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Lejeunecysta cinctoria

Lejeunecysta cinctoria (Bujak in Bujak et al., 1980) Lentin and Williams, 1981

Originally Lejeunia (an illegitimate generic name), subsequently (and now) Lejeunecysta.

Holotype: Bujak in Bujak et al., 1980, pl. 18, fig. 1-2
Paratypes: Bujak in Bujak et al., 1980
Locus typicus: White Cliff Bay, Isle of Wight, S England
Stratum typicum: Late Eocene

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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.

Lejeunecysta cinctoria (Bujak in Bujak et al., 1980) Lentin and Williams, 1981. According to Bujak in Bujak et al. (1980), Lejeunecysta cinctoria has a peridinioid autocyst with pentagonal ambitus. The epicyst and hypocyst are of about the same length. The apex is rounded, truncated or has a small distinct boss. Two approximately equal, symmetrically located antapical horns are present or absent. When present, the horns are pointed and solid. Autophragm laevigate to chagrinate. Spines are always present on the paracingular margins. They may also be at the apex, ambital periphery and often form a curved row between the antapical horns. Spines are solid, short, proximally expanded, simple or bifid, and often vary in shape and size on the same specimen. The planar or slightly helicoidal cingulum is delimited by two folds and a shallow indentation. The folds are distally spinate and may be continuous or partite, when there are seven precingular and five postcingular divisions. Archeopyle resulting from loss of 2a, extends almost to cingulum. Operculum free or remains attached along the posterior margin. Transverse archeopyle index 0.37-0.42, longitudinal archeopyle index 0.68-0.78, archeopyle ratio 0.9-1.2. This species differs from L.paratenella in having spines on both the anterior and posterior margins of the cingulum. Size: length 44-62 µm, width 41-63 µm, spine length 3-4 µm.
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Original description: Bujak in Bujak et al., 1980, p.68- 69
Diagnosis: Autocyst peridinioid with dorsoventral compression and a pentagonal ambitus. The epicyst and hypocyst lengths are approximately equal. The apex is rounded, truncated, or has a small distinct boss. Two approximately equal, symmetrically located antapical horns are present or absent. When present, the horns are pointed and solid. Autophragm laevigate to chagrinate. Spines are always present on the paracingular margins. They may also be present at the apex, ambital periphery, and often form a curved row between the antapical horns. The spines are solid, short, proximally expanded, simple or bifid, and often vary in size and shape on a single specimen. Paratabulation is only indicated near the archaeopyle and paracingulum. The planar or sligthly helicoidal paracingulum is delimeted by two folds and shallow indentation. The folds are distally spinate and may be continuous or partite. When partite, the paracingulum is separated into seven anterior and five posterior divisions. The parasulcus is marked by a shallow depression. The archaeopyle is intercalary 2a and is symmetrically located on the middorsal line. It extends almost to the paracingulum. The operculum is free or remains attached along the posterior margin. Transverse archaeopyle index = 0.37-0.42, longitudinal archaeopyle index = 0.68-0.78, archaeopyle ratio = 0.9-1.2.

Dimensions: Autocyst length = 44-62 µm, breadth = 41-63 µm, maximum spine length = 3-4 µm. Number of specimens measured = 14.

Affinities:
Bujak in Bujak et al., 1980, p. 69
L. cinctoria differs from L. paratenella Benedek, 1972, in having spines on both the anterior and posterior paracingular margins.
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