Spiranthes triloba (Small) K. Schum. emend. M.C. Pace
Panther Ladies' Tresses
Facts About
Accepted Synonyms: Gyrostachys triloba, Spiranthes ×folsomii, Spiranthes ×itchetuckneensis
Spiranthes triloba, the Panther Ladies’ Tresses, is endemic to Florida and has recently been reinstated as a valid species. This orchid has a basal rosette of 1-5 upright leaves that may wither at the time of flowering, and slender, stoloniferous roots that produce small plantlets. The inflorescence is a spike of fragrant, white flowers arranged in a coiled spiral. The papillate, white margined labellum matures from lime-green to yellow and distinguishes this orchid from other Spiranthes species. This orchid is usually found in frequently burned prairies and open flatwoods.
The status for Spiranthes triloba has not been reported, although this orchid should be of high conservation concern given its limited distribution and preference for fire-dependent habitat. Many populations may be at risk from salt water intrusion or submersion from predicted sea level rise.
Pollination
Although fruits are regularly encountered in the field, cultivated plants of S. triloba grown in a greenhouse have not produced fruits. This observation and the presence of a well-developed rostellum support the conclusion that this orchid most likely requires a vector to initiate pollination for seed production. Insect visitors include Apis mellifera and Augochlora pura, but their role as pollinators has not been confirmed.
Notes on Subspecies and Varieties
Generally considered a hybrid or a “green-lipped Spiranthes odorata”, this orchid was originally described as a distinct species over 100 years ago. Morphological characters and molecular studies confirm that its recognition as a distinct species is warranted.
Ecosystem Type
Disturbed habitats, grassland, prairie, savanna, woodlands
Characteristics
- Habitat:
- terrestrial
- Leaf arrangement:
- basal
- Number of leaves on stem:
- absent
- Form of the labellum:
- the labellum is not pouch-like
- Labellum outline:
- the labellum is simple
- Main color of labellum:
-
- green to brown
- yellow
- Nectar spur:
- absent
- Inflorescence type:
- the inflorescence is a spike
- Labellum characteristics:
- the labellum is simple
- Labellum length:
- 5–8 mm
- Sepal length:
- 5–8.8 mm
- Plant height:
- 20–60 cm
-
Flowers
- Floral bract length:
- 7–14 mm
- Flower petal color:
- white
- Flower symmetry:
- the flower is zygomorphic
- Flowering date:
-
- January
- February
- October
- November
- December
- Form of the labellum:
- the labellum is not pouch-like
- Inflorescence type:
- the inflorescence is a spike
- Labellum characteristics:
- the labellum is simple
- Labellum length:
- 5–8 mm
- Labellum outline:
- the labellum is simple
- Labellum position:
- the flowers are resupinate
- Length of peduncle:
- 200–600 mm
- Lower petal strongly red-veined:
- no
- Main color of labellum:
-
- green to brown
- yellow
- Nectar spur:
- absent
- Number of stamens:
- 1
- Orientation of side petals:
- the lateral petals are ascending
- Self-pollinating flowers:
- there are no cleistogamous flowers
- Sepal length:
- 5–8.8 mm
- Sepals fused only to sepals:
- the sepals are separate from one another
- Shape of viscidium:
- linear
- Spots on labellum:
- no
-
Fruits or seeds
- Seed capsule orientation:
- the capsule points upwards or outwards
-
Growth form
- Plant height:
- 20–60 cm
- Roots:
- the rhizomes are non-coralloid
- Underground organs:
- slender roots
- myco-heterotrophic or not:
- the plant is chlorophyllous
-
Leaves
- Bract relative length:
- the bract is longer than the associated flower
- Leaf arrangement:
- basal
- Leaf blade edges:
- the leaf edges are entire
- Leaf blade length:
- 55–236 mm
- Leaf blade shape:
-
- lanceolate
- linear
- oblanceolate
- Leaf blade tip:
- the tip of the leaf blade is acuminate
- Leaf blade width:
- 7–21 mm
- Leaves during flowering:
- leaves are present during flowering
- Number of bracts on stem:
- Up to 2
- Number of leaves on stem:
- absent
-
Place
- Ecosystem type:
-
- disturbed habitats
- grasslands
- prairie
- savanna
- woodlands
- Habitat:
- terrestrial
- Location:
- Florida
-
Facts and Uses
- Mycorrhiza
- Monitoring
- Propagation
- Restoration
Native to North America
Yes
North American Conservation Status & Distribution
Conservation Status
Conservation and Wetland Status | |
---|---|
Global Rank | N/A |
US Status | N/A |
Canadian Status | N/A |
Conservation status for: Florida | |
---|---|
Global Rank | N/A |
US Status | N/A |
Florida Rank | N/A |
Florida Status | N/A |
Canadian Status | N/A |
Wetland Status | N/A |