Ethnobotanical Leaflets 12: 388-390. 2008.

Arisaema agasthyanum Sivadasan & Sathish. ( Araceae ): A New Record for Tamil Nadu, India

R. Kottaimuthu* and R. Ganesan*

Ashoka Trust for Research in Ecology and the Environment (ATREE), Bangalore

kottaimuthu@yahoo.co.in

Issued 12 June 2008

Abstract

Arisaema agasthyanum Sivadasan et Sathish., is recorded for the first time for Tamil Nadu from Tirunelveli Hills, Western Ghats, Tamil Nadu. India.

Introduction

During intensive botanical exploration in Tirunelveli Hills, Western Ghats, Tamil Nadu, an interesting aroid was collected. Critical studies have confirmed it as Arisaema agasthyanum. Perusal of literature revealed that this species was known so far from only its type locality, Agasthyamalai, Trivandrum District, Kerala State (Sivadasan & Sathishkumar, 1987). It has not been previously collected or reported from Tamil Nadu State (Bhargavan, 1989; Manickam et al., 2003; Thiyagaraj, 1994; Thiyagaraj & Daniel, 2002). Hence, the present collection is an addition to the aroids of Tamil Nadu.

As a detailed description is provided elsewhere by Sivadasan & Sathishkumar (1987), only a brief description and a photograph is provided here for the easy identification of this species in the field.

Species Description

Arisaema agasthyanum Sivadasan et Sathish., in Aroideana 10: 18. 1987.

Dioecious, cormous herbs, 18 – 45 cm high; corms 1- 2 cm across, depressed globose. Cataphylls 3, 2.5 – 10 x 1 – 3.5 cm, apex acute. Leaf solitary; petiole 10 – 40 cm long, basally sheathing for 6 cm and sheath tip short liguled; leaflets 5 – 8, radiate, oblong – obovate / elliptic, 6 – 9 x 2 – 3 cm , base cuneate, acuminate at apex. Inflorescence short – peduncled, peduncle 2 – 7 cm long, completely enclosed in the petiolar sheath. Spathe 10 – 15 cm long, limb galeiform with basal auricular extensions. Spadix 4 – 5.5 cm long, dioecious, sessile. Staminate spadix 1 – 1.5 cm long, neuter flowers absent. Pistillate spadix 1 – 1.5 cm long; appendix 2 – 4 cm long, subcylindric. Fruits not collected.

Flowering: May

Distribution: Endemic to Western Ghats of Kerala and Tamil Nadu, India.

Specimens examined: Western Ghats: Tamil Nadu: Tirunelveli District: On way to Poongulam from Veiyilar, 1358m, 29-5-2008, R. Kottaimuthu 59 & On the slopes of Agasthyamalai, 1780m, 29-5-2008, R. Kottaimuthu 80.

Notes: The genus Arisaema Martius includes more than 200 species in fifteen sections distributed in Eastern Asia – the centre of distribution, Africa ( Ethiopia ), Eastern North America and Mexico (Sivadasan, 1984). In Tamil Nadu, the genus is represented by 10 species viz., Arisaema auriculatum Barnes, A. barnesii Fischer, A. jethompsonii Thiyagaraj & Daniel, A. leschenaultii Blume, A. murrayi (Graham) Hook., A. tortuosum (Wall.) Schott., A. transluscens Fischer, A. tuberculatum Fischer, A.tylophorum Fischer and A. wightii Schott. The addition of the present taxon increases the representative species of the genus to 11 in Tamil Nadu.

Plate 1. Arisaema agasthyanum Sivadasan & Sathish.

Acknowledgement

We express our sincere thanks to Mr. Ponnuchamy, French Institute of Pondicherry, for providing necessary literature.

Bibliography

Bhargavan, P. 1989. Araceae In: A. N. Henry, V. Chithra and N. P. Balakrishnan. (eds.), Flora of Tamil Nadu, India, Series I: Analysis, Volume Three, Botanical Survey of India, Coimbatore: pp. 54 – 59.

Manickam, V. S., Jothi, G. J., Murugan, C. and Sundaresan, V. 2003. Check-list of the Flora of Tirunelveli Hills, Southern Western Ghats, India, St. Xavier’s College, Palayamkottai, Tamil Nadu, India: pp. 176 – 178.

Sivadasan, M. 1984. A new species of Arisaema (Araceae) from South India. Kew Bull. 40(4): 801 – 803.

Sivadasan, M. and Sathishkumar, C. 1987. A new species of Arisaema (Araceae) from India with a note on variation and evolution of staminate flowers. Aroideana 10: 18 – 21.

Thiyagaraj, G. J. 1994. Studies on the South Indian Araceae Ph. D. Thesis, Madurai Kamaraj University, Madurai (Unpublished)