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February 2001
"Cycladophorids" are common and diverse in the Paleocene of ODP Site 1121, Campbell Plateau, SE of New Zealand. The taxon described and illustrated here is the most common, especially in the Late Paleocene (RP5-6). For expediency it is treated as a single species although it is quite conceivable that the range encompasses several species.

Cycladophora aff. cosma Lombari and Lazarus
aff. Cycladophora cosma cosma Lombari and Lazarus 1988, p. 104, pl. 1, fig. 1-6
aff. Clathrocycloma parcum Foreman 1973, p. 434, pl. 2, fig. 13; pl. 11, fig. 12.
Diplocyclas pseudobicorona pseudobicorona Nishimura, 1992 (in part), p. 340, pl. 4, fig. 5.

Description: Conical test of 2 segments. Small spheroidal cephalis has divergent apical and vertical horns; vertical horn is the same size or smaller than apical horn. Dorsal and lateral bars may emerge from upper thorax as short radially disposed spines. Thorax has a weak shoulder proximally, at level at which spines emerge, remainder being variable in shape from evenly conical to campanulate. Distal margin typically flared with ragged termination. Simple circular pores increase gradually in size from cephalis to basal margin.

Remarks: Distinguished from C. cosma cosma by absence of thorns on the apical spine and the tendency towards a campanulate outline. In this latter respect this species resembles Clathrocycloma parcum Foreman which is distinguished by having a vertical tube (cephalopyle of Pessagno, 1969) rather than a vertical spine. Rare variants in which the vertical spine is missing (as in Nishimura's specimen) are included.

Occurrence: ODP Site 1121, Campbell Plateau, rare in RP4, common in RP5-6; DSDP Site 208, Lord Howe Rise, rare from RP4 to RP5.

Chris Hollis

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