This is Mazon Monday post #236. What's your favorite Mazon Creek fossil? Tell us at email:[email protected].
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Cyathocarpus arborea is one of the rarer species of fern in the Mazon Creek deposit. It was originally named as Filicites arborescens by Ernst Freiedrich, Freiherr von Schlotheim in 1820. Schlotheim was a German paleontologist and pollitician who lived from 1764 to 1832. He created a very extensive collection of fossils, many of them Carboniferous plants. In 1804, he published descriptions and illustrations of some of his best specimens. Filicites arborescens was reclassified as Cyathocarpus by Frederick Ernest Weiss (1865-1953) in 1869.
Ernst Friedrich, Baron von Schlotheim.
C. arborea appears on page 101 in Jack Wittry's "A Comprehensive Guide to the Fossil Flora of Mazon Creek".
Cyathocarpus arborea (Sternberg) Mosbrugger, 1983, Pecopteris arborescens auct.
1820. Filicites arborescens Schlotheim: p. 404
1825. Pecopteris arborea Sternberg: p. 18
1834. Pecopteris arborescens Schlotheim; Brongniart: p. 310, pl. 102, figs. 1, 2; pl. 103, figs. 2, 3
1879-80. Pecopteris arborescens Schlotheim; Lesquereux: p. 230, pl. 41, figs. 6, 7
1899. Pecopteris ef. arborescens; White: p. 78, pl. 44, fig. 3
1924. Asterotheca arborescens Schlotheim; Kidston: p. 483, pl. 114, fig. 1
1924. Asterotheca cyathea (non Schlotheim); Kidston: pl. 115, fig. 1, (non text)
1951. Pecopteris arborescens Schlotheim; Corsin: p. 326, pls. 170-173
1958. Asterotheca arborescens Schlotheim; Langford: p. 159, fig. 269
1969. Pecopteris arborescens Schlotheim; Darrah: p. 130, pl. 11 fig. 1 (?)2; pl. 13, fig. 3; pl. 74, fig. 1; pl. 79, fig. 3DESCRIPTION: The penultimate pinnae (see Fig. 1) are linear-lanceolate and sharply taper to blunt lobes at their apices. The ultimate pinna is straight, of an equal width for its entire length, and terminates in a blunt lobe. The rachis is straight and heavy. The pinnules are alternate, closely placed, about twice as long as wide, about 5 mm or less in length, straight-sided, nearly rectangular in appearance, and free all the way to the pinna tip. They arise at a right angle or very slightly oblique to the rachis. The midvein is straight. The lateral veins are straight and simple or, very rarely, may divide once. The venation is often obscured by a villous coating. The sori have an asterothecoid appearance with 4 or 5 sporangia.
REMARKS: Cyathocarpus arborea is very rare. For nearly 200 years, this fossil form had the name arborescens, given by Schlotheim. It has since been ruled by the International Code of Botanical Nomenclature (ICBN) (Art. 13.1f) that all of Schlotheim's names predate the cutoff period for valid taxonomic names. The name arborescens is now considered a junior synonym to arborea.
George Langford used the name Asterotheca arborescens in his 1958 book "The Wilmington Coal Flota from a Pennsylvanian Deposit in Will County, Illinois". It can be found on page 159.
Asterotheca arborescens. Schlotheim
This species may be recognized by its pinnae which are long and very narrow, sides even and parallel to near the apex. The pinnules are close, 3/16 inch long and less, and half as wide. The veins do not fork, 4a.
Specimens
Langford specimen
Field Museum specimen PP58269. Collected by Jim and Sylvia Konecny in 1966. Donated to the Field Museum in 2017.
Field Museum PP16984
Field Museum PP43522
