NAME Sporocarpon majus
AGE Early-Middle Pennsylvanian.   AGE span: 311.7...307.2 mya
K&J CLASSIFICATION (2000) Ascomycetes, Eurotiales.
FIGURE(S)
Image of
Pl.29fig.12.jpg
FIGURE REFERENCE Baxter RW. 1960. Sporocarpon and allied genera from the American Pennsylvanian; Phytomorphology, v. 10, p. 19-25.
SPECIES, AUTHORITY S. majus (Baxter) Kalgutkar & Jansonius 2000
LOCATION Chanute Shale of Kansas City. Missouri, USA.
ORIG DESCRIPTION* Spherical structures up to 1800 µm in diameter with an average diameter of approximately 1200 µm; containing a central spherical cavity up to 900 µm in diameter with an average for the majority of the specimens of 600 µm. The wall consists of a single layer of radially elongated club-shaped cells 300-450 µm in length and with an average width of 55 µm when measured near the outer surface of the sphere; tapering slightly to the width of 40 µm at their inner ends. Cells compactly arranged. Outer surface of sphere smooth. No internal membranes or loose cells observed in the central cavity.
COMMENTS* Hutchinsons's (1955) description of Dubiocarpon elegans mentions septate cells resembling fungal hyphae inside the sphere cavity while one specimen of Mycocarpon (Sporocarpon) pachydermum is described as having hyphae running between the cells and out into the surrounding matrix. There thus seems to be a gradually increasing weight of evidence that Dubiocarpon as well as Mycocarpon may be some sort of fungal structure. The weight of his evidence is based on Sporocarpon compactum, Sporocarpon elegans and Sporocarpon tubulatum which Hutchinson (1955) included in the genus Dubiocarpon. As Hutchinson's name implies, these forms constitute an enigmatic group and may possibly not even be plants although the structure of Dubiocarpon majus and its close association with aseptate hyphae make it more comparable to the fungi than any other group. However, when one considers the other species of Sporocarpon, S. cellulosum, and S. asteroides, there is absolutely no justification for viewing them as anything but thallophytic plants and even McLean [1922] was unable to show anything in his illustrations remotely resembling tubular wall structure. Our Sporocarpon spinatum also is clearly composed of parenchymatous plant cells and belongs with the above species as treated by Hutchinson (1955). The specific name recognizes the greater size, more than twice that of the previously known species.
PUBLICATION REFERENCE Baxter RW. 1960. Sporocarpon and allied genera from the American Pennsylvanian; Phytomorphology, v. 10, p. 19-25.
K&J REMARKS
TYPE Dubiocarpon majus Baxter 1960, p. 22, fig. 8 (lectotype selected by Kalgutkar & Jansonius 2000 ).
ALL NAMES (Including synonyms) Dubiocarpon majus Baxter 1960, p. 22, fig. 8.; Sporocarpon majus
SERIAL NUMBER 1612
PUBLIC COMMENTS
 *For source, see Publication Reference.