Caladenia lowanensis

Wimmera spider orchid
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Orchidaceae
Subfamily: Orchidoideae
Tribe: Diurideae
Genus: Caladenia
Species:
C. lowanensis
Binomial name
Caladenia lowanensis
Synonyms[1]

Arachnorchis lowanensis (G.W.Carr) D.L.Jones & M.A.Clem.

Caladenia lowanensis, commonly known as Wimmera spider orchid, is a plant in the orchid family Orchidaceae and is endemic to Victoria, Australia. It is a ground orchid with a single leaf and a single cream-coloured flower with red lines and blotches. The total population of this orchid was estimated in 2010 to be only about 700 plants but most are protected in reserves.

Description

Caladenia lowanensis is a terrestrial, perennial, deciduous, herb with a spherical underground tuber. It has a single leaf, 70–120 mm (3–5 in) long and 8–12 mm (0.3–0.5 in) wide. A single flower 30–40 mm (1–2 in) wide is borne on a spike 120–250 mm (5–10 in) tall. The flowers are cream-coloured with red streaks and blotches. The sepals have flattened, club-like, dark red glandular tips 5–8 mm (0.2–0.3 in) long. The dorsal sepal is erect, 25–35 mm (0.98–1.4 in) long and 2.3 mm (0.09 in) wide. The lateral sepals are 25–35 mm (0.98–1.4 in) long, 3–4 mm (0.12–0.16 in) wide and spread widely, sometimes curved downwards. The petals are 20–25 mm (0.8–1 in) long, about 2 mm (0.08 in) wide and arranged like the lateral sepals. The labellum is egg-shaped, 10–14 mm (0.4–0.6 in) long, 6–8 mm (0.2–0.3 in) wide and pale yellowish with red streaks and a red tip which is curled under. The sides of the labellum have linear teeth up to 2 mm (0.08 in) long and there are four or six well-spaced rows of shiny red calli along its mid-line but not extending to the tip. Flowering occurs in September and October.[2][3][4]

Taxonomy and naming

Caladenia lowanensis was first formally described in 1991 by Geoffrey Carr from a specimen collected near Kiata and the description was published in Indigenous Flora and Fauna Association Miscellaneous Paper 1.[1] The specific epithet (lowanensis) is derived from the Lowan district of Victoria with the Latin suffix -ensis meaning "of" or "from"[5] referring to the distribution of this orchid species.[6]

Distribution and habitat

The Wimmera spider orchid grows in sparse woodland near Kiata, in and near the Little Desert National Park.[2][3][4]

Conservation

Caladenia lowanensis is listed as "endangered" under the Victorian Flora and Fauna Guarantee Act 1988 and under the Australian Government Environment Protection and Biodiversity Conservation Act 1999. In 2010 the known population of this species was 700 plants in five populations but about 90% of these were protected in reserves. The main threats to the species are rubbish dumping, trampling, weed invasion and grazing by rabbits (Oryctolagus cuniculus).[4][7]

References

  1. ^ a b c "Caladenia lowanensis". APNI. Retrieved 18 February 2017.
  2. ^ a b Jeanes, Jeffrey. "Caladenia lowanensis". Royal Botanic Gardens Victoria: Vicflora. Retrieved 18 February 2017.
  3. ^ a b Jones, David L. (2006). A complete guide to native orchids of Australia including the island territories. Frenchs Forest, N.S.W.: New Holland. pp. 72–73. ISBN 1877069124.
  4. ^ a b c "Conservation Advice Caladenia lowanensis (Wimmera spider-orchid)" (PDF). Australian Government Department of the Environment. Retrieved 18 February 2017.
  5. ^ Brown, Roland Wilbur (1956). The Composition of Scientific Words. Washington, D.C.: Smithsonian Institution Press. p. 38.
  6. ^ Clifford, Harold T.; Bostock, Peter D. (2007). Etymological dictionary of grasses. Berlin: Springer. p. 175. ISBN 9783540384328.
  7. ^ "Action statement: Twelve threatened Caladenia species" (PDF). Government of Victoria, Department of Sustainability and Environment. Retrieved 18 February 2017.