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Lejeunecysta diversiforma ssp. muscatensis
Lejeunecysta diversiforma ssp. muscatensis (Bradford, 1977) Artzner and D÷rh÷fer, 1978
Originally Lejeunia diversiforma ssp. muscatensis (name illegitimate), subsequently (and now) Lejeunecysta diversiforma ssp. muscatensis
Holotype: Bradford, 1977, fig.6:3
Age: Recent
Original description, Bradford, 1977: Lejeunia diversiforma subsp. muscatense subsp. nov. (Fig. 6: 1-3)
Derivation of name: "of Muscat"; the State of Muscat is the nearest land to the sample which yields the only specimens of this new subspecies.
DIAGNOSIS
Shape: Pericyst: Pentagonal in ambitus and frequently circular in polar view. Two distinct antapical horns are present; these horns are equally developed and are rounded distally. The antapical depression is either moderately deep or deep. The hypopericyst sides are convex. The epipericyst has convex sides with very distinct shoulders and a small apical horn or boss. Endocyst: Not observed, appressed closely to pericyst throughout. Pericoel: Not observed.
Phragma: Both layers are very thin, with laevigate-to-shagreenate ornamentation; numerous folds and light longitudinal striations are often present. Both layers of constant thickness, apart from the diagnostic antapical thickening. At the distal terminations of the antapical horns, two distinct areas of periphragm thickening were observed in each horn. No other thickening was observed in the remaining sections of the tract.
Paratabulation: Pericyst: Paratabulation indeterminate. Pericingulum: represents the broadest part of the tract; it is narrow and delineated usually by folds in the periphragm. Perisulcus: is usually shallow but broad. Endocyst: Paratabulation indeterminate.
Archeopyle: Standard hexa resulting from the detachment of the 2a anterior intercalary paraplate. Since the periphragm and endophragm are generally appressed in this area of the tract, there appear to be one archeopyle and one operculum; the operculum often remains in place. Archeopyle Formula (l/l(2a/2a).
DIMENSIONS
Holotype-length 79 μm, breadth 72 μm, distance between antapical horns (distally) 21 µm. Other specimens-length 68-99 μm, breadth 72-94 μm, distance between antapical horns (distally) 17-40 μm. Number of specimens measured: 10.
HOLOTYPE
206(4) 110.8 x 5.3; slide number G.M.U.S. Pd. 21, housed in the Palynology Collection of the Geology Museum, University of Saskatchewan. Locality: Recent sediments, water depth 1948 metres, off the Ras al Hadd, Muscat, Northern Arabian Sea 22°24'06"N, 60°09'12"E. Sample collected in 1933, by HMES Mabahiss on the John Murray Expedition, and obtained from the Department of Mineralogy (Oceanographic Section), British Museum (Natural History), London. (B.M. (N.H.) sample 96626(4) st. no. 59.)
REMARKS
This subspecies differs from the typical forms of L. diversiforma sp. nov. in having distinct antapical processes with characteristic twin distal periphragm thickenings. The antapical depression is usually moderately deep; the periphragm is very thin and consistently lacks the microgranular texture of L. diversiforma.
THECAL AFFINITY
Unknown, however, it shows peridinioid characters.
OCCURRENCE
Only found in one sample (206) which was collected off the coast of Ras al Hadd, Muscat, in the Northern Arabian Sea at a depth of 1948 metres.
Originally Lejeunia diversiforma ssp. muscatensis (name illegitimate), subsequently (and now) Lejeunecysta diversiforma ssp. muscatensis
Holotype: Bradford, 1977, fig.6:3
Age: Recent
Original description, Bradford, 1977: Lejeunia diversiforma subsp. muscatense subsp. nov. (Fig. 6: 1-3)
Derivation of name: "of Muscat"; the State of Muscat is the nearest land to the sample which yields the only specimens of this new subspecies.
DIAGNOSIS
Shape: Pericyst: Pentagonal in ambitus and frequently circular in polar view. Two distinct antapical horns are present; these horns are equally developed and are rounded distally. The antapical depression is either moderately deep or deep. The hypopericyst sides are convex. The epipericyst has convex sides with very distinct shoulders and a small apical horn or boss. Endocyst: Not observed, appressed closely to pericyst throughout. Pericoel: Not observed.
Phragma: Both layers are very thin, with laevigate-to-shagreenate ornamentation; numerous folds and light longitudinal striations are often present. Both layers of constant thickness, apart from the diagnostic antapical thickening. At the distal terminations of the antapical horns, two distinct areas of periphragm thickening were observed in each horn. No other thickening was observed in the remaining sections of the tract.
Paratabulation: Pericyst: Paratabulation indeterminate. Pericingulum: represents the broadest part of the tract; it is narrow and delineated usually by folds in the periphragm. Perisulcus: is usually shallow but broad. Endocyst: Paratabulation indeterminate.
Archeopyle: Standard hexa resulting from the detachment of the 2a anterior intercalary paraplate. Since the periphragm and endophragm are generally appressed in this area of the tract, there appear to be one archeopyle and one operculum; the operculum often remains in place. Archeopyle Formula (l/l(2a/2a).
DIMENSIONS
Holotype-length 79 μm, breadth 72 μm, distance between antapical horns (distally) 21 µm. Other specimens-length 68-99 μm, breadth 72-94 μm, distance between antapical horns (distally) 17-40 μm. Number of specimens measured: 10.
HOLOTYPE
206(4) 110.8 x 5.3; slide number G.M.U.S. Pd. 21, housed in the Palynology Collection of the Geology Museum, University of Saskatchewan. Locality: Recent sediments, water depth 1948 metres, off the Ras al Hadd, Muscat, Northern Arabian Sea 22°24'06"N, 60°09'12"E. Sample collected in 1933, by HMES Mabahiss on the John Murray Expedition, and obtained from the Department of Mineralogy (Oceanographic Section), British Museum (Natural History), London. (B.M. (N.H.) sample 96626(4) st. no. 59.)
REMARKS
This subspecies differs from the typical forms of L. diversiforma sp. nov. in having distinct antapical processes with characteristic twin distal periphragm thickenings. The antapical depression is usually moderately deep; the periphragm is very thin and consistently lacks the microgranular texture of L. diversiforma.
THECAL AFFINITY
Unknown, however, it shows peridinioid characters.
OCCURRENCE
Only found in one sample (206) which was collected off the coast of Ras al Hadd, Muscat, in the Northern Arabian Sea at a depth of 1948 metres.