Bot. Bull. Acad. Sin. (2003) 44: 175-177

Santhosh Kumar et al. — Memecylon agastyamalaianum, a new species from India

Memecylon agastyamalaianum (Melastomataceae), a new species from India

E.S. Santhosh Kumar*, Raju Antony, and A.E. Shanavas Khan

Tropical Botanic Garden and Research Institute, Palode Thiruvananthapuram District, Kerala 695562, India

(Received September 11, 2001; Accepted February 21, 2002)

Abstract. Memecylon agastyamalaianum Santhosh, Raju & Shanavas, a new species of Melastomataceae from India, is described and illustrated. This new species is allied to M. manickamii C. Murugan, Sundaresan et Jothi.

Keywords: India; Kerala; Melastomataceae; Memecylon agastyamalaianum; New species.

Introduction

The genus Memecylon L. consists of about 150 species, mainly in the Old World tropics (Mabberley, 1987). In India, the genus is represented by about 33 species (Clarke, 1879; Santapau and Henry, 1972), of which 13 are endemic to peninsular India (Nayar, 1996).

The Agastyamalai "hot spot" lies between 8º51'-9º0' N. latitude and 77º0'-77º05' E longitude. It has an area of about 2450 km² and comprises three well protected wildlife sanctuaries, Chenduruni, Neyyar, and Peppara. Different altitudinal ranges, rich rainfall, and varied types of vegetation together make a unique flora with about 189 species exclusively endemic to this "hot spot." The authors conducted an expedition as a part of an ex-situ conservation programme of the medicinal plants of Kerala. This resulted in the discovery of an interesting species of Memecylon, which was clearly different from the hitherto described species of the genus (Clarke, 1879; Gamble, 1919; Bremer, 1979; Murugan et al., 2000). This species is described and illustrated here as new.

Memecylon agastyamalaianum Santhosh, Raju et Shanavas, sp. nov.—TYPE: India, Kerala State, Thiruvananthapuram District, Agastyamalai Hills, Bonaccord, 850 m 8 July 1999, Santhosh Kumar TBG& RI 37656 (holotype: TBGT; isotype: K, CAL, MH). Figure 1

Memecylon manickamii C. Murugan, Sundaresan et Jothi., arcte affinis, sed inflorescentiis axillaribus paucifloribus pedunculis brevibus (0.5 cm longis) teretibus, pedicellis 4-5 mm longis, et ramulis acute 4-angulatis differt.

Large shrubs or small trees, 2-3.5 m high; bark grayish-black, shallowly fissured; branchlets acutely 4-angular.

Leaves opposite, 1.5-2.5 × 0.5-1 cm, elliptic, cuneate-attenuate at base, entire at margin, obtuse or emarginate at apex; midrib with indistinct intramarginal and lateral veins, coriaceous, drying dull greenish-yellow; foliar sclereid filiform. Inflorescences axillary 2-5-flowered umbellate cymes; peduncle 0.5 cm long, terete; pedicels 4-5 mm long, slender, pink; bracts 0.3-0.5 mm long. Flower buds obtuse-rounded at apex with exposed petals; expanded flowers 4-6 mm across. Calyx pink, campanulate, 1.8-2.2 mm across, shallowly 4-lobed, papillate on the outer surface. Petals 4, blue, broadly elliptic-obovate, to 2 × 2.2 mm, shortly clawed at base, acute or apiculate at apex. Disc shallowly striate. Stamens 8, equal; filaments slender, to 2.5 mm long; anthers 1 mm long, connective with a gland. Ovary unilocular, placentation free-central; ovules 4-5; style subulate; 3-3.5 mm long; stigma simple. Fruit globose, 7-8 mm in diameter, crowned by calyx. Seed 1; embryo with wrinkled cotyledons and long hypocotyl.

Additional specimens examined. India. Kerala State, Thiruvananthapuram District, Agastyamala Hills, Bonaccord, alt. 850 m, 22 Jun 2001, Santhosh Kumar TBG & RI 45829 (TBGT).

Phenology. Flowering commences during June, and fruits are seen during August- September.

Etymology. The specific epithet refers to the type locality, the renowned biological "hot spot" of the Agastyamalai Hills.

Distribution. Known only from the type locality, Bonaccord in the Agastyamala Hills, at an altitude of 850 m.

Relationships. Memecylon agastyamalaianum is closely allied to M. manickamii C. Murugan, Sundaresan et Jothi., but is clearly distinguished by its few-flowered, axillary, short - peduncled (to 0.5 cm long) inflorescence; acute 4-angular branchlets; terete peduncles; and fairly long pedicels. Memecylon manickamii, in contrast, bears

*Corresponding author. Tel: 91-0472-869226; Fax. 91-0472- 869646; E-mail: santhoshkumares@rediffmail.com

Botanical Bulletin of Academia Sinica, Vol. 44, 2003

Figure 1. Memecylon agastyamalaianum Santhosh, Raju et Shanavas. A, Habit; B, A flower; C, Flower buds; D, Cross section of branchlet; E, Bract; F, Calyx, view from above; G, Calyx cup with ovary, longitudinal section; H, A petal; I, Stamens, lateral and frontal view; J, A fruit.

Santhosh Kumar et al. — Memecylon agastyamalaianum, a new species from India

many-flowered terminal or subterminal long-peduncled (1-1.8 cm long) inflorescences, 4-angular peduncles, grooved branchlets, and shorter pedicels.

This species also resembles Memecylon varians Thw., an endemic species of Sri Lanka, but clearly differs in the smaller leaves with obtuse or emarginate apex, flowers with distinct pedicels, longer than the receptacle, and anthers with in size a well-developed gland. In M. varians, leaves are larger with acuminate-caudate apex, flowers with short pedicels, always much shorter than the receptacle, and anthers with or without a rudimentary gland.

Acknowledgements. The authors are grateful to the Director of the Tropical Botanic Garden and Research Institute (TBGRI), for encouragement; and to Dr. M.P. Nayar, Emeritus Scientist at TBGRI for confirming the novelty of the taxon and rendering the Latin diagnosis. We are also thankful to Dr. Kare Bremer, Institute of Botany, University of Stockholm, Sweden and to Dr. Thomas G. Lammers, University of Wisconsin, Oshkosh for reviewing the manuscript.

Literature Cited

Bremer, K. 1979. Taxonomy of Memecylon (Melastomataceae) in Ceylon. Oper. Bot. 50: 1-32.

Clarke, C.B. 1879. Memecylon in Hook. f., Flora of British India, vol. 2.L. Reeve & Co., London, pp. 553-565.

Gamble, J.S. 1919. Memecylon in Flora of the Presidency of Madras. London. Part. III, pp. 500-505.

Mabberley, D.J. 1987. The Plant Book. Cambridge University Press, Cambridge.

Murugan, C., V. Sundaresan, and G.J. Jothi. 2000. Memecylon manickamii, a new species of Melastomataceae from the Western ghats of Tamil Nadu. Kew Bull. 55: 1001.

Nayar, M.P. 1996. Hot Spots of Endemic Plants of India, Nepal and Bhutan. Tropical Botanic Garden and Research Institute, Trivandrum.

Santapau, H. and A.N. Henry. 1972. A Dictionary of the Flowering Plants in India. CSIR Publications, New Delhi, 108.