Demorhethium lappaceum

Name

Demorhethium lappaceum

Rank

Species

Generic Name

[Genus] Demorhethium

Authors (Pub.)

Loeblich A. R., Jr. Wicander E. R.  

Publication

New Early Devonian (Late Gedinnian) microphytoplankton: Demorhethium lappaceum n. g., n. sp., from the Bois d'Arc Formation of Oklahoma, U.S.A. [1974/12]

Journal

Neues Jahrbuch für Geologie und Paläontologie Monatshefte

Annee/Jahrgang

1974

Issue

12

Page number

708

Year

1974

Fossil Status

vesicles

Stratigraphy

Lochkovian

Strat. comment

Bois d'Arc Formation

Location

W Clarita, Coal County, Oklahoma, USA

Paleoregion

Laurussia (Laurentia)

Data for Holotypus

Repository

University of California Los Angeles, Los Angeles, USA

Repository Number

Y. Tappan Loeblich Coll. ?

Num

fig. 2

Pub.

New Early Devonian (Late Gedinnian) microphytoplankton: Demorhethium lappaceum n. g., n. sp., from the Bois d'Arc Formation of Oklahoma, U.S.A. [1974/12]

Diagnosis

Vesicle spherical, subspherical to subangular in outline, with 5-7 short, broad, conical processes that taper little throughout their length, truncated distally and ringed with 4-5 small, hollow and flexible spinules, processes constricted proximally at their juncture with the vesicle; commonly the distal ends of the processes are invaginated through collapse; processes are hollow, but do not communicate with the vesicle; wall thin, about 0.5 μm in thickness, that of the vesicle ornamented by an assortment of tiny simple and capitale bacules and clavae less than 1 μm in length which commonly arise from a series of anastomosing elevated ridges separated by open spaces below and between adjacent ridges, giving a spongy appearance to the vesicle surface and which may become detached to leave the surface with only scattered simple spinules; process wall commonly striated in proximal portion and ornamented with small warts at the junction with the vesicle, remainder of process psilate with rare tiny warts scattered over the main process and terminal spinules. No pylome or excystment mechanism observed other than a simple rupture of the vesicle wall on a single specimen. Diameter of vesicle ranges from 13-17 μm and overall diameter from 23-37 μm.