| Home> Miocene>
 

List species

Podocyrtis (Podocyrtopsis) apeza Sanfilippo and Riedel, 1992

Description - Add description

Podocyrtis (Podocyrtopsis) apeza n. sp. Sanfilippo and Riedel 1992 p. 14, Pl, 3, fig 13-15

Type material: Holotype (pi. 3, fig. 15) from DSDP Site 162, Core 6, in the Late Eocene Cryptocarpium azyx Zone (formerly "Carpocanistrum" azyx Zone).

Cephalis with many pores, and an apical horn variable in length, bladed to conical. Thorax conical to inflated, constituting the bulk of the skeletal volume, with circular pores uniform in size and regular in arrangement. Lumbar stricture indistinct externally. Abdomen approximately cylindrical, sometimes inflated, with abdominal pores less regular in size and arrangement than those of the thorax, except in early forms where they are separated by longitudinal ribs. Some late forms, which have a thin abdominal wall, terminate in an irregular poreless peristome.

Measurements:
(based on 50 specimens from DSDP Site 29. Core 10; Site 29B, Core 8; Site 42. Cores 6, 8; Site 149, Cores 32. 33, 35, 36; Site 162, Cores 6. 9; Site 219, Core 19). Length of cephalothorax 120-185μm (commonly around 145μm), total length (excluding horn) l80-250μm. Maximum width 110-I80μm (commonly around 135μm).

Etymology:
The name is the feminine form of the Greek adjective apezos meaning footless.

Distribution:
Podocyrtis (Podocyrtopsis) apeza ranges from the Podocyrtis mitra Zone (Middle Eocene) into the Cryptocarpium azyx Zone (Late Eocene). It is rare to moderately abundant (0.1-5%) in all of the low latitude assemblages of appropriate age used in this study (see also Distribution of subgenus).

Distinguishing characters:
In addition to the distinctions mentioned in the generic definition, it is useful to note that this form differs from large, delicate, Oligocene and early Miocene relatives of Theocyrtis tuberosa and T. annosa by the latter having a superficially puckered collar region and commonly more than one apical thorn.

Picture: 15, holotype, 162-7-6, 128-130 Cs.3 X32/0. Magnification x235

Sanfilippo and Riedel 1992


Description

 

Images

 

Synonyms

 

References

 

Distribution

 

Discussion / Comments

 

Web links