Blotched Hyacinth-orchid

Appearance

''Dipodium punctatum'' is a leafless, tuberous, perennial, mycoheterotrophic herb. Between five and sixty pale to bright pink flowers with heavy red blotches and 20–25 mm wide are borne on a green to blackish, hyacinth-like flowering stem 40–100 cm tall. The sepals and petals are linear to elliptic or lance-shaped, 10–20 mm long, 2.5–5 mm wide and free from each other with their tips sometimes slightly curved backwards. The labellum is 12–16 mm long, 5–6 mm wide and has three lobes. The centre lobe has a band of pink to mauve hairs, the band narrow near the base but widening towards the tip of the lobe. Flowering occurs from November to March.

This orchid is often confused with ''D. roseum'' but has a narrower band of labellum hairs, darker blotches and less recurved sepals and petals.

Naming

This orchid was first formally described in 1804 by English botanist James Edward Smith in the journal ''Exotic Botany''. Smith gave it the name ''Dendrobium punctatum''. In 1810, Scottish botanist Robert Brown placed the species in his newly described genus ''Dipodium'', publishing the change in ''Prodromus Florae Novae Hollandiae et Insulae Van Diemen''. The specific epithet is derived from the Latin word ''punctum'' meaning "little hole", "dot" or "point".

The World Checklist of Selected Plant Families records this species as a synonym of ''Dipodium squamatum''.

Distribution

The blotched hyacinth orchid is common in woodland and forest along the coast and ranges of New South Wales, the Australian Capital Territory and Queensland. It is also widespread in Victoria especially in the east of the state. There are a few records of the species from the far south-east corner of South Australia.

''Dipodium punctatum'' does not occur in Tasmania. Plants in that state previously classified as ''D. punctatum'' are currently referred to ''D. roseum'', which was described in 1991.

In South Australia, ''D. punctatum'' is listed as endangered. Populations currently included within ''D. roseum'' and ''D. campanulatum'' were originally part of a wider circumscription of ''D. punctatum'' in South Australia.

Habitat

The blotched hyacinth orchid is common in woodland and forest along the coast and ranges of New South Wales, the Australian Capital Territory and Queensland. It is also widespread in Victoria especially in the east of the state. There are a few records of the species from the far south-east corner of South Australia.

''Dipodium punctatum'' does not occur in Tasmania. Plants in that state previously classified as ''D. punctatum'' are currently referred to ''D. roseum'', which was described in 1991.

In South Australia, ''D. punctatum'' is listed as endangered. Populations currently included within ''D. roseum'' and ''D. campanulatum'' were originally part of a wider circumscription of ''D. punctatum'' in South Australia.