Botryostrobus miralestensis (Campbell and Clark)

Dictyocephalus miralestensis Campbell and Clark, 1944, p.45, pl.6, figs.12-14

Botryostrobus miralestensis (Campbell and Clark), Nigrini, 1977, p.249, pl.1, fig.9 (with synonymy)

DESCRIPTION

Shell spindle-shaped with thick wall, surface rough with irregular longitudinal ridges. Intersegmental constrictions (other than collar and lumbar strictures) unevenly spaced and externally obscure, but internally pronounced; five to seven segments, fourth and fifth being widest. Cephalis small, hemispherical, with small irregular pores; vertical tube short, cylindrical, directed obliquely upward at about 45; no apical horn. Thorax and subsequent segments each bearing two to three transverse rows of large circular pores. Shell narrowing distally to generally well-developed poreless peristome; last segment cylindrical. Termination smooth (Nigrini, 1977).

DIMENSIONS

Based on 15 specimens. Total length 155-190 m; maximum breadth 60-90 m (usually 75-90 m) (Nigrini, 1977).

DISTINGUISHING CHARACTERS

See Botryostrobus aquilonaris

DISTRIBUTION

This species is found in both low and middle latitudes, but is rare in the latter. It is present in DSDP Site 594 (off New Zealand) material. Rare to few from the Cyrtocapsella tetrapera Zone to the Diartus petterssoni Zone.

PHYLOGENY

Precursor of Botryostrobus aquilonaris.

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