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Muraticysta microornata
Muraticysta microornata Head et al., 1989
Originally Muraticysta, subsequently (and now) Filisphaera.
Holotype: Head et al., 1989, pl.5, fig.1-3,5
Locus typicus: ODP leg 105, site 646
Stratum typicum: Early Pliocene
Original diagnosis: Head et al., 1989, p.458
Cysts spherical to ovoidal with a closely appressed biphragmal wall. Endophragm thinner than periphragm, which forms a smooth reticulate ornament of fine, delicate sinuous muri 2-3 Ám high that have slightly undulating crest tops. Lacunae have an irregular polygonal outline and are about 1.5-3.5 Ám wide. Archeopyle precingular Type P (presumably Type P3"") and large. Operculum free. There is no other indication of paratabulation.
Dimensions. Holotype: maximum diameter, 57 Ám. Range of maximum diameter, 53(58)62 Ám; muri 2-3 Ám high and 0.2-0.5 Ám wide. Nine specimens were measured.
Remarks. In all specimens where the archeopyle could be recognized, Type P was observed.
Affinities:
Head et al., 1989, p.458-459: This species is similar in size and shape to Filisphara filifera Bujak, 1984 and differs in having a finely reticulate periphragm, compared to the radially fibrous periphragm of F. filifera (Bujak, 1984, p. 185). However, these two species may appear similar under low magnification. F. filifera may also possess a small apical lobe, and the archeopyle may involve the loss of one or two precingular paraplates. It was not possible to determine whether a slight apical lobe is present in M. microornata n. sp. because of the folded condition of most specimens encountered.
Originally Muraticysta, subsequently (and now) Filisphaera.
Holotype: Head et al., 1989, pl.5, fig.1-3,5
Locus typicus: ODP leg 105, site 646
Stratum typicum: Early Pliocene
Original diagnosis: Head et al., 1989, p.458
Cysts spherical to ovoidal with a closely appressed biphragmal wall. Endophragm thinner than periphragm, which forms a smooth reticulate ornament of fine, delicate sinuous muri 2-3 Ám high that have slightly undulating crest tops. Lacunae have an irregular polygonal outline and are about 1.5-3.5 Ám wide. Archeopyle precingular Type P (presumably Type P3"") and large. Operculum free. There is no other indication of paratabulation.
Dimensions. Holotype: maximum diameter, 57 Ám. Range of maximum diameter, 53(58)62 Ám; muri 2-3 Ám high and 0.2-0.5 Ám wide. Nine specimens were measured.
Remarks. In all specimens where the archeopyle could be recognized, Type P was observed.
Affinities:
Head et al., 1989, p.458-459: This species is similar in size and shape to Filisphara filifera Bujak, 1984 and differs in having a finely reticulate periphragm, compared to the radially fibrous periphragm of F. filifera (Bujak, 1984, p. 185). However, these two species may appear similar under low magnification. F. filifera may also possess a small apical lobe, and the archeopyle may involve the loss of one or two precingular paraplates. It was not possible to determine whether a slight apical lobe is present in M. microornata n. sp. because of the folded condition of most specimens encountered.