Morphological evaluation of the Drosera peltata complex (Droseraceae)
Robert Gibson, Barry J. Conn and Jeremy J. Bruhl
Australian Systematic Botany, 2012, 25, 49–80
http://dx.doi.org/10.1071/SB11030
Drosera lunata Buch.-Ham ex DC. Prodromus Systematis
Naturalis Regni Vegetabilis 1: 319 (1824);
Tuberous herb, usually olive-green; tuber ovoid, up to 9mm
diameter by 5mm tall; surface white to red, often in a papery
sheath; vertical stolon 2–6 cm long. Stem erect, usually simple,
sometimes shortly branched, 9–50 cm long, glabrous. Leaves,
often in a flat basal rosette and cauline; basal leaves 3–27, the
lamina ovate to elliptic, 1.5–5mm long by 3–7mm wide on a
linear petiole 4–14mm long, by up to 0.8mm wide; cauline
leaves alternate, the lamina crescentic, 0.7–3mm long by
1–4.5mm wide, with acute angles, on petiole 1–16mm long.
Inflorescence a 1-sided raceme 1–10-flowered; peduncle
usually 0.5–3 cm long; pedicels 1–12mm long. Sepals ovate,
elliptic, rhombic or ovate, 1.4–4.2mm long by 0.6–1.8mmwide,
glabrous with the margin entire to serrulate, or denticulate, to
partially to fully fimbriate with hairs up to 0.6mm long. Petals
obovate to cuneate, 1–6mm long by 1–3.2mm wide, white or
rarely pink. Styles 3, 0.4–1mm long, divided into a total of
~15–30 cylindrical segments. Seeds 0.3–0.6mm long by
0.3mm maximum diameter, ovoid with a shallowly reticulated
surface. Flowering throughout the year.
Habitat
This species occurs over a great altitudinal range, from sea
level in subtropical locations, to elevations of at least 3600m
altitude in tropical mountains (Hara 1966; Balakrishnan 1981;
Zhang 1982; Grierson and Long 1984; Naithani 1984; Larsen
1987; Amaratunga 1988); with one herbarium specimen
(R. Strachey s.n., anno 1867, K), possibly collected from
around 6000-m altitude at Jagersar, Uttarakhand, in the Indian
Himalayas.
Notes
This morphologically variable species can be a short, self-supporting
plant (often with a well developed basal rosette) or
can form slender plants up to 70 cm tall that are supported by
surrounding plants. This species can grow any time of year
when soil moisture conditions are optimum for growth.
Bracteole shape and margin and sepal margin are highly
variable, with the latter varying from entire to denticulate to
partially or fully fimbriate. Plants have been collected in flower
in every month of the year across the range. Unlike most
tuberous Drosera species, plants of D. lunata often grow in
summer and flower in autumn, at least partly in response to the
recurring wet season.