Fernald's S. ozarkanus
by Bob Harms  email-here

In 1933 (Rhodora 35) M. L. Fernald declared a new species, Sporobolus ozarkanus, based in part on its glabrous florets (p. 109):

S. ozarkanus, in its long spikelets, narrow lemma and strongly ciliate sheath-orifices is like typical S. vaginaeflorus; but its quite glabrous lemmas and strongly pubescent leaves quickly set it apart.

The type specimen, with glabrous florets, is E. J. Palmer 3133 (GH).

L. H. Shinners' 1954 revision

In 1954 (Rhodora 56) L. H. Shinners revised the Sporobolus vaginiflorus complex by declaring varietal status for S. neglectus: as S. vaginiflorus var. neglectus (Nash) Shinners, comb. nov. S. neglectus Nash; and S. ozarkanus: as S. vaginiflorus var. ozarkanus (Fernald) Shinners, comb. nov. S. ozarkanus Fernald. Shinners' total justification for the latter consisted of two lines with no discussion (p. 29):

To complete the roster, one extra–limital variety may be added: S. vaginiflorus var. ozarkanus (Fernald) Shinners, comb. nov. S. ozarkanus Fernald, Rhodora 35: 109. 1933.

Shinners had thus created two varieties of S. vaginiflorus with glabrous florets! And no key to distinguish them.

J.A. Steyermark & C. L. Kucera stress glabrous lemmas

In 1961 (Rhodora 63) J.A. Steyermark & C. L. Kucera countered by placing S. ozarkanus as a variety of S. neglectus: S. neglectus (Nash) var. ozarkanus (Fern.) Steyermark & Kucera) based on the glabrous and short, pointed lemmas. They argue (p. 25) that this "together with the relatively less elongated apex of the palea apparently relate S. ozarkanus more closely to S. neglectus than to S. vaginiflorus."

R. L. Riggins 1969 restores Sporobolus ozarkanus (Fernald)

In her data–rich thesis (Iowa State University, 1969) R. L. Riggins presents a detailed and compelling case for recognizing three taxa in the Sporobolus vaginiflorus complex: S. neglectus Nash, S. vaginiflorus (Torr.) Wood, and S. ozarkanus (Fernald). Most significantly she documents forms of S. ozarkanus with pubescent lemmas, complicating the use of lemma vestiture as a differentia.

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