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Cyclonephelium distinctum var. distinctum
Cyclonephelium distinctum var. distinctum
Autonym. Now redundant.
Cookson and Eisenack, 1974, p.74
As shown by us, in particular in our 1962 paper, the C. distinctum is a greatly varying species. This becomes again apparent, mainly in the Balcatta bore. An extreme form is the specimen figured in Figure 7. We do not consider it as appropriate to separate further variants on the basis of the more or less developed processes.The processes occasionally extend very far from the margin of the shell toward the middle. Since, on one and the same specimen, they can moreover greatly vary in form, a close relationship to the Heterosphaeridium heteracanthum (Defl. & Cooks. 1955) seems to be involved here.
Original description: Deflandre and Cookson, 1955, p. 285-286
Ornamentation typically consisting of numerous short, solid appendages of variable width, the apices of which are either bluntly pointed, capitate, enlarged, or forked; rarely the processes are joined to one another forming short lamellae. They are irregularly disposed, most numerous at the equator and becoming progressively fewer towards the poles, from which they are entirely absent. Surface of shell distinctly punctate.
Autonym. Now redundant.
Cookson and Eisenack, 1974, p.74
As shown by us, in particular in our 1962 paper, the C. distinctum is a greatly varying species. This becomes again apparent, mainly in the Balcatta bore. An extreme form is the specimen figured in Figure 7. We do not consider it as appropriate to separate further variants on the basis of the more or less developed processes.The processes occasionally extend very far from the margin of the shell toward the middle. Since, on one and the same specimen, they can moreover greatly vary in form, a close relationship to the Heterosphaeridium heteracanthum (Defl. & Cooks. 1955) seems to be involved here.
Original description: Deflandre and Cookson, 1955, p. 285-286
Ornamentation typically consisting of numerous short, solid appendages of variable width, the apices of which are either bluntly pointed, capitate, enlarged, or forked; rarely the processes are joined to one another forming short lamellae. They are irregularly disposed, most numerous at the equator and becoming progressively fewer towards the poles, from which they are entirely absent. Surface of shell distinctly punctate.