Gastrodia, Brown, 1810

Bandara, Champika, Atthanagoda, Anusha Gayan, Bandara, Nadeesha Lewke & Kumar, Pankaj, 2023, The study of the tribe Gastrodieae (Orchidaceae, Epidendroideae) in Sri Lanka I: two new species of Gastrodia, Phytotaxa 622 (2), pp. 115-130 : 127

Field identification key to the all Gastrodia species in Sri Lanka

1. Plant height> 40 cm, flowers greenish .................................................................................................................. G. thilakapremae

- Plant height <20 cm, flowers not green ............................................................................................................................................2

2. Perianth tube with a cleft on the front ...............................................................................................................................................3

- Perianth tube fused ............................................................................................................................................................................4

3. Flowers white, smaller in size (1.2 cm broad) ................................................................................................................. G. zeylanica

- Flowers yellow, larger in size (2.1–2.3 cm broad) ..................................................................................................... G. pushparaga

4. Flowers brown, smaller in size (1 cm broad) .......................................................................................................... G. munasinghae

- Flowers white, larger in size (1.8–2.2 cm broad) ................................................................................................ G. gunatillekeorum