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Apectodinium folliculum
From Fensome et al., 2019:
Apectodinium folliculum, Islam, 1983b, p.336–337, pl.1, figs.8–9.
Holotype: Islam, 1983b, pl.1, fig.8.
Taxonomic senior synonym: Wetzeliella (now Apectodinium) homomorpha, according to Williams et al. (1993, p.57).
Age: Early-Middle Eocene.
Locus typicus: Hampshire Basin, S England
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Original description: [Islam, 1983, p. 336-337]:
Diagnosis:
Cyst ambitus subcircular to elliptical or roundly pentagonal without horns or with very minor ones; acavate to slightly cornucavate; proximochorate; periphragm mildly chagrinate; many, sometimes fewer, nontabular processes thin, solid and thinly tubular, slender to somewhat flexible, distally aculeate and open when hollow, proximally wide and sometimes joining in groups; paracingulum generally not indicated; archeopyle intercalary type lll but generally indistinguishable, its absence in subspherical forms, making orientation difficult.
Dimensions:
Holotype: cyst body 54 x 56 µm, length of processes 5-8 µm.
Range: cyst length 68(53)42 µm, breadth 62(52)42 µm, length of processes 3-13 µm. Specimens measured: 10.
Affinities:
This species differs from others of the genus in possessing a roundish cyst with vestigial horns or, generally, being without horns. In process morphology it resembles Apectodinium summissum Harland 1980 and Trivalvadinium formosum Islam and may be related to both species. The former species differs in possessing two antapical horns, the latter in possessing a 3I archeopyle.
Apectodinium folliculum, Islam, 1983b, p.336–337, pl.1, figs.8–9.
Holotype: Islam, 1983b, pl.1, fig.8.
Taxonomic senior synonym: Wetzeliella (now Apectodinium) homomorpha, according to Williams et al. (1993, p.57).
Age: Early-Middle Eocene.
Locus typicus: Hampshire Basin, S England
---------------------------------------------------------------------------------------------------
Original description: [Islam, 1983, p. 336-337]:
Diagnosis:
Cyst ambitus subcircular to elliptical or roundly pentagonal without horns or with very minor ones; acavate to slightly cornucavate; proximochorate; periphragm mildly chagrinate; many, sometimes fewer, nontabular processes thin, solid and thinly tubular, slender to somewhat flexible, distally aculeate and open when hollow, proximally wide and sometimes joining in groups; paracingulum generally not indicated; archeopyle intercalary type lll but generally indistinguishable, its absence in subspherical forms, making orientation difficult.
Dimensions:
Holotype: cyst body 54 x 56 µm, length of processes 5-8 µm.
Range: cyst length 68(53)42 µm, breadth 62(52)42 µm, length of processes 3-13 µm. Specimens measured: 10.
Affinities:
This species differs from others of the genus in possessing a roundish cyst with vestigial horns or, generally, being without horns. In process morphology it resembles Apectodinium summissum Harland 1980 and Trivalvadinium formosum Islam and may be related to both species. The former species differs in possessing two antapical horns, the latter in possessing a 3I archeopyle.