Caladenia longicauda Lindl. 1840 SUBGENUS Calonemorchis Photo courtesy of Malcolm Thomas of Australia

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Common Name The Long Petaled Caladenia - The Large Whiote Spider Orchid
Flower Size 2.4 to 3.6" [6 to 9 cm]
This large sized, cool to cold growing terrestrial species is from South Western Australia at elevations of 100 to 300 meters in open woodlands with a single downy leaf that blooms in the spring on an erect, 30" [85 cm] long, 1 to 5 flowered inflorescence
Synonyms Arachnorchis longicauda (Lindl.) D.L.Jones & M.A.Clem. 2001; Caladenia patersoni var. longicauda (Lindl.) R.S.Rogers 1920; Calonema longicauda (Lindl.) Szlach. 2001; Calonemorchis longicauda (Lindl.) Szlach. 2001
References W3 Tropicos, Kew Monocot list , IPNI ;
Flora's Orchids Nash & La Croix 2005; Native Orchids of Australia Jones 2006
Caladenia longicauda Lindl. var eminens

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Common Name The Large Caladenia - the Stark White Spider Orchid
Flower Size 3.2 to 4.8" [8 to 12 cm]
This terrestrial species is from Western Australia at elevations of 150 to 300 meters in grasses and scrub in open woodlands and is a color variation of the previous species. Differs from the norm in the larger white flower broad lateral sepals and petals the distinctly heart shaped labellum and the short column.
Synonyms Arachnorchis longicauda subsp. eminens (Domin) D.L.Jones & M.A.Clem. 2002; Caladenia eminens (Domin) M.A. Clem. & D.L. Jones 1989; Calonema eminens (Domin) Szlach. 2001; Caladenia longicauda subsp. eminens (Domin) Hopper & A.P.Br. 2001; Caladenia longicauda var. eminens Domin 1912; Calonemorchis eminens (Domin) Szlach. 2001 An Illustrated Encyclopedia of Orchids Pridgeon 1982 as Caladenia eminems; Manual of Orchids Stewart 1995 as Caladenia eminens; Native Orchids of Australia Jones 2006
Caladenia longicauda subsp. merrittii Hopper & A.P.Br. 2001

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Common Name Merrit's White Spider Orchid
Flower Size 8" [20 cm]
Found in Western Australia at elevations of 50 to 250 meters and differs in it's extremely long, thin lateral sepals and petals and narrow labellum and blooms in the spring on a 1 to 4 flowered inflorescence
SynonymsArachnorchis longicauda subsp. merrittii (Hopper & A.P.Br.) D.L.Jones & M.A.Clem. 2002
References W3 Tropicos, Kew Monocot list , IPNI ; Native Orchids of Australia Jones 2006