Hairs on Scolecopteris sporangia
deutsche Version

Hairs on sporangia are a typical feature of 5 of the 15 Scolecopteris species distinguished by Millay [1]. (
Scolecopteris is the name of the foliage of Palaeozoic tree ferns which are better known under the name of their stems, Psaronius.) Hairs are assumed to be completely absent on the sporangia of the “maggot fern” from Döhlen basin, Sc. elegans. In view of the several pieces of evidence lately accumulated which indicate the presence of more than one Scolecopteris species at the type locality of Sc. elegans it is not surprising that, among the hundreds of chert samples cut and polished in the latter years, hairy sporangia have been discovered in two of them (Figs.1,2).
Scolecopteris sporangia with two hairs eachHairy sporangia of Scolecopteris
Fig.1: Cross-section of a synangium composed of 4 hairy sporangia; non-identified Scolecopteris species from the type locality of Sc. elegans, Döhlen basin.

Fig.2 (far left): Sporangium tips with two hairs each (cut off on one of them); non-identified Scolecopteris species from the type locality of Sc. elegans, Döhlen basin.

It is not obvious how to interpret these observations. The hairs could be an incidentally re-activated old feature inherited from hairy ancestors but normally suppressed in Sc. elegans, or else they could indicate the presence of other species. Anyway it is worth while trying to relate the finds to the 5 hairy species: Sc. minor, Sc. latifolia, Sc. mamayi, Sc. monothrix, Sc. vallumii.
The synangium cross-section in Fig.1 is compatible with Sc. minor but not with the others: Sc. latifolia looks quite different according to a picture in [1], the sporangia of Sc. mamayi have the hairs only at their tips, those of  Sc. monothrix have only one very long hair each, and also the hairs of  Sc. vallumii are much longer.
The sporangia with two hairs each near the tip as seen in clear chalcedony in Fig.2 do not seem to fit onto any of the hairy species: Pinnules with forked veins have been found near the sporangia, most probably being related to them. This excludes Sc. mamayi, which is said to have non-forked veins. Again, Sc. monothrix and Sc. vallumii can be excluded because of the length of their hairs.
The observation of two types of hairy sporangia at the type locality of Scolecopteris elegans adds to the evidence for the presence of other species.  (See also the contribution on veining patterns.)

Specimens: Chert from the type locality of  Scolecopteris elegans, Lower Permian, Döhlen Basin;   
own collection; Fig.1: Bu13/19.1, (1998);   Fig.2: Bu7/140.2, (2003),  raw sample obtained from  Gert Müller.

H.-J. Weiss       2011 

[1]  M.A. Millay: Study of paleozoic marattialeans. A monograph of the American species of Scolecopteris, Palaeontographica B169(1979), 1-69
Scolecopteris pinnule cross-section, Sardinia Permian Chert News 3

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