The genus
Chloropyron was first
described by the German-American
polymath Hans Hermann Behr, an immigrant to
San Francisco, in 1855. The first species to be described was
Chloropyron maritimum.
Thomas Nuttall first described it in the genus
Cordylanthus, but this was only in an unpublished manuscript, and was thus not a valid taxonomic name.
George Bentham, however, revived the name in his 1846 entry on these plants in
Augustin Pyramus de Candolle's
Prodromus Systematis Naturalis Regni Vegetabilis. In three different 1891 publications three different botanical
taxonomists, the American
Edward Lee Greene, the Austrian
Richard Wettstein and the German
Otto Kuntze, had all pointed out that Bentham's 1836 name,
Adenostegia, had
priority, and all of the
Cordylanthus species were transferred to that name. Wettstein, following Gray's
Flora of North America, continued to recognise Gray's
Hemistegia group, ranking the group at the level of
section. He recognised 3 species of
Adenostegia, and split these three into two unranked subgroups, with
A. kingii and
A. maritima in group
A, having four developed
stamens in their flowers, and
A. mollis as the single species in group
B, having only two developed stamens. In 1911 the Californian botanist
Willis Linn Jepson raised the section
Hemistegia up to the level of
subgenus. Although the ICBN was accepted throughout the world, an exception was in the United States where a number of botanists rejected the new rules, and as such, when a new species in the group was added by the Californian botanist
Roxana Stinchfield Ferris in her 1918
monograph on the genus, she ignored the modern rules of nomenclature and named her new species
Adenostegia palmata. This was promptly rectified by the Harvard University botanist
James Francis Macbride the following year. In any case, Ferris also ignored Jepson's classification of
Hemistegia as a subgenus, maintaining Wettstein's system of sections, moved
Adenostegia kingii out of the group, and, oddly considering her upholding of Bentham's priority, renames the subgenus
Hemistegia to
Chloropyron. She recognised four species in this section, the earlier-mentioned
Adenostegia palmata, the two long-standing species
A. maritima and
A. mollis, and also moved Gray's
Cordylanthus canescens to the section. In 1951
Francis W. Pennell recognised six species in the group. The botanist
Herbert Louis Mason reduced this to three species in his 1957 book
A Flora of the Marshes of California. In 1950
Chloropyron tecopense was described (as
Cordylanthus tecopensis) by
Philip Alexander Munz and
John Christian Roos. In 1973 the botanists
Tsan-iang Chuang and
Lawrence R. Heckard, excluding this new species, also recognised three species from Pennell's six, but used a completely different
circumscription, so that Mason's taxa are not clearly synonymous with their species. ==Description==