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Leberidocysta verrucosa
Leberidocysta? verrucosa Schioler et al. 1997
Questionable assignment: Schiøler et al. (1997, p.85).
Taxonomic senior synonym: Leberidocysta? microverrucosa, according to Slimani (2001a, p.193).
Holotype: Schioler et al. 1997: GEUS Catalogue No. 1996-PS-6 (Plate III, 1-3).
Paratypes: Schioler et al. 1997: GEUS Catalogue nos 1996-PS-7 (Plate III, 4,5), 1996-PS-8 (Plate III, 6-8).
Type locality: ENCI Quarry, Maastricht, The Netherlands.
Type stratum: ENCI Quarry section 0.0 m, Lixhe 2 Member, upper Maastrichtian, Upper Cretaceous.
Diagnosis: Schioler et al. 1997, p. 85, 87
Small oval to subspherical holocavate cyst with a thin, smooth periphragm. The periphragm occasionally has folds which indicate parts of the paratabulation. The endophragm is relatively thick-walled and verrucate to vermiculate. A kidney-shaped ornament is always present ventrally on the endocyst in the sulcal area. The archeopyle is apical, type tA; the operculum is usually attached.
Description: Schioler et al. 1997, p. 87
The periphragm is thin and smooth, and is separated from the endophragm by a narrow (3-8Ám) pericoel
which usually is broadest in the antapical area (Plate III, 2, 7). The endophragm is relatively thick-walled (ca. 2 ,um) and ornamented by verrucae (diameter: 1-3Ám) or vermiculae (length: 3-4Ám, width: 1-2Ám). The average distance between the elements of the ornamentation is 1-2Ám. A conspicuous kidney-shaped ornament with low relief is always present ventrally on the endophragm, beneath the point of operculum attachment (Plate III, 1, 5). The archeopyle is apical, type tA. The peri- and endoperculum usually are attached by means of a narrow hinge (width: ca. 5Ám, Plate III, 8). The position of the parasulcus is indicated by a kidney-shaped ornament on the endophragm, and sometimes by a longitudinal fold in the periphragm. The paracingulum and the larger adcingular paraplates occasionally are indicated by folds in the periphragm. The paratabulation occurs inconsistently and has not been determined.
Dimensions [in Ám, 15 specimens measured, dimensions given as holotype, minimum (mean) maximum]: length of pericyst, 44, 39 (44) 55; width of pericyst, 37, 33 (40) 47; length of endocyst, 34, 32 (41) 52; width of endocyst, 31, 30 (38) 44.
Discussion: Schioler et al. 1997, p. 87
Leberidocysta? verrucosa differs from Leberidocysta chlamydata (Cookson & Eisenack, 1962) Stover & Evitt, 1978 by its smaller size, its usually attached opercula and the presence of a kidney-shaped ornament on the endophragm, and from all other species of the genus in having large verrucae or vermiculae on the endophragm. Form X sp. I of Marheinecke ( 1992) closely resembles the new species in form and size, but has an alveolate endophragm. Leberidocysta? flagellichnia Schi01er, 1993 differs in having a granulate endophragm. Leberidocysta? microverrucosa Slimani, 1994 also has a granulate endophragm, judged from photographs of the holotype, and probably is conspecific with L.? flagellichnia. All these species may represent a morphological continuum between specimens with a smooth-walled to granulate endophragm and specimens characterized by coarser ornamentation such as vermiculae, verrucae and alveoli. However, until more is known about their stratigraphic distribution we prefer to keep them separate.
Stratigraphic occurrence: Upper Maastrichtian, Upper Cretaceous of the ENCI Quarry, Maastricht, The Netherlands. Rare in the Lixhe members, absent above.
Questionable assignment: Schiøler et al. (1997, p.85).
Taxonomic senior synonym: Leberidocysta? microverrucosa, according to Slimani (2001a, p.193).
Holotype: Schioler et al. 1997: GEUS Catalogue No. 1996-PS-6 (Plate III, 1-3).
Paratypes: Schioler et al. 1997: GEUS Catalogue nos 1996-PS-7 (Plate III, 4,5), 1996-PS-8 (Plate III, 6-8).
Type locality: ENCI Quarry, Maastricht, The Netherlands.
Type stratum: ENCI Quarry section 0.0 m, Lixhe 2 Member, upper Maastrichtian, Upper Cretaceous.
Diagnosis: Schioler et al. 1997, p. 85, 87
Small oval to subspherical holocavate cyst with a thin, smooth periphragm. The periphragm occasionally has folds which indicate parts of the paratabulation. The endophragm is relatively thick-walled and verrucate to vermiculate. A kidney-shaped ornament is always present ventrally on the endocyst in the sulcal area. The archeopyle is apical, type tA; the operculum is usually attached.
Description: Schioler et al. 1997, p. 87
The periphragm is thin and smooth, and is separated from the endophragm by a narrow (3-8Ám) pericoel
which usually is broadest in the antapical area (Plate III, 2, 7). The endophragm is relatively thick-walled (ca. 2 ,um) and ornamented by verrucae (diameter: 1-3Ám) or vermiculae (length: 3-4Ám, width: 1-2Ám). The average distance between the elements of the ornamentation is 1-2Ám. A conspicuous kidney-shaped ornament with low relief is always present ventrally on the endophragm, beneath the point of operculum attachment (Plate III, 1, 5). The archeopyle is apical, type tA. The peri- and endoperculum usually are attached by means of a narrow hinge (width: ca. 5Ám, Plate III, 8). The position of the parasulcus is indicated by a kidney-shaped ornament on the endophragm, and sometimes by a longitudinal fold in the periphragm. The paracingulum and the larger adcingular paraplates occasionally are indicated by folds in the periphragm. The paratabulation occurs inconsistently and has not been determined.
Dimensions [in Ám, 15 specimens measured, dimensions given as holotype, minimum (mean) maximum]: length of pericyst, 44, 39 (44) 55; width of pericyst, 37, 33 (40) 47; length of endocyst, 34, 32 (41) 52; width of endocyst, 31, 30 (38) 44.
Discussion: Schioler et al. 1997, p. 87
Leberidocysta? verrucosa differs from Leberidocysta chlamydata (Cookson & Eisenack, 1962) Stover & Evitt, 1978 by its smaller size, its usually attached opercula and the presence of a kidney-shaped ornament on the endophragm, and from all other species of the genus in having large verrucae or vermiculae on the endophragm. Form X sp. I of Marheinecke ( 1992) closely resembles the new species in form and size, but has an alveolate endophragm. Leberidocysta? flagellichnia Schi01er, 1993 differs in having a granulate endophragm. Leberidocysta? microverrucosa Slimani, 1994 also has a granulate endophragm, judged from photographs of the holotype, and probably is conspecific with L.? flagellichnia. All these species may represent a morphological continuum between specimens with a smooth-walled to granulate endophragm and specimens characterized by coarser ornamentation such as vermiculae, verrucae and alveoli. However, until more is known about their stratigraphic distribution we prefer to keep them separate.
Stratigraphic occurrence: Upper Maastrichtian, Upper Cretaceous of the ENCI Quarry, Maastricht, The Netherlands. Rare in the Lixhe members, absent above.