. The shell is transparent, without tabulation; ventrally with wide, slightly deepened lateral- (girdle-) fold, which is equivalent to the lateral furrow, just beneath the equator. Dorsally a flagellar pore is present between the antapical horns. A rounded inner capsule, without an apical cover, is present.
Gocht, 1969, p.10:
Deflandrea phosphoritica is a well known species which has already been described many times. In Meckelfeld, it begins only in the upper part of Early Eocene 3, and extends to the Middle Oligocene. It is never frequent. Probably all of the specimens belong to the nominate subspecies.
The body outline varies within known limits; we find both the typical formation with blunt horns and widely projecting hypotheca, and slimmer individuals with acute horns and concave antapex. Usually also the longitudinal furrow is visible, extending from the cingulum down to the antapex (cf. Manum, 1960; Rozen, 1965 and Eisenack, 1966). The transverse furrow is a shallow, slightly indented band on the dorsal side, becoming somewhat deeper toward the flanks. The external membrane is smooth to weakly punctate; in one variant in sample 47, it was covered with small, dome-shaped verrucae. Between the antapical horns, one can sometimes see the openings which Eisenack interpreted as flagellar slits. Some specimens show traces of tabulation on the dorsal side: Below the intercalary
archeopyle, symmetrical cracks spread left and right, bounding the middle preequatoral plate 3"". Finely fimbriate surface sculpture running parallel to these cracks removes all doubt (in this connection, cf. Eisenack, 1966). The inner body is thicker than the outer armor and usually smooth or finely punctate. However, it may also exhibit large verrucae, which, as described my Manum, 1960, run around the body meridionally, leaving central areas without warts on the dorsal and ventral
side. The boundaries of these wartless areas (the dorsal area is large, the ventral smaller) confirm Manum"s observations. Occasionally, individual verrucae extend onto the dorsal surface at the level of the cingular boundaries. In exceptional cases, the archeopyle calotte may still be present in situ (3 specimens).
Occurrence: Early Eocene- Middle Oligocene.