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Wanaea thysanota
Wanaea thysanota Woollam, 1982
Holotype: Woollam, 1982, pl.2, fig.1
Locus typicus: Middle Oxford Clay, Woodham Brick Pit, Aylesbury, England
Stratum typicum: Late Callovian
Translation Courtinat, 1989: LPP
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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.
Wanaea thysanota Woollam, 1982. Diagnosis from Woollam (1982, p.48), Epicyst slightly apically convex, hypocyst broadly conical, with a short rounded antapical horn. Archeopyle epicystal, an equatorial line of schism partially separating the simple compound operculum (the entire epicyst), from the hypocyst. Cyst wall smooth, paratabulation generally absent, except for a prominent lace-like (posterior paracingular) equatorial flange which is interrupted along a line corresponding to the area of attachment of the operculum (parasulcus). The equatorial flange consists of radially arranged processes, varying in length from 10-20 µm, occasionally linked but generally free distally, simple, bifurcate or capitate, coalescing towards their bases to form a variably perforate crest. Size: not given.
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Original description: Woollam, 1982, p. 48
Diagnosis. Epicyst slightly apically convex, hypocyst broadly conical, with a short rounded antapical horn. Archaeopyle epicystal, an equatorial line of schism partially separating the simple compound operculum (the entire epicyst), from the hypocyst. Cyst wall smooth, paratabulation generally absent, except for a prominent lace-like (posterior paracingular) equatorial flange which is interrupted along a line corresponding to the area of attachment of the operculum (parasulcus). The equatorial flange consists of radially arranged processes, varying in length from 10 to 20 Ám, occassionally linked but generally free distally, simple, bifurcate or capitate, coalescing towards their bases to form a variably perforate crest.
Remarks: This species is erected to accommodate forms previously placed in Wanaea digitata, but which do not accord with the type material of the latter.
Courtinat, 1989, p.212: Remarks on Wanaea digitata and W. thysanota:
Fensome (1981) gave evidence for a possible phyletic relation between species of Wanaea and Energlynia. According to this scheme, W. spectabilis, W. digitata, W. thysanota, W. fimbriata and W. clathrata are different ends of the same lineage. Woollam (1982) thinks that such a sequence is difficult to accept because of the spatial and temporal distribution of these species. In the Jura, W. digitata and W. thysanota progressively shade off into one another, considering the ornamentation of the adcingular crests as morphological characteristic. Fensome's scheme does not appear unreal; it may be integrated in the framework of allopatric speciation.
Holotype: Woollam, 1982, pl.2, fig.1
Locus typicus: Middle Oxford Clay, Woodham Brick Pit, Aylesbury, England
Stratum typicum: Late Callovian
Translation Courtinat, 1989: LPP
--------------------------------------------------
G.L. Williams short notes on species, Mesozoic-Cenozoic dinocyst course, Urbino, Italy, May 17-22, 1999 - LPP VIEWER CD-ROM 99.5.
Wanaea thysanota Woollam, 1982. Diagnosis from Woollam (1982, p.48), Epicyst slightly apically convex, hypocyst broadly conical, with a short rounded antapical horn. Archeopyle epicystal, an equatorial line of schism partially separating the simple compound operculum (the entire epicyst), from the hypocyst. Cyst wall smooth, paratabulation generally absent, except for a prominent lace-like (posterior paracingular) equatorial flange which is interrupted along a line corresponding to the area of attachment of the operculum (parasulcus). The equatorial flange consists of radially arranged processes, varying in length from 10-20 µm, occasionally linked but generally free distally, simple, bifurcate or capitate, coalescing towards their bases to form a variably perforate crest. Size: not given.
--------------------------------------------------
Original description: Woollam, 1982, p. 48
Diagnosis. Epicyst slightly apically convex, hypocyst broadly conical, with a short rounded antapical horn. Archaeopyle epicystal, an equatorial line of schism partially separating the simple compound operculum (the entire epicyst), from the hypocyst. Cyst wall smooth, paratabulation generally absent, except for a prominent lace-like (posterior paracingular) equatorial flange which is interrupted along a line corresponding to the area of attachment of the operculum (parasulcus). The equatorial flange consists of radially arranged processes, varying in length from 10 to 20 Ám, occassionally linked but generally free distally, simple, bifurcate or capitate, coalescing towards their bases to form a variably perforate crest.
Remarks: This species is erected to accommodate forms previously placed in Wanaea digitata, but which do not accord with the type material of the latter.
Courtinat, 1989, p.212: Remarks on Wanaea digitata and W. thysanota:
Fensome (1981) gave evidence for a possible phyletic relation between species of Wanaea and Energlynia. According to this scheme, W. spectabilis, W. digitata, W. thysanota, W. fimbriata and W. clathrata are different ends of the same lineage. Woollam (1982) thinks that such a sequence is difficult to accept because of the spatial and temporal distribution of these species. In the Jura, W. digitata and W. thysanota progressively shade off into one another, considering the ornamentation of the adcingular crests as morphological characteristic. Fensome's scheme does not appear unreal; it may be integrated in the framework of allopatric speciation.