Caladenia montana
G.W.CarrFlowering plant 10–30 cm tall. Leaf 6–12 cm long, 5–12 mm wide Flowers 1 or 2, with a strong burnt-plastic scent; perianth segments 2–4(–6) cm long, greenish cream to yellowish, sometimes with red median stripe and/or reddish suffusions; sepals 2–4 mm wide at base, tapered to filiform, narrowly clubbed tails, club 5–15 mm long, with dark-coloured, sessile glands which are mostly tightly packed and contiguous; lateral sepals divergent, spreading to deflexed; petals spreading to deflexed, shorter than sepals, flattened at base, tapered to long acuminate apex, sometimes with small, glandular, clubbed section shortly below tip. Labellum curved forward with apex recurved and lateral lobes curved upwards, lamina ovate or broadly ovate-lanceolate, obscurely 3-lobed, 10–13 mm long and 7–9 mm wide (when flattened), glossy red distally and along centre to the pale yellowish-green base; lateral lobes entire around curved base, then with marginal calli linear to triangular, mostly to 1 mm long (sometimes much smaller, rarely to 2.3 mm), diminishing in size towards entire or slightly irregular mid-lobe; lamina calli in 4 or 6 rows, not reaching or shortly exceeding the bend, linear or foot-shaped, to 1.5 mm long at base of lamina, decreasing in size towards apex. Flowers Sep.–Jan.
NIS, EGL, EGU, HSF, HNF, MonT, VAlp. Also NSW, ACT. Localised to higher montane areas of eastern Victoria where it grows among shrubs on slopes and ridges in woodland on well-drained soils.
Caladenia montana is similar to, and could be confused with, a few other eastern species; see C. fitzgeraldii, C. peisleyi and C. australis. A form, rarely collected, from the Buchan-Orbost area differs from typical C. montana in having larger perianth segments (lateral sepals 4–6 cm long), more numerous (ca. 15 or more pairs) and longer linear teeth on the lateral lobes of the labellum. Should further collections of this form be made and should these distinctions appear to be diagnostic, it may warrant formal recognition. Flowers of both this form and typical C. montana are noted to emit an odour reminiscent of burning plastic in warm weather.
When the marginal calli of the labellum are particularly small and blunt, C. montana resembles C. clavigera, but differs from that species in having thicker and longer clubs, and a broader labellum with narrower lamina calli. Caladenia montana is known to hybridize with C. clavigera.
Caladenia osmera was formerly treated as a separate species, but has been shown by Kosky (2021) to be indistinguishable from C. montana.
Entwisle, T.J. (1994). Orchidaceae. In: Walsh, N.G.; Entwisle, T.J., Flora of Victoria Vol. 2, Ferns and Allied Plants, Conifers and Monocotyledons, pp. 740–901. Inkata Press, Melbourne.
Kosky, W. (2021). East Gippsland’s Clubbed Spider Caladenia (Orchidaceae: Caladeniinae). Muelleria 40: 3–30.
