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Membranilarnacia hapala
Membranilarnacia hapala (Schiøler and Wilson, 1993, p.346-347, pl.2, figs.1-7; text-figs.12a-b) Lachkar and Masure in Fauconnier and Masure, 2004, p.387.
Originally Eatonicysta, subsequently (and now) Membranilarnacia.
This name (not as a new combination, formal or proposed, attributed to an unpublished thesis) was not validly published in Slimani (2001a, p.192).
Holotype: Schiøler and Wilson, 1993, pl.2, fig.6.
Age: Late Campanian-Early Maastrichtian.
Original diagnosis: Schioler and Wilson, 1993, p. 346
An Eatonicysta possessing a thin entire spherical ectophragm, connecting the process tips. The periphragm is verrucate between the processes. The larger paraplates typically possess intratabular process complexes.
Description: The cyst body is spherical, giving rise to processes that are connected distally by a thin and finely reticulate spherical ectophragm. Two types of processes are present on the larger paraplates of one specimen; large hollow and trumpate intratabular processes, one per paraplate, and more slender solid and tapering processes that either are closely arranged in process complexes in the central part of the paraplates, or occurlsingly in intratabular position on smaller paraplates. The larger paraplates predominantly have process complexes, whereas the sulcal paraplates only have single processes. The cyst body is ornamented with verrucae (0.5-1.5 Ám in diameter). Each verruca encloses a small coel, representing a vacuole enclosed between the endo- and periphragm. Refraction in the small coel gives the verruca a ring-shaped appearance when viewed slightly out of focus at high magnification (Plate II, 4). The larger paraplates are indicated by intratabular processes or process complexes, the paracingulum is not indicated. The sulcal plates are indicated by a few small solid processes. In Kofoid notation the observed paratabulation is ?", 6"", 0c , 5-6s, 6""", 1p, 1"""", the Taylor-Evitt paratabulation is denoted in Fig. 12. The archaeopyle is apical (A) with a prominent sulcal notch; the operculum is free.
Stratigraphic occurrence: Middle part of the Early Maastrichtian (basal occidentalis Zone), and possibly older strata in the Dan field. Late Campanian to earliest Maastrichtian (langei Zone to lanceolata Zone) onshore Denmark.
Dimensions (12 specimens measured, only loisthocysts measured)
Holotype --- range
Total length 63 µm --- 56 (63) 79 µm
Total width 68 µm --- 62 (67) 79 µm
Length of endocyst 37 µm --- 37 (44) 47 µm
Width of endocyst 40 µm --- 40 (47) 53 µm
Affinities:Schioler and Wilson, 1993, p. 346, 347
The species differs from other species of Eatonicysta in having intratabular process complexes on some of the larger paraplates. Although this is an important difference, we do not consider it sufficient reason to create a new genus. Besides the presence of process complexes, Eatonicysta hapala sp. nov. differs from Eatonicysta pterococcoides (O. Wetzel, 1933) Sarjeant, 1985, and Eatonicysta ursulae (Morgenroth, 1966) Stover and Evitt, 1978, in having a verrucate endophragm. It is further distinguished from the latter species in having an entire ectophragm. The specimens from the Danish North Sea have been compared to Wilson"s specimen H1-40, which was designated as the holotype of "Membranilarnacia hapala" by Wilson, 1974, and the identity has been confirmed.
Originally Eatonicysta, subsequently (and now) Membranilarnacia.
This name (not as a new combination, formal or proposed, attributed to an unpublished thesis) was not validly published in Slimani (2001a, p.192).
Holotype: Schiøler and Wilson, 1993, pl.2, fig.6.
Age: Late Campanian-Early Maastrichtian.
Original diagnosis: Schioler and Wilson, 1993, p. 346
An Eatonicysta possessing a thin entire spherical ectophragm, connecting the process tips. The periphragm is verrucate between the processes. The larger paraplates typically possess intratabular process complexes.
Description: The cyst body is spherical, giving rise to processes that are connected distally by a thin and finely reticulate spherical ectophragm. Two types of processes are present on the larger paraplates of one specimen; large hollow and trumpate intratabular processes, one per paraplate, and more slender solid and tapering processes that either are closely arranged in process complexes in the central part of the paraplates, or occurlsingly in intratabular position on smaller paraplates. The larger paraplates predominantly have process complexes, whereas the sulcal paraplates only have single processes. The cyst body is ornamented with verrucae (0.5-1.5 Ám in diameter). Each verruca encloses a small coel, representing a vacuole enclosed between the endo- and periphragm. Refraction in the small coel gives the verruca a ring-shaped appearance when viewed slightly out of focus at high magnification (Plate II, 4). The larger paraplates are indicated by intratabular processes or process complexes, the paracingulum is not indicated. The sulcal plates are indicated by a few small solid processes. In Kofoid notation the observed paratabulation is ?", 6"", 0c , 5-6s, 6""", 1p, 1"""", the Taylor-Evitt paratabulation is denoted in Fig. 12. The archaeopyle is apical (A) with a prominent sulcal notch; the operculum is free.
Stratigraphic occurrence: Middle part of the Early Maastrichtian (basal occidentalis Zone), and possibly older strata in the Dan field. Late Campanian to earliest Maastrichtian (langei Zone to lanceolata Zone) onshore Denmark.
Dimensions (12 specimens measured, only loisthocysts measured)
Holotype --- range
Total length 63 µm --- 56 (63) 79 µm
Total width 68 µm --- 62 (67) 79 µm
Length of endocyst 37 µm --- 37 (44) 47 µm
Width of endocyst 40 µm --- 40 (47) 53 µm
Affinities:Schioler and Wilson, 1993, p. 346, 347
The species differs from other species of Eatonicysta in having intratabular process complexes on some of the larger paraplates. Although this is an important difference, we do not consider it sufficient reason to create a new genus. Besides the presence of process complexes, Eatonicysta hapala sp. nov. differs from Eatonicysta pterococcoides (O. Wetzel, 1933) Sarjeant, 1985, and Eatonicysta ursulae (Morgenroth, 1966) Stover and Evitt, 1978, in having a verrucate endophragm. It is further distinguished from the latter species in having an entire ectophragm. The specimens from the Danish North Sea have been compared to Wilson"s specimen H1-40, which was designated as the holotype of "Membranilarnacia hapala" by Wilson, 1974, and the identity has been confirmed.