Pteris geminata Wall. ex J. Agardh (Pteridaceae): a Critically Endangered Pteridophyte in India

 

V.K. Sreenivas 1 & P.V. Madhusoodanan 2

 

1 Department of Botany, Sri Vyasa N.S.S. College, Wadakanchery, Thrissur District, Kerala 680623, India

2 Malabar Botanical Garden, Calicut, Kerala 673014, India

1 sreenivasvk@gmail.com (corresponding author), 2 pvmadhu@gmail.com

 

 

doi: http://dx.doi.org/10.11609/JoTT.o3564.5875-7

 

Editor: V. Irudayaraj, St. Xavier’s College, Tirunelveli, India                       Date of publication: 26 June 2014 (online & print)

 

Manuscript details: Ms # o3564 | Received 26 August 2013 | Final received 07 February 2014 | Finally accepted 20 May 2014

 

Citation: Sreenivas, V.K. & P.V. Madhusoodanan (2014). Pteris geminata Wall. ex J. Agardh (Pteridaceae): a Critically Endangered Pteridophyte in India. Journal of Threatened Taxa 6(6): 5875–5877; http://dx.doi.org/10.11609/JoTT.o3564.5875-7

 

Copyright: © Sreenivas & Madhusoodanan 2014. Creative Commons Attribution 4.0 International License. JoTT allows unrestricted use of this article in any medium, reproduction and distribution by providing adequate credit to the authors and the source of publication.

 

Funding: Kerala State Council for Science, Technology and Environment (KSCSTE).

 

Competing Interest: The authors declare no competing interests.

 

Acknowledgements: The first author is deeply indebted to Kerala State Council for Science, Technology and Environment (KSCSTE) for proving research fellowship in taxonomy.  We are thankful to the Director, Botanical Survey of India (CAL), Kolkata, for allowing examining the Wallichian Herbaria. We are also grateful to Kerala Forest Department to permit to collect the specimens from Periyar Tiger Reserve, Kerala.

 

 

For figures, images -- click here

 

 

The genus Pteris is commonly known as ‘Brake ferns’ and was established by Linnaeus (1753).  It is estimated to contain about 250 species (Tryon et al. 1990) in the world.  In India, the genus is represented by 50 species (Fraser-Jenkins 2008), though Chandra (2000) reported 45 species, two subspecies and two varieties.  The pantropical genus Pteris in India is found in the eastern Himalayan region of northeastern India and the Western Ghats of southern India.  Manickam & Irudayaraj (1992) reported 15 species of Pteris from the Western Ghats, and later several authors added new species and new records to the southern Indian fern flora.  Some of the species of Pteris are very rare and their representation in various herbaria is scanty.  P. geminata is a threatened species and has been reported from Palakkad and Idukki districts of Kerala and Coimbatore, Nilgiri and Tirunelveli districts of Tamil Nadu (Manickam & Irudayaraj 1992).  Wallich (1828) catalogued this species from ‘India orientalis’ without any description, but later Agardh (1839) validly published this species.  P. geminata is characterized by its veins ending in hydathodes (vein not reaching the margin).  The sterile pinnule and apex of the fertile pinnule is crenate and the lower pair of veins are united to form costal areoles along the midrib.

Materials and methods: The present study is based on the field trips conducted from May 2007 to April 2010 in different parts of southern India including biosphere reserves, national parks, and wild life sanctuaries.  Apart from this, specimens deposited in CAL, CALI, KFRI, MGMC, MH, RHT, SKU, TBGT, XCH were also examined.  But, this species could be collected only from the Periyar Tiger Reserve, Idukki, Kerala (V.K. Sreenivas 124025, CALI).

 

Pteris geminata Wall. ex J. Agardh, Recens. Spec. Pter. 31. 1839. (Image 1; Figs 1 & 2)

Material examined: Reg. No. 124025,  22.iii.2009, Idukki District, Kerala, Near Injippara-Periyar Tiger Reserve (alt. 900m), coll. V.K. Sreenivas.

Type: Nepal, Wallich 2180 (CAL!; CALI, Microfishe!).

Syn: Campteria anamallayensis Bedd., Ferns S. India 14. pl. 45. 1863.

Height 60–70 cm.  Rhizome erect to suberect, 4–6 cm long x 4–6 cm thick, cylindrical with tuft of stipes, scaly. Palea light brown, 3–5 mm long, 0.4–0.6 mm wide at base, lanceolate, entire, acuminate, auriculate, thin uniformly. Stipe 45–55 cm long, 3–6 mm thick, green (fresh specimens) or stramineous (dry materials) above and chestnut below, grooved throughout, glabrous above, scaly below.  Lamina bipinnate, 35–45 cm long x 25–30 cm broad, ovate, basal pair bipartite, herbaceous (thin).  Pinnae 5–7 pairs, 20–25 cm long x 4-6 cm broad, opposite, ovate, acute, basal pinna bipartite, green, and glabrous. Pinnules 16–23 pairs, 30–50 cm long x 3–9 mm broad, oblong, acute, crenate (sterile), only apex is crenate in fertile ones, sinus
c. 3mm away from costa, 2mm apart, glabrous.  Costae grooved above with short inconspicuous spines at the base of costules, and raised below. Veins 13–16 pairs, free, forking, distinct, lower pair of veins form costal areoles along midrib, veins ending submarginally in hydathodes.  Sori brown, linear, crowded, 1.2–2 cm long, marginal except at base and apex. Indusium false, brown at maturity.  Sporangium: capsule globose, 200Ķm long; stalk 250Ķm long, biseriate; annulus 18–22 celled.  Paraphyses uniseriate.  Spores brown, c. 45x50 μm, trilete-tetrahedral, rugate.

Habitat: A rare species present only in moist evergreen forests at high altitudes (800–2300 m).

Notes: It was found that the population of this species is decreasing at an alarming rate due to habitat destruction and climate change.  Recently, Chandra et al. (2008) included this species in the ‘Critically Endangered’ category.  A cursory look at the population based on the IUCN Red List (2001) seems that the species meets the criteria B1ac(iii) under the Endangered category. So it is proposed to conserve the species by vegetative propagation as well as clonal propagation by tissue culture methods.

 

References

 

Agardh, J.G. (1839). Recensio Specierum Generis Pteridis. Lund, Leipzig, 31pp.

Chandra, S. (2000). The Ferns of India. International Book Distributors, Dehra Dun, 37pp.

Chandra, S., C.R. Fraser-Jenkins, A. Kumari & A. Srivasthava (2008). A summary of the status of threatened pteridophytes of India. Taiwania 53: 170–209.

Fraser-Jenkins, C.R. (2008). Taxonomic Revision of Three Hundred Indian Subcontinental Pteridophytes with A Revised Census-list. Bishen Singh Mahendra Pal Singh, Dehra Dun.

IUCN (2001). IUCN Red List Categories and Criteria: Version 3.1. IUCN Species Survival Commission. IUCN, Gland, Switzerland and Cambridge, UK.

Linnaeus, C. (1753). Species Plantarum. Laurentii Salvii, Holmiae, 1073–1077pp.

Manickam, V.S. & V. Irudayaraj (1992). Pteridophyte Flora of the Western Ghats - South India. B. I. Publications, New Delhi, 50–51pp.

Tryon, R.M., A.F. Tryon & K.U. Kramer (1990). Pteridaceae, pp. 230–256. In: Kramer, K.U. & P.S. Green, (eds.). The Families and Genera of Vascular Plants - Volume 1. Pteridophytes and Gymnosperms. Springer Verlag, Berlin.

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