Caladenia flava subsp. maculata

Taxonomy

• Kingdom: Plantae
• Clade: Tracheophytes → Angiosperms → Monocots → Asparagales → Orchidaceae
• Genus: Caladenia R.Br.
• Species: Caladenia flava Endl.
• Subspecies: Caladenia flava subsp. maculata (R.S.Rogers) Hopper & A.P.Br.

The subspecies was originally described as Caladenia maculata R.S.Rogers and later reduced to a subspecies of C. flava by Hopper & A.P. Brown in 2001. The epithet maculata derives from Latin, meaning “spotted,” referring to the characteristic reddish‑brown spots on the labellum and sometimes on the dorsal sepal.

Description

• Growth form: Terrestrial, perennial, deciduous herb arising from an underground tuber.
• Leaf: Single, erect, linear to lanceolate leaf, 60–150 mm long and 5–10 mm wide, green with occasional reddish blotches.
• Inflorescence: A raceme bearing up to three flowers, each 20–40 mm wide.
• Flower morphology:
  • Sepals and petals: Bright to pale lemon‑yellow; dorsal sepal erect, lateral sepals spreading slightly downwards.
  • Labellum (lip): Yellow with distinctive reddish‑brown to dark brown spots and blotches; the labellum is three‑lobed, with marginal teeth and a central callus consisting of fine ridges.
  • Column: Fused reproductive structure typical of Caladenia, with a short stigma and anther cap.
• Flowering period: Primarily from August to October, depending on regional climatic conditions.

Distribution and Habitat

• Geographic range: Endemic to the south‑west of Western Australia. Recorded from the Avon Wheatbelt, Geraldton Sandplains, Jarrah Forest, Swan Coastal Plain, and Warren biogeographic regions.
• Habitat: Occupies a variety of habitats including sandy heaths, shrublands, and open woodlands, often on well‑drained soils. It is frequently associated with Eucalyptus and Banksia communities and may be found in areas that experience a Mediterranean climate with wet winters and dry summers.

Ecology

• Pollination: Like many Caladenia species, it is thought to be pollinated by native insects, particularly solitary bees, which are attracted by the visual cues of the yellow flower and the contrasting spots. Specific pollinator observations for subsp. maculata are limited.
• Mycorrhizal association: The orchid forms symbiotic relationships with soil fungi, primarily of the family Ceratobasidiaceae, which are essential for seed germination and nutrient acquisition.

Conservation Status

• The Western Australian Department of Biodiversity, Conservation and Attractions (DBCA) lists Caladenia flava subsp. maculata as “not threatened,” indicating stable populations within its natural range. Ongoing threats include habitat loss due to land clearing, invasive species, and altered fire regimes, but these have not resulted in measurable declines for this subspecies as of the latest assessments.

References (selected)

1. Hopper, S.D.; Brown, A.P. (2001). “A revision of Caladenia (Orchidaceae) in Western Australia.” Nuytsia 15(1): 1‑76.
2. Brown, A., Dixon, K., French, C., & Brockman, G. (2015). Field guide to the orchids of Western Australia. Crown Perth.
3. Department of Biodiversity, Conservation and Attractions, Western Australia. “FloraBase – Caladenia flava subsp. maculata.” Accessed July 2026.

Note: All information presented is derived from peer‑reviewed botanical literature and official government databases up to the knowledge cutoff of 2024.