Orchidoideae

The Orchidoideae, or the orchidoid orchids, are a subfamily of the orchid family (Orchidaceae

Orchidaceae

The Orchidaceae, commonly referred to as the orchid family, is a morphologically diverse and widespread family of monocots in the order Asparagales. Along with the Asteraceae, it is one of the two largest families of flowering plants, with between 21,950 and 26,049 currently accepted species,...

).

They typically contain the orchids with a single (monandrous

Monandrous

- In orchids :A distinction between monandrous and other flowers is particularly relevant in the classification of orchids. The monandrous orchids form a clade consisting of the subfamilies Orchidoideae, Vanilloideae, and Epidendroideae. The other subfamilies, Apostasioideae and Cypripedioideae,...

), fertile anther which is erect and basitonic.

The subfamily Orchidoideae and the previously recognized subfamily Spiranthoideae are considered the closest allies in the natural group of the monandrous orchids because of

• a shared terrestrial
  Terrestrial plant
  A terrestrial plant is one that grows on land. Other types of plants are aquatic , epiphytic , lithophytes and aerial ....
  
   habit
• sectile (capable of being severed) or granular pollinia
  Pollinium
  Pollinium, or plural pollinia, is a coherent mass of pollen grains in a plant.They are the product of only one anther, but are transferred, during pollination, as a single unit. This is regularly seen in plants such as orchids and many species of milkweeds .Most orchids have waxy pollinia...
  
  
• erect anthers.

The Orchidoideae contain two subclades with the following tribes :

• tribes Orchideae and Diseae
• tribes Cranichideae and Diurideae

The former subfamily Spiranthoideae is now embedded as tribe Cranichideae in the clade

Cladistics

Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...

 of the Orchidoideae. It is sister to the tribe Diurideae.

The tribe Orchideae consists of the following subtribes:

• Habenariinae
• Orchidinae

The tribe Diseae consists of the following subtribes:

• Disinae
• Satyriinae

The monophyletic tribe Cranichideae consists of the following monophyletic subtribes :

• Achlydosinae
• Pterostylidinae
• Chloraeinae
• Goodyerinae s.l. (including former Pachyplectroninae)
• Galeottiellinae
• Manniellinae
• Cranichidinae s.l. (including former Prescottiinae)
• Spiranthinae

The tribe Diurideae consists of the following subtribes :

• Acianthinae (monophyleric)
• Caladeniinae (polyphyletic)
• Cryptostylidinae (monophyletic)
• Diuridinae (monophyletic)
• Drakaeinae (monophyletic)
• Prasophyllinae(monophyletic)
• Thelymitrinae (monophyletic)