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Achomosphaera andalousiensis
From Fensome et al., 2019:
Achomosphaera andalousiensis, Jan du Chêne, 1977, p.112, pl.1, figs.1–4.
Emendation: Jan du Chêne and Londeix, 1988, p.239, as Achomosphaera andalousiensis.
Holotype: Jan du Chêne, 1977, pl.1, fig.1, lost according to Jan du Chêne and Londeix (1988, p.237).
Lectotype: Jan du Chêne and Londeix, 1988, pl.1, figs.1–3, designated by Jan du Chêne and Londeix (1988, p.244). Originally (and now) Achomosphaera, subsequently Spiniferites. Head (1997, p.169) retained this species in Achomosphaera.
Taxonomic junior synonyms: Spiniferites septentrionalis, according to Harland (1983, p.103–104) — however, Londeix et al. (2009, p.67–68) retained Spiniferites septentrionalis, following an earlier suggestion by Head and Wrenn (1992, p.2); Spiniferites aquilonius, according to Strauss in Strauss and Lund (1992, p.169) — however, the latter species is now considered a taxonomic junior synonym of Spiniferites septentrionalis; Achomosphaera ramulifera subsp. perforata, according to Morzadec-Kerfourn (1979, p.224) as a senior synonym; however, Mertens et al. (2018a, p.11) did not accept this synonymy.
Age: Miocene (Andalusian).
Locus typicus: Carmona, Andalusia, Spain
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Original description: [Jan du Chene 1977, p. 112] (Translation: LPP):
Description:
The cyst has an ovoidal central body, with a precingular opening. The processes are long, slender, formed by the extension of the outer cyst layer. No sutural ridges are observed. Distally the processes are complex, first trifurcate, then in the form of closed, large-mesh reticules. Every external corner of the reticule bears a slender spine.
Dimensions:
Central body: 40 x 35 μm. Length of processes up to the base of the reticule: 15 μm. Size of reticule: up to 20 μm.
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Emended description:
Jan du Chene, R. and Londeix, L. 1988, p. 239:
Description:
Spiniferate cyst with an ellipsoidal central body, the wall of which consists of a very delicate and smooth endophragm and a thicker smooth to chagrinate periphragm. The endophragm and periphragm are strongly appressed, except below the processes that are formed exclusively by the periphragm. These gonal processes are long, generally slender, with a long subconical or truncate shaft, straight, hollow, sometimes fenestrate at the base. Their distal part is complex, first trifurcate (sometimes bifurcate or tetrafurcate), then bifurcate, every single subdivision being connected to its neighbours by a thin trabecule, thus forming a reticulum, each corner of which is ornamented with a spine or spur.
Parasutural septa are absent, but the gonyaulacoidal paratabulation is reflected by the gonal position of the processes and by the position of the precingular archaeopyle, type P(3''); the operculum is free.
The processes emerging from two adjacent triple junctions, e.g. those delimiting the apical and precingular paraplates, are often proximally interconnected, or even over their entire length. These processes seem to be more massive than the others, and their distal parts are more complex.
The parasulcus is reflected by the presence of a small number of clearly more slender and distally bifid processes.
Affinities (p. 241):
Harland 1983 designated Spiniferites septentrionalis Harland 1977 as a jr synonym of Achomosphaera andalousiensis. Although the distal parts of the processes seem to be less complex and less extensively subdivided in S. septentrionalis, and because the holotype of latter species could not be studied, this synonymy is maintained.
Spiniferites speetonensis Duxbury 1980 has processes similar to those of A. andalousiensis, but differs from it in the possession of low septa and intragonal processes.
Spiniferites perforatus (Davey and Williams 1966) Sarjeant 1970 also has parasutural septa that may be relatively high, locally, and sutural proceses (see holotype in Bujak et al. 1980).
Achomosphaera ramulifera perforata (Davey and Williams 1966) Lentin and Williams 1973 is described with proximally and sometimes also distally fenestrate processes, but may show parasutural septa, and the extremities of the distal furcations of its processes are not distally connected by trabeculae (see holotype in Bujak et al. 1980).
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Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Achomosphaera andalousiensis Jan du Chêne, 1977 emend. Jan du Chêne and Londeix, 1988. This species can have processes that are fenestrate proximally. The distal extremities are complex, first trifurcate (sometimes bifurcate or tetrafurcate), then bifurcate, each of the final furcations being connected to the nearest ones by narrow trabeculae. These trabeculae form a polygonal reticulum with a spine at each angle. Processes emerging from two adjacent triple junctions are often connected proximally, partly, or along all their length. These processes appear more massive than the regular ones and their extremities are more complicated. Narrow processes with a bifid tip characterize the sulcal area. Central body 40 x 35 µm.
Achomosphaera andalousiensis, Jan du Chêne, 1977, p.112, pl.1, figs.1–4.
Emendation: Jan du Chêne and Londeix, 1988, p.239, as Achomosphaera andalousiensis.
Holotype: Jan du Chêne, 1977, pl.1, fig.1, lost according to Jan du Chêne and Londeix (1988, p.237).
Lectotype: Jan du Chêne and Londeix, 1988, pl.1, figs.1–3, designated by Jan du Chêne and Londeix (1988, p.244). Originally (and now) Achomosphaera, subsequently Spiniferites. Head (1997, p.169) retained this species in Achomosphaera.
Taxonomic junior synonyms: Spiniferites septentrionalis, according to Harland (1983, p.103–104) — however, Londeix et al. (2009, p.67–68) retained Spiniferites septentrionalis, following an earlier suggestion by Head and Wrenn (1992, p.2); Spiniferites aquilonius, according to Strauss in Strauss and Lund (1992, p.169) — however, the latter species is now considered a taxonomic junior synonym of Spiniferites septentrionalis; Achomosphaera ramulifera subsp. perforata, according to Morzadec-Kerfourn (1979, p.224) as a senior synonym; however, Mertens et al. (2018a, p.11) did not accept this synonymy.
Age: Miocene (Andalusian).
Locus typicus: Carmona, Andalusia, Spain
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Original description: [Jan du Chene 1977, p. 112] (Translation: LPP):
Description:
The cyst has an ovoidal central body, with a precingular opening. The processes are long, slender, formed by the extension of the outer cyst layer. No sutural ridges are observed. Distally the processes are complex, first trifurcate, then in the form of closed, large-mesh reticules. Every external corner of the reticule bears a slender spine.
Dimensions:
Central body: 40 x 35 μm. Length of processes up to the base of the reticule: 15 μm. Size of reticule: up to 20 μm.
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Emended description:
Jan du Chene, R. and Londeix, L. 1988, p. 239:
Description:
Spiniferate cyst with an ellipsoidal central body, the wall of which consists of a very delicate and smooth endophragm and a thicker smooth to chagrinate periphragm. The endophragm and periphragm are strongly appressed, except below the processes that are formed exclusively by the periphragm. These gonal processes are long, generally slender, with a long subconical or truncate shaft, straight, hollow, sometimes fenestrate at the base. Their distal part is complex, first trifurcate (sometimes bifurcate or tetrafurcate), then bifurcate, every single subdivision being connected to its neighbours by a thin trabecule, thus forming a reticulum, each corner of which is ornamented with a spine or spur.
Parasutural septa are absent, but the gonyaulacoidal paratabulation is reflected by the gonal position of the processes and by the position of the precingular archaeopyle, type P(3''); the operculum is free.
The processes emerging from two adjacent triple junctions, e.g. those delimiting the apical and precingular paraplates, are often proximally interconnected, or even over their entire length. These processes seem to be more massive than the others, and their distal parts are more complex.
The parasulcus is reflected by the presence of a small number of clearly more slender and distally bifid processes.
Affinities (p. 241):
Harland 1983 designated Spiniferites septentrionalis Harland 1977 as a jr synonym of Achomosphaera andalousiensis. Although the distal parts of the processes seem to be less complex and less extensively subdivided in S. septentrionalis, and because the holotype of latter species could not be studied, this synonymy is maintained.
Spiniferites speetonensis Duxbury 1980 has processes similar to those of A. andalousiensis, but differs from it in the possession of low septa and intragonal processes.
Spiniferites perforatus (Davey and Williams 1966) Sarjeant 1970 also has parasutural septa that may be relatively high, locally, and sutural proceses (see holotype in Bujak et al. 1980).
Achomosphaera ramulifera perforata (Davey and Williams 1966) Lentin and Williams 1973 is described with proximally and sometimes also distally fenestrate processes, but may show parasutural septa, and the extremities of the distal furcations of its processes are not distally connected by trabeculae (see holotype in Bujak et al. 1980).
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Notes:
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Achomosphaera andalousiensis Jan du Chêne, 1977 emend. Jan du Chêne and Londeix, 1988. This species can have processes that are fenestrate proximally. The distal extremities are complex, first trifurcate (sometimes bifurcate or tetrafurcate), then bifurcate, each of the final furcations being connected to the nearest ones by narrow trabeculae. These trabeculae form a polygonal reticulum with a spine at each angle. Processes emerging from two adjacent triple junctions are often connected proximally, partly, or along all their length. These processes appear more massive than the regular ones and their extremities are more complicated. Narrow processes with a bifid tip characterize the sulcal area. Central body 40 x 35 µm.