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Glaphyrocysta semitecta
Glaphyrocysta semitecta (Bujak in Bujak et al., 1980, p.46,48,50, pl.14, figs.2-9; text-fig.13) Lentin and Williams, 1981, p.111.
Originally Cyclonephelium, subsequently (and now) Glaphyrocysta, thirdly Riculacysta (combination not validly published). Lentin and Williams (1993, p.238) retained this species in Glaphyrocysta.
Taxonomic senior synonym: Riculacysta perforata, according to Köthe (1990, p.50) - however, Kirsch (1991, p.129), retained Cyclonephelium (as Riculacysta, now Glaphyrocysta) semitectum.
Holotype: Bujak et al., 1980, pl.14, figs.4-6; Fauconnier and Masure, 2004, pl.33, figs.10-11.
Age: Mid Eocene (see Aubry, 1986).
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Glaphyrocysta semitecta (Bujak in Bujak et al., 1980) Lentin and Williams, 1981. According to Bujak in Bujak et al. (1980), Glaphyrocysta semitecta has simple fibrous processes arising from the central body periphery and two of the ventral precingular plates, which support a perforate membrane. The membrane is present around the dorsal side and is absent from most of the ventral side. It arises from a subquadrate middorsal area, where it is in contact with the central body. The membrane is highest antapically and lessens progressively towards the apex. The ventral border of the membrane is entire and occurs near the processes. The membrane arises from the anterior border of the dorsal zone of contact and forms a striate flange which extends anteriorly beyond the archeopyle suture, terminating in a straight or undulating margin. There may also be additional small spines on the ventral surface. Size: Loisthocyst 33-52 µm, width 45-60 µm, maximum process length 15-37 µm. Maximum membrane height 24-46 µm.
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Original description: Bujak in Bujak et al., 1980, p. 48, 50: Cyclonephelium? semitectum
Diagnosis: Cysts with spherical to ovoidal central body which amy have two antapical lobes. Central body surface granulate or reticulate. Simple fibrous processes arising from the central body periphery and two of the ventral precingular paraplates, support a perforate membrane. The membrane is present around the dorsal side of the cyst and is absent from most of the ventral side. It arises from a subquadrate middorsal area, where it is in contact with the central body. The height of the membrane is greatest antapically and lessens progressively towards the apex. The ventral border of the membrane is entire and occurs near the processes. The membrane rises from the anterior border of the dorsal zone of contact and forms a striate flange which extends anteriorly beyond the archaeopyle suture terminating in a straight or undulating entire margin. Additional small simple ventral processes may be present and are distally free. No dorsal precingular processes were observed. The archaeopyle is apical, tetratabular. The operculum has up to four processes and a high perforate distal membrane.
Dimensions: Central body length (without operculum) 33-52 µm, breadth 45-60 µm. Maximum process length 15-37 µm, maximum membrane height 25-46 µm. 40 specimens measured.
Affinities:
Bujak in Bujak et al., 1980, p. 50
Weyns (1970) figured a specimen of Cyclonephelium semitectum as C. exuberans 'ellipsoidale', but did not describe the subspecies or refer it to a previous author. C. semitectum is characterized by the high perforate membrane which covers the dorsal side of the cyst, other than the middorsal area, and is absent from the midventral region.
Originally Cyclonephelium, subsequently (and now) Glaphyrocysta, thirdly Riculacysta (combination not validly published). Lentin and Williams (1993, p.238) retained this species in Glaphyrocysta.
Taxonomic senior synonym: Riculacysta perforata, according to Köthe (1990, p.50) - however, Kirsch (1991, p.129), retained Cyclonephelium (as Riculacysta, now Glaphyrocysta) semitectum.
Holotype: Bujak et al., 1980, pl.14, figs.4-6; Fauconnier and Masure, 2004, pl.33, figs.10-11.
Age: Mid Eocene (see Aubry, 1986).
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G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Glaphyrocysta semitecta (Bujak in Bujak et al., 1980) Lentin and Williams, 1981. According to Bujak in Bujak et al. (1980), Glaphyrocysta semitecta has simple fibrous processes arising from the central body periphery and two of the ventral precingular plates, which support a perforate membrane. The membrane is present around the dorsal side and is absent from most of the ventral side. It arises from a subquadrate middorsal area, where it is in contact with the central body. The membrane is highest antapically and lessens progressively towards the apex. The ventral border of the membrane is entire and occurs near the processes. The membrane arises from the anterior border of the dorsal zone of contact and forms a striate flange which extends anteriorly beyond the archeopyle suture, terminating in a straight or undulating margin. There may also be additional small spines on the ventral surface. Size: Loisthocyst 33-52 µm, width 45-60 µm, maximum process length 15-37 µm. Maximum membrane height 24-46 µm.
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Original description: Bujak in Bujak et al., 1980, p. 48, 50: Cyclonephelium? semitectum
Diagnosis: Cysts with spherical to ovoidal central body which amy have two antapical lobes. Central body surface granulate or reticulate. Simple fibrous processes arising from the central body periphery and two of the ventral precingular paraplates, support a perforate membrane. The membrane is present around the dorsal side of the cyst and is absent from most of the ventral side. It arises from a subquadrate middorsal area, where it is in contact with the central body. The height of the membrane is greatest antapically and lessens progressively towards the apex. The ventral border of the membrane is entire and occurs near the processes. The membrane rises from the anterior border of the dorsal zone of contact and forms a striate flange which extends anteriorly beyond the archaeopyle suture terminating in a straight or undulating entire margin. Additional small simple ventral processes may be present and are distally free. No dorsal precingular processes were observed. The archaeopyle is apical, tetratabular. The operculum has up to four processes and a high perforate distal membrane.
Dimensions: Central body length (without operculum) 33-52 µm, breadth 45-60 µm. Maximum process length 15-37 µm, maximum membrane height 25-46 µm. 40 specimens measured.
Affinities:
Bujak in Bujak et al., 1980, p. 50
Weyns (1970) figured a specimen of Cyclonephelium semitectum as C. exuberans 'ellipsoidale', but did not describe the subspecies or refer it to a previous author. C. semitectum is characterized by the high perforate membrane which covers the dorsal side of the cyst, other than the middorsal area, and is absent from the midventral region.