Caladenia longicauda
Caladenia longicauda is a species of plant in the orchid family Orchidaceae and is endemic to the south-west of Western Australia. It is distinguished by its large leaf and by its up to five large, white flowers which have drooping sepals and petals with long, thickish brown "tails".
Description
Caladenia longicauda is a terrestrial, perennial, deciduous, herb with an underground tuber and a single hairy leaf, long and wide. Between July and early November it produces one to three flowers on a stalk tall, each flower wide. The flowers are mostly white except for a few red markings and reddish stripes on the backs of the petals and sepals. The dorsal sepal is green, erect, long and wide with its edges slightly turned inwards. The lateral sepals are long, wide, spreading horizontally near their bases but then drooping. The petals are similar to the sepals but slightly shorter and narrower. The labellum is white, long, wide with erect to spreading teeth up to long along its sides. The middle part of the labellum has the longest teeth on its edge. These teeth are red with hooked white tips. The front part of the labellum curves downwards, with the teeth becoming shorter. There are between four and eight rows of calli along the central part of the labellum, the calli pale to dark red and club-shaped. The fruit is a non-fleshy, dehiscent capsule containing a large number of seeds.Taxonomy and naming
Caladenia longicauda was first formally described by John Lindley in 1840 and the description was published in A Sketch of the Vegetation of the Swan River Colony. The specific epithet is derived from the Latin words longus meaning "long" and cauda meaning "tail".The names of fourteen subspecies of C. longicauda are accepted by the Australian Plant Census:
| Subspecies | Description | Distribution and habitat | Image |
| C. longicauda Lindl. subsp. longicauda | Lateral sepals long, labellum wide | Woodland between Lancelin and Nannup | |
| C. longicauda subsp. albella Hopper & A.P.Br. | Lateral sepals long, labellum wide | Swampy areas between Eneabba and Gingin | |
| C. longicauda subsp. australora Hopper & A.P.Br. | Lateral sepals long, labellum wide | Coastal areas between the Fitzgerald River National Park and Beaufort Inlet | |
| C. longicauda subsp. borealis Hopper & A.P.Br. | Lateral sepals long, labellum wide | Near-coastal areas between Bunbury and Dongara | |
| C. longicauda subsp. clivicola Hopper & A.P.Br. | Lateral sepals long, labellum wide | Forests between North Dandalup and Collie and coastal heath near Dunsborough | |
| C. longicauda subsp. crassa Hopper & A.P.Br. | Lateral sepals long, labellum wide | Swampy places between Esperance and Israelite Bay | |
| C. longicauda subsp. eminens Hopper & A.P.Br. | Lateral sepals long, labellum wide | Widespread between Moore and Ravensthorpe | |
| C. longicauda subsp. extrema A.P.Br. & G.Brockman | Lateral sepals long, labellum wide | Winter-wet areas near Manjimup | |
| C. longicauda subsp. insularis Hopper & A.P.Br. ex A.P.Br. & G.Brockman | Lateral sepals long, labellum wide | Coastal heath near Esperance | |
| C. longicauda subsp. merrittii Hopper & A.P.Br. | Lateral sepals long, labellum wide | Forest between Margaret River and Nannup | |
| C. longicauda subsp. minima A.P.Br. & G.Brockman | Lateral sepals long, labellum wide | Woodland or shrubland near Yuna | |
| Caladenia longicauda subsp. redacta Hopper & A.P.Br. | Lateral sepals long, labellum wide | Woodland between Collie and Mount Barker | |
| C. longicauda subsp. rigidula Hopper & A.P.Br. | Lateral sepals long, labellum wide | On granite outcrops or near streams between Ravensthorpe and Balladonia |