Journal of Threatened Taxa | www.threatenedtaxa.org | 26 January 2022 | 14(1): 20523–20525

 

 

ISSN 0974-7907 (Online) | ISSN 0974-7893 (Print) 

https://doi.org/10.11609/jott.6377.14.1.20523-20525

#6377 | Received 09 July 2020 | Final received 13 November 2020 | Finally accepted 22 December 2021

 

 

Robiquetia gracilis (Lindl.) Garay—a new record to the flora of Anamalai Hills, Tamil Nadu, India

 

B. Subbaiyan 1, V. Ganesan 2, P.R. Nimal Kumar 3  & S. Thangaraj Panneerselvam 4

 

1 Anamalai Tiger Reserve Forest Pollachi, Tamil Nadu, India.

2 Coimbatore, Tamil Nadu, India.

3 Orchid Conservationist, Plantart Botanic Private Limited, Coimbatore, Tamil Nadu, India.

4 Anamalai Tiger Reserve Forest Pollachi, Tamil Nadu, India.

1 bsubbaiyan@gmail.com (corresponding author), 2 ganesanifs93@gmail.com (corresponding author), 3 nk@plantart.in, 4 stpselephant@gmail.com

 

 

Editor: Anonymity requested.   Date of publication: 26 January 2022 (online & print)

 

Citation: Subbaiyan, B., V. Ganesan, P.R.N. Kumar & S.T. Panneerselvam (2022). Robiquetia gracilis (Lindl.) Garay—a new record to the flora of Anamalai Hills, Tamil Nadu, India. Journal of Threatened Taxa 14(1): 20523–20525. https://doi.org/10.11609/jott.6377.14.1.20523-20525

 

Copyright: © Subbaiyan et al. 2022. Creative Commons Attribution 4.0 International License.  JoTT allows unrestricted use, reproduction, and distribution of this article in any medium by providing adequate credit to the author(s) and the source of publication.

 

Funding: Self-funded.

 

Competing interests: The authors declare no competing interests.

 

Acknowledgements: Our sincere thanks are due to Botanical Survey of India, Southern Regional Center Coimbatore, for permitting us to consult the herbarium and library, and the Tamil Nadu State Forest Department for providing the opportunity to conduct the survey of plants in the Anamalai Tiger Reserve.

 

 

Robiquetia, an indispensable genus of the family Orchidaceae, was first described by Gaudichaud-Beaupréin, 1829 in his work  “Voyage autour du monde”; it belongs to the tribe Vandeae. It encompasses about 70 species which are distributed from India and Sri Lanka to Samoa (Cootes 2011; Ormerod 2017).  In India, the genus is represented by four species (Robiquetia gracilis, R. jossephiana, R. spathulata, and R. succisa), of which Robiquetia jossephiana is known to be endemic to Kerala (Kumar & Manilal 1992, 1994; Jalal & Jayanthi 2012).

Anamalai Tiger Reserve (ATR) is carved out of the Tamil Nadu portion of the Anamalais. It lies south of the Palakkad gap in the southern Western Ghats mountain chain. Geographically, it is located between the longitudes 76.821–77.356E and latitudes 10.220–10.555N. The two important UNESCO World Heritage Sites of Western Ghats such as the Karian Shola and the Grass hills are located within the ATR. 

Frequent field surveys by the authors (2017–2019) in Anamalai hills has resulted in locating a number of rare and unknown species of plants which included a specimen of an interesting orchid species of the genus Robiquetia. Specimens were collected from two localities in Valparai plateau and were kept at Anamalai orchidarium for monitoring, on initiation of the inflorescence, the authors visited the site and observed the flowering and fruiting and recorded the same. A detailed taxonomic study with perusal of relevant literature (Kumar & Manilal 1994; Sasidharan 2013) and consultation with experts confirmed its identity as Robiquetia gracilis, a rare species, till now not reported from the Anamalai hills. In Tamil Nadu this species was reported in Kakachi-Kodayar, Kalakkad-Mundathurai Tiger Reserve (KMTR; Ganesan & Livingstone 2001) and Athirumala and Agasthymala of Kerala (Sasidharan 2013). Based on scrutiny of the specimen, it was confirmed that the species exists in the Anamalais ranging 1,100–1,400 m altitude. It is a new record to the flora of Anamalai hills. Robiquetia gracilis can be distinguished from other species by the zig-zag and sheathed stem character. Meanwhile, tiny white flowers with red dots confirm its identification in the wild. Ganesan & Livingston (2001) reported  the habitat of Robiquetia gracilis as mid-elevation evergreen forest (1,200–1,550 m) areas of KMTR.

 

Robiquetia gracilis (Lindl.) Garay

Bot. Mus. Leafl. Harvard Univ. 23: 197. 1972

Saccolabium gracile Lindl., Gen. Sp. Orchid. Pl. 225. 1833. (Image 1)

Monopodial, pendulous, epiphyte. Roots: branched, terete, elongate, emerging from nodes up to 25 cm long. Stems 10–15 cm long, semi hard, zigzag, green sheathed. Leaves alternate 6–12 x 0.5–0.7 cm, linear-lanceolate, acuminate at apex, sheathed at base. Inflorescence leaf opposed, drooping raceme, 8–12 cm long. Peduncles filiform, 12–16 flowered. Flowers, white, 0.4–0.5 cm across. Sepals and petals 0.15–0.2 cm long, linear, subulate. Lip 0.3–0.4 cm long, spurred, lateral lobes; mid-lobe small. Column 0.1–0.15 cm long; foot 0. Pollinia 2, globose, attached to long slender caudicle. Pedicels and ovary 0.3–0.35 cm long. Capsules subglobose, 0.5 × 0.4 cm.

Habit: Grows as epiphytic herbs in association with Garcinia morella (Gaertn.) Desr.

Habitat: Evergreen forests between 1,100–1,400 m.

Specimens examined: India, Tamil Nadu, Coimbatore district, Anamalai Tiger Reserve, 2018, Ganesan & Subbaiyan (0055; Image 2) Anamalai Herbarium, Pollachi.

Distribution: Southern India (Kerala, Tamil Nadu) and Sri Lanka.

Flowering & Fruiting: August–January.

Notes: A very few individuals of this species were identified in the collection locality. The species has not been recorded earlier in any localities of the reserve so far. Therefore, it is suggested that an exploration in other possible localities is essential to assess its exact conservation status. Two live specimens are deposited in Anamalai Orchidarium at Attakatti for conservation purpose.

 

 

For images - - click here

 

 

References

 

Cootes, J.E. (2011). Philippine Native Orchid Species. Katha Publishing Co., Inc., Quezon City, 289pp.

Ganesan, R. & C. Livingstone (2001). Checklist of orchids from a mid elevation evergreen forest at Kakachi-Kodayar, Kalakkad-Mundanthurai Tiger Reserve, Agasthyamalai, southern Western Ghats. Zoos’ Print Journal 16(3): 445–446. https://doi.org/10.11609/JoTT.ZPJ.16.3.445-6

Jalal, J.S. & J. Jayanthi (2012). Endemic orchids of peninsular India: a review. Journal of Threatened Taxa 4(15): 3415–3425. https://doi.org/10.11609/JoTT.o3091.3415-25

Kumar, C.S. & K.S. Manilal (1992). Epiphytes orchids of India. Rheedea 2(2): 80–100.

Kumar, C.S. & K.S. Manilal (1994). A Catalogue of India Orchids. Bishen Singh Mahendra Pal Singh, Dehradun, 84pp.

Ormerod, P. (2017). Checklist of Papuasian Orchids. Nature & Travel Books, Lismore (Australia), 496pp.

Sasidharan, N. (2013). Flowering Plants of Kerala: CD-ROM ver. 2.0. Kerala Forest Research Institute, Peechi, Kerala.