Ceropegia mahajanii (Kambale & S.R.Yadav) Bruyns

Kambale, S.S., Surveswaran, S. & Yadav, S.R. 2014. Two new species of Brachystelma Sims (Apocynaceae: Asclepiadoideae-Ceropegieae) from the Western Ghats of India. Kew Bulletin 69: 9493. DOI https://doi.org/10.1007/s12225-014-9493-1

Type

Type: India, Tamil Nadu, Nilgiri Distr., Ebbanad, Kambale & Yadav SSK 49 (holotype CAL!; isotypes K!, MH!, SUK!).

Morphology General Habit

Perennial erect tuberous herb

Morphology Roots

Rootstock subglobose-discoid, tuber 10 – 40 mm in diam.

Morphology Stem

Stem usually one, rarely branched above the ground, erect, 4 – 9 cm, internodes 0.5 – 3.0 cm long, 1 – 2 mm in diam., puberulous, hairs minute, simple, translucent

Morphology Leaves

Leaves linear-lanceolate, acute at apex, sessile, 18 – 42 × 0.8 – 1.6 mm, drooping, fleshy, opposite, decussate, ciliolate along margin and midrib beneath, glabrous otherwise

Morphology Reproductive morphology Inflorescences

Inflorescence extra-axillary

Morphology Reproductive morphology Flowers

Flowers 1 – 8 at each node, flowers 1 – 2 in axils of each bract, buds facing upwards, flowers drooping; floral bract solitary, 1 × 2 mm, persistent, subulate, hairy at apex; bracteoles 0.5 × 0.1 mm, 1 – 2 per flower, purplish, linear

Morphology Reproductive morphology Flowers Pedicel

Pedicel 3.0 – 5.0 mm long, terete, pubescent

Morphology Reproductive morphology Flowers Calyx

Calyx free, sepals subulate, 1.2 (1.6) × 0.4 – 0.6 mm at base, acute, puberulous on abaxial surface, glabrous otherwise

Morphology Reproductive morphology Flowers Corolla

Corolla stellate, drooping, c. 3 7 – 7 mm long, c. 7.5 – 8 (14) mm in diam., glabrous outside, corolla tube saucer shaped, c. 3 mm in diam., 1 – 1.2 (1.4) mm deep, abaxially greenish yellow spotted with purple, adaxially yellowish-green, glabrous within; corolla lobes 2 (5) – 2.5 (5.6) mm long, spreading, rarely reflexed, revolute along margins, glabrous, yellow at upper half, green at lower half, lanceolate, acute at apex, broad at base

Morphology Reproductive morphology Flowers Corona

Corona biseriate, staminal and interstaminal parts fused to a cup shaped structure; interstaminal corona 2 × 2 mm, of 5 lobes, lobes undulate, much taller than gynostegium, greenish-yellow spotted purple outside and within, glabrous; staminal corona lobes linear, triangular at tip, procumbent on stigma

Morphology Reproductive morphology Flowers Gynostegium

Gynostegiumsubsessile, anther sacs yellow, stylar head white, flat

Morphology Reproductive morphology Flowers Pollinarium

Pollinarium: pollinia yellow with pellucid margin, 0.2 × 0.2 mm, reniform, attached to corpusculum by short caudicle; corpusculum brown

Morphology Reproductive morphology Fruits

Mericarps paired, fusiform, unequal, 5 – 7.5 cm long, yellowish green, faint purple at maturity; fruiting pedicels straight, c. 1.5 cm long

Morphology Reproductive morphology Seeds

Seeds 7 – 9 × 1 – 1.5 mm, comose, narrowly elliptic, blackish brown at centre, margin winged, yellow; coma c. 1.5 cm long, silky white

Note

Brachystelmamahajanii is similar to B. ciliatum (Ramakrishna et al. 1995) but differs in its axillary 1 – 8 stellate drooping flowers per node, corolla lobes glabrous, interstaminal corona raised above the gynostegium and with undulate to entire lobes (vs 2 – 4-flowered umbel inflorescence, corolla lobes with tufts of vibratile hairs at the tip, interstaminal corona equal to gynostegium and with orbicular lobes in B. ciliatum). The specific epithet honours a botanist and a teacher, Mr S. D. Mahajan, Gokhale College, Kolhapur for his contribution to the conservation of plant diversity of Northern Western Ghats. In addition to morphological similarities with Brachystelmaciliatum, B. mahajanii is also apparently similar to B. nanum (Schltr.) N. E. Br. from South Africa. However in contrast to morphological similarities these two species are phylogenetically unrelated. The morphological similarity is due to independent evolution of similar, convergent characters (Fig. 1).

Distribution

India: Tamil Nadu; Nilgiri Distr., Ebbanad village.

Ecology

Brachystelmamahajanii grows along the eastward slopes of the Nilgiris in soils accumulated on rocks at an altitude of c.1792 m.

Conservation

Brachystelmamahajanii is so far known from the type locality only. About 100 individuals were located. According to IUCN criteria, the species falls under the category Data Deficient (DD) (IUCN 2001, 2010).

Phenology

Flowering March – May; fruiting April – June. Under cultivation the plant flowered before leaves developed (hysteranthous) in March 2013 and with leaves (synanthous) in July 2013. In the field, we collected the plants flowering and fruiting in May 2013.