Orchidaceae (Orchids) >

Pterostylis angusta is commonly known as the Narrow-hooded Shell Orchid, or just the Narrow Shell Orchid, and is a perennial, deciduous, species of terrestrial orchid that is endemic to the south-west of Western Australia.

Pterostylis angusta (Narrow-hooded Shell Orchid), Great Southern Region WA © Terry Dunham
Pterostylis angusta (Narrow-hooded Shell Orchid), Great Southern Region WA © Terry Dunham

Starting as an underground tuber, the orchid (when not in flower) appears as a rosette of dark, bluish-green leaves. Each leaf is between 10–25 mm long and 7–12 mm wide.

Pterostylis angusta (Narrow-hooded Shell Orchid) leaf rosette, Great Southern Region WA © Terry Dunham
Pterostylis angusta leaf rosette, Great Southern Region WA © Terry Dunham
Pterostylis angusta (Narrow-hooded Shell Orchid) leaf rosette, Great Southern Region WA © Terry Dunham
Pterostylis angusta leaf rosette, Great Southern Region WA © Terry Dunham
Pterostylis angusta (Narrow-hooded Shell Orchid) leaf rosette, Stirling Range National Park WA © Terry Dunham
Pterostylis angusta leaf rosette, Great Southern Region WA © Terry Dunham

When in flower, the plant has a single flower with leaves on the flowering spike. The flower is green, white and brown with an inflated base, a narrow hood and the longest labellum of any Western Australian Pterostylis species.

The specific epithet (angusta) is a Latin word meaning “narrow”, referring to the narrow galea (the galea is an overhanging, helmet-shaped, part of the flower that protects the reproductive part of the flower).

Pterostylis angusta (Narrow-hooded Shell Orchid), Stirling Range National Park WA © Terry Dunham
Pterostylis angusta (Narrow-hooded Shell Orchid), Stirling Range National Park WA © Terry Dunham

The Pterostylis angusta tubers seen here, have been disturbed by a herbivore (most likely by bandicoots or kangaroos).


  • Scientific classification
  • Kingdom: Plantae
  • Phylum: Charophyta
  • Class: Equisetopsida
  • Subclass: Magnoliidae
  • Superorder: Lilianae
  • Order: Asparagales
  • Family: Orchidaceae
  • Genus: Pterostylis
  • Species: Pterostylis angusta

Footnote & References

  1. Pterostylis angusta, Photographs © Terry Dunham
  2. Pterostylis angusta A.S.George, Narrow Hooded Shell Orchid, Atlas of Living Australia, https://bie.ala.org.au/species/https://id.biodiversity.org.au/taxon/apni/51412018

OrchidaceaeOrchidaceae Index Caladenia barbarossa (Dragon Orchid) Caladenia bryceana subsp. bryceana (Dwarf Spider Orchid) Caladenia corynephora (Club-lipped Spider Orchid) Caladenia drummondii (Winter Spider Orchid) Caladenia integra (Smooth-lipped Spider Orchid) Caladenia latifolia (Pink Fairies) Caladenia lobata (Butterfly Spider Orchid) Caleana major (Flying Duck Orchid) Caladenia melanema (Ballerina Orchid) Caladenia polychroma (Joseph’s Spider Orchid) Caladenia pulchra (Slender Spider Orchid) Caladenia pusilla (Tiny Caladenia) Caladenia serotina (Christmas Spider Orchid) Caladenia tessellata (Thick-lip Spider Orchid) Cephalotus follicularis (Western Australian Pitcher Plant) Cryptostylis ovata (Slipper Orchid) Dendrobium kingianum (Pink Rock Orchid) Dendrobium speciosum (Rock Orchid) Drakaea glyptodon (King-in-his-carriage Orchid) Drakaea livida (Warty Hammer Orchid) Elythranthera emarginata (Pink Enamel Orchid) Epiblema grandiflorum (Babe-in-a-cradle Orchid) Ericksonella saccharata (Sugar Orchid) Glossodia major (Wax-lip Orchid) Leptoceras menziesii (Rabbit Orchid) Microtis cupularis (Cupped Mignonette Orchid) Paracaleana nigrita (Flying Duck Orchid) Pterostylis angusta (Narrow-hooded Shell Orchid) Pterostylis cheraphila (Floodplain Rustyhood) Pterostylis ciliata (Hairy Rufous Greenhood) Pterostylis picta (Painted Rufous Greenhood) Rhizanthella johnstonii (Southern Underground Orchid) Spiculaea ciliata (Elbow Orchid) Thelymitra antennifera (Lemon-scented Sun Orchid) Thelymitra sp. Ongerup (Orange Sun Orchids) Thelymitra speciosa (Eastern Queen of Sheba’s)

FloraFlora in Australia Flora Index Acacia Anigozanthos (Kangaroo Paws) Annual Yellowtop Apium prostratum subsp. prostratum var filiforme Apple Bush (Pterocaulon sphacelatum) Australian Bluebell Australian Gossypium Banksia Batswing Coral Tree Billy Buttons Birdsville Indigo Blue Pincushion Bush Banana Callistemon Callitris drummondii (Drummond’s Cypress Pine) Calothamnus quadrifidus Cape Honeysuckle Cassia fistula (Golden Shower) Cattle Bush Common Heath Crotalaria Darwinia wittwerorum (Wittwer’s Mountain Bell) Daviesia oppositifolia (Rattle-pea) Desert Oaks Drumsticks Eremophila Eucalyptus Ficus Flannel Cudweed (Actinobole uliginosum) Georges Indigo Goatshead Burr (Sclerolaena bicornis) Golden Everlasting Goodenia Gossypium Grass and Grasses Grass Trees Grevillea Grey Germander Hakea Kapok Bush (Aerva javanica) Lambertia sp Leptospermum MacDonnell Ranges Cycad Maireana scleroptera Mexican Poppy Minnie Daisy Mistletoe Family Nardoo Native Apricot Nicotiana megalosiphon subspecies sessilifolia Nuytsia floribunda Orange Spade Flower Orchidaceae Parakeelyas (Calandrinia) Pebble Bush (Stylobasium spathulatum) Perennial Yellow Top Pink Everlasting Pink Rock Wort Poached Egg Daisy Portulaca Proteaceae Ptilotus Quandong Resurrection Fern Rosy Dock Ruby Saltbush Santalum Solanum Spike Centaury Spinifex Storkbill (Erodum cygnorum) Striped Mint Bush Sturt’s Desert Pea Sturt’s Desert Rose Tall Saltbush Tangled Leschenaultia Tar Vine Tribulus eichlerianus Upside-down Plant Urodon dasyphylla Variable Daisy Waratah (Telopea) Wertabona Daisy White Cedar (Melia azedarach) White Indigo White Paper Daisy Wild Passionfruit Wild Stock Woolly-Headed Burr Daisy Woolly Bush Yellow-keeled Swainsona