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Dicommopalla macadamii
Dicommopalla macadamii Loebl. Phycologia, 9(1): 39. 28 May 1970
- Name
- Dicommopalla macadamii
- Rank
- Species
- Generic Name
- [Genus] Dicommopalla
- Authors (Pub.)
- Loeblich A. R., Jr.
- Publication
- Dicommopalla, a new acritarch genus from the Dillsboro Formation (Upper Ordovician) of Indiana, U.S.A. [1970/5]
- Journal
- Phycologia
- Volume
- 9
- Issue
- 1
- Page number
- 39
- Year
- 1970
- Parent Taxon
- [Genus] Dicommopalla
- Fossil Status
- vesicles
- Stratigraphy
- Upper Ordovician
- Strat. comment
- Dillsboro Formation
- Location
- Road cut on U.S. Highway 421 in N.W. 1/4, Sec. 24, T. 4 N., R. 10E., Jefferson County, Indiana, USA
- Paleoregion
- Laurentia
Data for Holotypus
- Repository
- University of California Los Angeles, Los Angeles, USA
- Repository Number
- 69-76(3) 16.2-107.6
- Diagnosis
- Spherical to subspherical body, commonly folded and distorted into various shapes, margins ragged and irregular; apparently doublewalled with a thin outer covering showing on the ragged margins of the central body as a "keel" that is less than 1 p. to 6.5 µm in width, commonly seen detached at the margins in broken specimens; no processes; wall thin, about 1 µm thick; the wall sculpturing appears irregularly reticulate in the light microscope at X 1,000, but in the scanning electron microscope at magnifications of X 10,000 the wall sculpture is seen to consist of irregular ridges without any regular pattern; at magnifications of X 15,000 the larger irregular ridges are sculptured (microrugulate) into small ridges having a width of about 700 A; this sculpturing seems to be on the inner wall layer, because broken specimens that expose the inner wall surface appear rugulate in the light microscope; excystment by a rounded pylome, the aperture ranging from 6.5-16 µm in diameter, surrounded by an elevated smoothly finished rim; double pylomes occur on some specimens, and all specimens observed had one (or two) pylomes; maximum diameter ranges from 58-100 µ.
