Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-24T05:27:02.915Z Has data issue: false hasContentIssue false

Color patterns in Mississippian (Chesterian) blastoids

Published online by Cambridge University Press:  20 May 2016

Harold H. Beaver
Affiliation:
Department of Geology, Baylor University, Waco, Texas 76798
Alexander J. Fabian
Affiliation:
7016 Jackman Rd., Temperance, Michigan 48182

Abstract

Ninety-one specimens of Pentremites Say from the Mississippian Chesterian display color patterns. The darker color patterns represent a thin veneer of pigmented calcite which is barely visible on a polished surface or thin section, but which can be removed with dilute hydrochloric acid. Preservation appears to be best in specimens from shallow marine clays and shales. The patterns represent four color patterns, each consisting of different shades of calcite, and ranging in color from tan to black. Color patterns generally, but not always, cross growth lines. Type 1 has arched chevron patterns on the deltoids, horizontal lines on the radials, and triangular bands on the basals. Type 2 has darkened deltoids or concave chevrons on the deltoids and darkened areas concentric to the radials, and sometimes alternating light and dark bands conforming to growth lines on the radials. Type 3 has sloping lines crossing the radials, concave chevrons on the deltoids, and darkened areas on the lower radials, concentric to the ambulacra and on the basals. Type 4 has dark dots concentric to the lower ambulacra, arched chevrons on the deltoids and transverse lines abutting the radials and on the basals. The color patterns are original and may have been exposed on the outside of the integument.

Type
Research Article
Copyright
Copyright © The Paleontological Society 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bather, F. A. 1893. The Crinoidea of Gotland. Pt. I. The Crinoidea Inadunata. Kongllich Svenske Vetenskapssakademiens-Akademiens Handlingar: 25(2), 151 p.Google Scholar
Blumer, M. 1965. Organic pigments: their long-term fate. Science, 149(3685):722726.Google Scholar
Foerste, A. F. 1930. The color patterns of fossil Cephalopods and Brachiopods, with notes on Gastropods and Pelecypods. Contributions of the Museum of Paleontology, III (6) University of Michigan Press:109150.Google Scholar
Hoare, R. D. 1978. Annotated bibliography on preservation of color patterns on invertebrate fossils. The Compass of Sigma Gamma Epsilon, 55(3):3959.Google Scholar
Hollingworth, N. T. J., and Barker, M. J. 1991. Colour pattern preservation in the fossil record: taphonomy and diagenetic significance, p. 105119: In Donovan, S. K. (ed.), The Processes of Fossilization. Columbia University Press, New York.Google Scholar
Meyer, D. L., and Macurda, D. B. 1980. Ecology and distribution of the shallow-water crinoids of Palau and Guam. Micronesica, 16(1):5999.Google Scholar
Reimann, I. G. 1961. A Color-marked Devonian Blastoid. Oklahoma Geology Notes: 21(5):153157.Google Scholar
Sprinkle, J., and Gutschick, R. C. 1967. Costatoblastus, a channel fill Blastoid from the Sappington Formation of Montana. Journal of Paleontology, 41(2):385402.Google Scholar
Sprinkle, J. 1973. Morphology and Evolution of Blastozoan Echinoderms, Special Publication, The Museum of Comparative Zoology, Harvard University, Cambridge, 283 p.Google Scholar