Catalog - Globorotalia (Globorotalia) tumida lata

This page provides data from the catalog of type descriptions. The catalog is sorted alphabetically. Use the current identification link to go back to the main database.

Globorotalia (Globorotalia) tumida lata

Citation: Globorotalia (Globorotalia) tumida lata Brönnimann & Resig 1971

Type age (chronostrat): Pleistocene

Type locality: SW Pacific, Eauripik Ridge, Hole 62.1 2 Core 4, Sec.5, 16-18cm, Zone N.22

Type repository: Washington; USNM

he test is small- to medium-sized for the species,strongly tumid and heavy-keeled. The keel of the ultimate chamber in umbilical view is about 50 microns thick. In spiral and umbilical view, its outline is broadly oval. The spiral side is strongly convex and the umbilical side almost flat, excepting for the final chamber which is slightly convex. The trochospire of more than 12 chambers is very tightly coiled in the early portion and development of secondary calcite layers masks the sutures between the first chambers.
The last whorl consists of five chambers which rapidly increase in size. The ultimate chamber is about 525 microns wide and almost equals in its largest diameter the width of the test. Its maximum length is about 350 microns. The spiral sutures of the last whorl are slightly depressed and the intercameral sutures between the three last chambers of the final whorl are deeply incised near their axial portion and are virtually even with the chamber surfaces peripherally. The intercameral sutures are more strongly curved on the spiral side and almost radial on the umbilical side, where they are strongly incised. The umbilical side shows five chambers, rapidly increasing in size, separated by a narrow but deep umbilicus. The umbilical- extra umbilical aperture is a low, elongate opening covered by a strongly pustulate, thick plate-like lip with a denticulate margin 125 microns in length and 100 microns maximum width. The ventral portions of the early chambers and the keel of the first and second chambers of the ultimate whorl are strongly pustulate.
The heavy walls are calcareous, perforate and the spiral surface of the chambers pustulate, with the exception of the ultimate and penultimate chambers which are less pustulate on the spiral side.

The holotype is from Hole 62.1, Core 4, Section 3, 15-17 centimeters, Zone N. 22. The specimen coils to the left. It is illustrated on Plate 29, Figure 3. Its maximum width is 550 microns and its maximum length 115 microns. Its axial height is about 360 microns.

Globorotalia (Globorotalia) tumida lata, n. subsp., differs by its tangentially wide end-chamber from Globorotalia tumida tumida (Brady), 1877, and by its tumid,heavy-keeled test from the representatives of the cultrata group. The paratype, Plate 49, Figures 4 and 5,has a maximum diameter of 600 microns. The specimen coils to the right. It possesses a lip with strong,pointed, elongate pustules which extend perpendicularly from its margin; also the umbilical pustules are strong and pointed. The maximum diameters ofparatypes range from about 620 to 800 microns.

References:

Brönnimann, P. & Resig, J. (1971). A Neogene globigerinacean biochronologic time-scale of the southwestern Pacific. Initial Reports of the Deep Sea Drilling Project. 7(2): 1235-1469. gs O

CATALOG OF ORIGINAL DESCRIPTIONS: Globorotalia (Globorotalia) tumida lata Brönnimann & Resig 1971

Globorotalia (Globorotalia) tumida lata

References:

Add Comment

Comments