Reynoldsia

Reynoldsia is an obsolete genus of flowering plants in the ivy family, Araliaceae. In 2003, Kew Gardens published a checklist for Araliaceae, in which eight species were recognized for "Reynoldsia": four from Samoa, two from Tahiti, one from the Marquesas, and one from Hawaii. In 2010, a phylogenetic comparison of DNA data showed that "Reynoldsia" was polyphyletic, consisting of two groups that are not each other's closest relatives. In a companion paper, three of the species were "sunk" into synonymy with others, reducing the number of species to five. All species that were formerly in "Reynoldsia" are now in "Polyscias" subgenus Tetraplasandra, a subgenus of 21 species indigenous to Malesia and Pacific islands.
"Reynoldsia" was a genus of shrubs to medium-sized trees, mostly of dry habitats, especially the leeward sides of tropical pacific islands. The leaves are imparipinnate, and alternate. The leaf margin is never completely entire, but varies from obscurely to patently dentate.
 considered "Reynoldsia" to be hard to distinguish from "Tetraplasandra", another defunct genus to which it was closely related. In general, "Reynoldsia" can be recognized by its toothed leaflets, greater number of ovary cells, and smaller number of stamens.
"Polyscias sandwicensis" (formerly "Reynoldsia sandwicensis") is cultivated, albeit rarely, in Hawaii. Instructions for its cultivation are available.
Species.
Eight species were listed by Frodin and Govaerts (2003) for "Reynoldsia". Lowry and Plunkett (2010) recognized only five of these, and placed them in "Polyscias" subgenus Tetraplasandra. The synonyms given below are the species recognized by Frodin and Govaerts (2003).
History.
The genus "Reynoldsia" was erected in 1854 by Asa Gray in his account of the botany of the United States Exploring Expedition (1838-1842). The genus was named for Jeremiah N. Reynolds, a plant collector in Chile in the early 19th century. Gray named two species: "Reynoldsia pleiosperma" from Samoa and "Reynoldsia sandwicensis" from Hawaii. John Hutchinson designated the latter as the type species for "Reynoldsia" in 1967. This is not recorded in Index Nominum Genericorum, where such information is usually found.
Berthold Carl Seemann named a Tahitian species, "Reynoldsia verrucosa", in 1864. In 1873, named another Tahitian species, "Reynoldsia tahitensis". Many authors, such as Forest B. H. Brown, did not accept "R. tahitensis" as a separate species from "R. verrucosa".
In 1925, Bénédict P.G. Hochreutiner named a second species from Samoa, "Reynoldsia lanutoensis". In 1935, a third species from Samoa, "Reynoldsia grayana" was named by Erling Christophersen. Christophersen suggested that some plants from a place called Tau might be a fourth species of "Reynoldsia" in Samoa. Also in 1935, "Reynoldsia marchionensis", a species from the Marquesas, was named by Forest B.H. Brown. The rare Samoan endemic, "Reynoldsia tauensis", was finally published as a separate species in 1968 by Albert C. Smith and Benjamin Clemens Stone.
Some sources state that there are two species of "Reynoldsia" in the Society Islands, and this error has been copied from one source to another. An examination of the references cited here shows that "R. marchionensis" is the only species name in "Reynoldsia" that was ever published for a plant from the Society Islands.
Earl Edward Sherff believed that there were eight species of "Reynoldsia" in Hawaii. In 1952, he published names for these, as well as descriptions and an identification key. Subsequent authors have regarded these names as merely regional variants or forms of "Reynoldsia sandwicensis".
In 2003, a checklist and nomenclator was published for Araliaceae. Eight species were recognized therein. The authors stated that "Reynoldsia" is "seen as biphyletic". The biphyly of "Reynoldsia" was confirmed in 2007, in a molecular phylogenetic study of what is now called "Polyscias" subgenus Tetraplasandra. It was confirmed again, in 2010, in a study of DNA sequences of selected genes in the pinnate genera of Araliaceae.
In an accompanying paper in Plant Diversity and Evolution, all of the pinnate Araliaceae were placed in the large genus "Polyscias", thus raising the number of species in that genus from about 100 to 159, not counting about 90 species that will be published in forthcoming papers. Six of the genera that were recognized in the 2003 checklist ("Arthrophyllum, Cuphocarpus, Gastonia, Reynoldsia, Munroidendron," and "Tetraplasandra") were subsumed into "Polyscias".
"Polyscias" was then divided into 11 subgenera (Polyscias, Grotefendia, Maralia, Arthrophyllum, Cuphocarpus, Tetraplasandra, Eupteron, Sciadopanax, Tieghemopanax, Indokingia, and Palmervandenbroekia) and 7 species ("Polyscias acuminata", "Polyscias macdowallii", "Polyscias mollis", "Polyscias murrayi", "Polyscias ledermannii", "Polyscias pentamera", and "Polyscias purpurea") were placed in "Polyscias" incertae sedis (not in any subgroup thereof). All of the species of the former "Reynoldsia" are now in "Polyscias" subgenus Tetraplasandra.
This subgenus consists of the four south Pacific species that were in "Reynoldsia", four of the six species that Philipson had placed in "Polyscias" section Eupteron, the two Malesian species that had been in "Gastonia", and a Hawaiian clade of 11 species. The Hawaiian clade consists of the sister species "Polyscias sandwicensis" (formerly "Reynoldsia sandwicensis") and "Polyscias racemosa" (formerly "Munroidendron racemosum"), as well as a monophyletic group of nine species that had been in "Tetraplasandra" as defined by in 1970.
When "Polyscias" was recircumscribed in 2010, the authors did not recognize all of the eight species that had been recognized in 2003. They placed "R. grayana" and "R. tauensis" into synonymy under "R. lanutoensis". They likewise subsumed "R. tahitiensis" into "R. verrucosa". The resulting five species were transferred to "Polyscias" as "P. lanutoensis", "P. pleiosperma", "P. marchionensis", "P. verrucosa", and "P. sandwicensis".
Sources.
Gregory M. Plunkett, Jun Wen, Porter P. Lowry II, Murray J. Henwood, Pedro Fiaschi, and Anthony D. Mitchell. accepted, undated. Araliaceae, pages ??. In: Klaus Kubitzki (editor); ?? (volume editor). "The Families and Genera of Vascular Plants" volume ??. Springer-Verlag: Berlin; Heidelberg, Germany. ISBN ??