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Exochosphaeridium masureae
From Fensome et al., 2019:
Exochosphaeridium? masureae Slimani, 1996, p.373–374, pl.1, figs.H–L ex Slimani, 2001b, p.2–3, pl.1, figs.1–2,4–5; pl.2, fig.10.
Holotype: Slimani, 1996, pl.1, figs.I,L; Slimani, 2001b, pl.1, figs.1–2. Questionable assignment: Slimani (1996, p.373; 2001b, p.2). Taxonomic junior synonym: Exochosphaeridium acuminatum (name not validly published), according to Slimani (2001a, p.192; 2001b, p.2). This name was not validly published in Slimani (1996) since no English or Latin description or diagnosis was provided. Age: Campanian.
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Original description in Slimani, 1996 (As Exochosphaeridium masurii, not yet translated from French)
Name derivation. In honor of Dr. Edwige Masure, Laboratory of Micropaleontology, Pierre and Marie Curie University, Paris, France.
Holotype. Turnhout -956 m, preparation 9, E.F. coord. V51/4; Pl. 1 Fig. I, L.
Paratype. Hallembaye sample 18, preparation 3, E.F. coord. F32/3; Pl. 1, Fig. H.
Type locality. Turnhout -956 m
Type horizon. Campanian.
Occurrence. Beutenaken: samples 1-11 (Lower Campanian - Upper Campanian); Hallembaye: samples 12 to 27 (Upper Campanian); Turnhout: -978 to -933 m (Upper Campanian).
Description. Skolochorate cyst, the central body is ovoid to spheroidal and bears numerous membranous processes. These are hollow, broad proximally, simple and accuminate distally, or divided into smaller accuminate processes. A section at their base shows that they have a dubsircular to oval cross-section, 2.5 to 10 µm in diameter. In some specimens, the processes are quite well developed and resemble those of some species of the genus Florentinia (see note below). The tabular distribution of the processes is clearer in some specimens than in others, but always remains unclear; There are apparently precingulate, paracingulate, postcingulate, and sulcal processes. The levorotatory paracingulate is often the best-expressed character in most specimens, indicated by an alignment of processes in two parallel rows separated by a distance of 4 to 6 µm. The preapical process is distinct; it is often solid and bears short, accuminate processes. The archaeopyle is precingulate of type P(3") with a free, isolated, or collapsed operculum within the central body.
Dimensions. Maximum diameter of the central body: holotype 65 µm; paratype, 50 µm; other specimens, 50-70 µm. Process length: holotype, 6-20 µm; paratype, 6-16 µm; other specimens, 6-14 µm. Number of specimens measured: 10.
Notes. This type of cyst is provisionally assigned to the genus Exochosphaeridium because its ornamentation makes the paratabulation so confusing that we cannot compare it with that of other genera. In the genus Exochosphaeridium, the cyst wall is fibro-punctate; this is not the case in the new species. The hollow structure of the processes brings this species closer to the genus Florentinia, especially Florentinia ferox (Deflandre, 1937) Duxbury (1980) and also Raetiaedinium belgicum Slimani (1994); but these last two species are distinguished from the present one mainly by their archaeopyle which is for Florentinia a combination of apical paraplates and a precingular paraplate, and for Raetiadinium precingular of type 2P. Exochosphaeridium? masurii sp. nov. corresponds well to the species described and figured for the first time under the name Exochosphaeridium? acuminatum by Wilson (1974). The same type of cyst has been found by other authors (see above), but published as Exochosphaeridium? acuminatum in Wilson (1974) without description or illustration.
Exochosphaeridium? masureae Slimani, 1996, p.373–374, pl.1, figs.H–L ex Slimani, 2001b, p.2–3, pl.1, figs.1–2,4–5; pl.2, fig.10.
Holotype: Slimani, 1996, pl.1, figs.I,L; Slimani, 2001b, pl.1, figs.1–2. Questionable assignment: Slimani (1996, p.373; 2001b, p.2). Taxonomic junior synonym: Exochosphaeridium acuminatum (name not validly published), according to Slimani (2001a, p.192; 2001b, p.2). This name was not validly published in Slimani (1996) since no English or Latin description or diagnosis was provided. Age: Campanian.
---------------------------------------------------------------------------------------------------
Original description in Slimani, 1996 (As Exochosphaeridium masurii, not yet translated from French)
Name derivation. In honor of Dr. Edwige Masure, Laboratory of Micropaleontology, Pierre and Marie Curie University, Paris, France.
Holotype. Turnhout -956 m, preparation 9, E.F. coord. V51/4; Pl. 1 Fig. I, L.
Paratype. Hallembaye sample 18, preparation 3, E.F. coord. F32/3; Pl. 1, Fig. H.
Type locality. Turnhout -956 m
Type horizon. Campanian.
Occurrence. Beutenaken: samples 1-11 (Lower Campanian - Upper Campanian); Hallembaye: samples 12 to 27 (Upper Campanian); Turnhout: -978 to -933 m (Upper Campanian).
Description. Skolochorate cyst, the central body is ovoid to spheroidal and bears numerous membranous processes. These are hollow, broad proximally, simple and accuminate distally, or divided into smaller accuminate processes. A section at their base shows that they have a dubsircular to oval cross-section, 2.5 to 10 µm in diameter. In some specimens, the processes are quite well developed and resemble those of some species of the genus Florentinia (see note below). The tabular distribution of the processes is clearer in some specimens than in others, but always remains unclear; There are apparently precingulate, paracingulate, postcingulate, and sulcal processes. The levorotatory paracingulate is often the best-expressed character in most specimens, indicated by an alignment of processes in two parallel rows separated by a distance of 4 to 6 µm. The preapical process is distinct; it is often solid and bears short, accuminate processes. The archaeopyle is precingulate of type P(3") with a free, isolated, or collapsed operculum within the central body.
Dimensions. Maximum diameter of the central body: holotype 65 µm; paratype, 50 µm; other specimens, 50-70 µm. Process length: holotype, 6-20 µm; paratype, 6-16 µm; other specimens, 6-14 µm. Number of specimens measured: 10.
Notes. This type of cyst is provisionally assigned to the genus Exochosphaeridium because its ornamentation makes the paratabulation so confusing that we cannot compare it with that of other genera. In the genus Exochosphaeridium, the cyst wall is fibro-punctate; this is not the case in the new species. The hollow structure of the processes brings this species closer to the genus Florentinia, especially Florentinia ferox (Deflandre, 1937) Duxbury (1980) and also Raetiaedinium belgicum Slimani (1994); but these last two species are distinguished from the present one mainly by their archaeopyle which is for Florentinia a combination of apical paraplates and a precingular paraplate, and for Raetiadinium precingular of type 2P. Exochosphaeridium? masurii sp. nov. corresponds well to the species described and figured for the first time under the name Exochosphaeridium? acuminatum by Wilson (1974). The same type of cyst has been found by other authors (see above), but published as Exochosphaeridium? acuminatum in Wilson (1974) without description or illustration.