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Frog Greenhood
Pterostylis sargentii C.R.P.Andrews 1905

Synonyms

Notes

The Frog Greenhood is one of the most distinct species among the Banded Greenhood Orchids and readily identified by the long, pointy ends to its lateral sepals and the unique, dark, anvil-shaped labellum. As with all Banded Greenhoods, the labellum is irritable and will flick up when touched, thereby bringing the pollinator in contact with the stigma and pollen. The colour of the flowers is generally quite variable and can range from green to brown.

The Frog Greenhood is common and widespread across WA’s Wheatbelt region south-west of a line from Kalbarri to Israelite Bay where it grows in large numbers in dry forests and woodland. It is particularly common in open wandoo woodland where it thrives in rather harsh conditions in dry bark and leaf litter in places where few other plants manage to survive. Accompanying species include the Little Pink Fairy Orchid and the Sugar Orchid, both of which are equally abundant throughout the Wheatbelt.

There is a closely related species, the Little Frog Greenhood (Pterostylis occulta), which looks almost exactly the same as the Frog Greenhood. However, the Frog Greenhood is readily distinguished from that species by its much earlier winter flowering period (Jul–Aug), broad, smooth, anvil-shaped labellum without white hairs, and the fact that withering flowers turn dark-brown rather than bright-orange. Both species often grow alongside each other, but their flowering times do not overlap.

Photos

Pterostylis sargentii
Tbd. (West Pingelly, WA, 03 / 08 / 2014)
Pterostylis sargentii
Tbd. (West Pingelly, WA, 03 / 08 / 2014)
Pterostylis sargentii
Tbd. (West Pingelly, WA, 17 / 08 / 2014)
Pterostylis sargentii
Near the end of the flowering period the flowers turn brown. (Brookton, WA, 19 / 08 / 2016)
Pterostylis sargentii
Close-up view of the characteristic, anvil-shaped labellum (West Pingelly, WA, 25 / 08 / 2024)
Pterostylis sargentii
Another view of the characteristic labellum (West Pingelly, WA, 25 / 08 / 2024)
Pterostylis sargentii
Tbd. (West Pingelly, WA, 03 / 08 / 2014)
Pterostylis sargentii
Tbd. (Brookton, WA, 19 / 08 / 2016)
Pterostylis sargentii
Frog Greenhoods often grow in the company of other orchids such as the Little Pink Fairy Orchid (depicted here) and the Sugar Orchid. (Brookton, WA, 19 / 08 / 2016)

References