Drosera Peltata - Taxonomy

Taxonomy

Drosera peltata was first described by Carl Peter Thunberg in 1797. Due to its large range and varied habit, D. peltata has accumulated a number of synonyms and infraspecific taxa, including varieties and subspecies. Most subspecies have been reduced to synonymy, but the two taxa that are still considered valid are D. peltata subsp. peltata, which is an autonym, and D. peltata subsp. auriculata, which was originally named by James Backhouse and formally described by Jules Émile Planchon in 1848 as D. auriculata and later reduced to a subspecies of D. peltata by Barry John Conn in 1981. Subspecies auriculata is still considered a valid and separate species by some authorities. The major difference between the subspecies involve seed shape and sepal pubescence. D. peltata subsp. peltata has ovate seeds and the sepals are hairy or pubescent, whereas D. peltata subsp. auriculata has linear seeds and glabrous sepals.

Although demoted to synonyms of D. peltata by Marchant in 1982, the formerly recognised species Drosera foliosa and Drosera gracilis are again treated as separate species by the Tasmanian Herbarium and the Australian Plant Name Index.

Drosera foliosa differs from the nominal form of D. peltata in having a well-defined basal rosette of large, light green lunate leaves, and multi-branched shorter stems. By contrast the nominal form of D. peltata has a less prominent basal rosette, and a single stem. It is mostly restricted to grasslands, herbfields and open woodland with grassy understorey.

Drosera gracilis is similar to the nominal form of D. peltata but smaller and with distinctly red stems and leaves. In Tasmania it is restricted to wet peaty areas, and unlike the winter and spring growers D. peltata and D. foliosa, it grows in late spring and late into the summer.