| Home> Miocene>

List species

Lophocyrtis pegetrum (Sanfilippo and Riedel, 1970)

Description - Add description

Lophocyrtis ( Cyclampterium ) pegetrum (Plate II, 3-5 )

Remarks: Lophocyrtis ( Cyclampterium ) pegetrum is distinguished from its ancestor L. (C.) milowi by the median thoracic length being greater than 90 ttm and, when feet are present, by these being solid rather than latticed. From its descendant L. (C.) leptetrum it differs by its shorter (90-125/~m vs. 150-165 ~m) thorax and coarser abdominal meshes. L. (C.) pegetrum differs from mid latitude morphotypes of L. (Paralampterium) dumitricai by its larger thorax and from L. (P.) ? galenum by having a longer abdomen without a differentiated termination and by not having the feet ridged and pored.

New observations (on 30 specimens from DSDP Site 73 Cores 13, 14; Site 77B Core 34; Site 289 Cores 64, 69, 71, 75; Site 315A Core 9; Site 366 Core 5 and Site 515B Cores 25, 30, 36): total length 215-620 µm; length of thorax 75-155 µm, width 125-215 µm, number of pores around the circumference 20-30; length of abdomen 85-340 µm, width 160-300 µm, number of pores around the circumference 6-15. No horn; some specimens have a thickened cap over the cephalis.
L. (C.) pegetrum is rare to moderately abundant from its evolutionary transition from L. (C.) milowi in the early Dorcadospyris ateuchus Zone to the middle of the Cyrtocapsella tetrapera Zone, where it evolves into L. ( C. ) leptetrum (latest Oligocene to Early Miocene).











Discussion / Comments


Web links