Seeds of South Australia
Caladenia argocalla (Orchidaceae)
Large White Spider-orchid
List of species for Caladenia
Display more images
Click on an image to enlarge it
Seed collecting:
October to November
Herbarium regions:
Northern Lofty, Murray, Southern Lofty
NRM region:
Adelaide and Mount Lofty Ranges
IBRA regions
Fleurieu (KAN02)Kanmantoo
 Critically Endangered   (IUCN: CR B2ab(i,ii,iii,iv,v); D)   (Definite Decline)   [~15 - 20 plants; no viable pops here; very fragmented; could become extinct in next 20 yrs]
Mount Lofty Ranges (FLB01)Flinders Lofty Block
 Endangered   (IUCN: EN B2ab(i,ii,iii,iv,v); D)   (Definite Decline)   [only 1 large pop (150 tubers) in MLR, stronghold in Clare Valley; needs a large pop to remain viable]
Broughton (FLB02) 
 Critically Endangered   (IUCN: CR B1ab(i,iii,iv))   (Definite Decline)   [Disappeared from Nuriootpa & Kapunda. Fluctuation of flowers. Restrictive population, Clare pop most viable. Emu Flat not viable. Weed invasion biggest threat. ]
RSCA map:
Regional Species Conservation Assessments per IBRA subregion. Please click the thumbnail map.
AVH map:
Australian distribution map (external link)
SA Census:
Census of South Australian plants (external link)     [genus Caladenia]
Name derivation:
Caladenia from the Greek 'kallos' meaning beauty and 'aden' meaning a gland, referring to the colourful labellum and the glistening glands at the base of the column that are present in many of the species. Argocalla from the Greek 'argos' meaning white and 'kallos' meaning beautiful, referring to its flower.
Endemic to South Australia and restricted to the Mount Lofty Ranges growing on hills and slopes in eucalyptus and Allocasuarina verticillata open woodland with a herbaceous understorey.
Native. Endangered in South Australia. Endangered in Australia (EPBC Act).
Plant description:
Annual herb growing from an underground tuber, with a single dull green, hairy, linear to narrow lance-shaped leaf to 220 mm long and 18 mm wide appearing in April or May. Leaves or flowers do not appear every year. Inflorescence on a long slender stalk to 60 cm high with one, (sometimes two) white to greenish-white flowers. Perianth segments are white to greenish-white with narrow, dark central stripes. Petals and lateral sepals are spreading then drooping, with the dorsal sepal  incurved. Petals with dark-red, glandular filiform tips that are not perfumed. The labellum is ovate-cordate and strongly recurved. The lamina is white-green or crimson, margins fringed with teeth and 6 to 8 rows of crimson, red or white club-shaped calli extending nearly to apex in the middle. Flowering between September and October.
Fruit type:
Pale-brown hairy, papery ellipsoid capsule containing numerous tiny seeds.
Seed collecting:
Collect fat capsules as they start to dry and turn brown. Pods will split and release the seeds quickly and will require monitoring. To increase the chances of collecting mature pods, it is recommended that a small breathable bag (ie. Organza bags) be used to enclose the developing capsules.
Seed cleaning:
Place the capsules in a container that will hold fine seeds and leave to dry for a few weeks or until the capsule split. Then carefully hold the capsule and tap it gently to release the seeds. Store the seeds with a desiccant such as dried silica beads or dry rice, in an air tight container in a cool and dry place, refrigerator or in liquid nitrogen.