Geography and distribution
Abutilon ranadei is restricted to the North Western Ghats of Maharashtra State in western India, where it occurs at 600-1,200 m above sea level, between 16.4-19 degreesN and 72-74 degrees E on the crest line of the Western Ghats. It is restricted to highly fragmented populations in ten localities, in moist deciduous forest on hill slopes, especially in thickets or stands of Strobilanthes callosa (known locally as 'karvi').
Description
Overview: Abutilon ranadei is an undershrub, measuring 2.5-3.5 m high. The vegetative plant parts bear star-shaped hairs.
Leaves: The leaves are ovate to rounded-ovate, with tips that taper to a point, heart-shaped bases and scalloped to toothed margins.
Flowers: The solitary flowers are about 2.5 cm in diameter. The calyx is bell-shaped, with lobes free up to the middle, and is covered with glands and star-shaped hairs. The corolla is bell-shaped with pale purple petals with orange-yellow tips. The petals are twice as long as the calyx. The staminal column is 2-3.5 cm long and is hairless with purple lines. The filaments are white with a reddish base, 3-5 mm long, and have dumbbell-shaped glandular hairs in the upper part. The anther lobes are kidney-shaped and are initially green, turning dark rose at maturity and brownish-violet at dehiscence. There are five styles, which are up to 7 mm long and sparsely hairy. The five carpels have a sharp point and are densely hairy throughout.
Fruits: The fruits are schizocarpic (split into a number of seed-containing parts).
Flowering and pollination
Flowering begins in early November and continues until the end of March.
During the pollination stage the glandular hairs on the calyx tube emit a strong odour and secrete nectar from the nectaries, which are located at the base of the petals. These attract insects such as honey bees ( Apis mellifera ) and certain fast-moving Dipteran flies, which are most likely to be the pollinators.
Detailed pollination studies, however, are urgently needed.
Threats and conservation
Anthropogenic threats include the periodic harvesting of firewood from the edges of the forests where it occurs, forest fires, and the collection of Strobilanthes callosa stems for house-building and agricultural practices, which disturb the habitat of this dwindling species.
A. ranadei also faces natural pests such as tropical red spider mites, striped mealy bugs, cabbage semi-loopers, aphids, purple scale insects, leaf miners and snails. Amongst the known natural pests, mealy bugs present the most common threat.
Cultivation and re-introduction
Although Critically Endangered in the wild, Abutilon ranadei can be propagated by seed and vegetative propagation under nursery conditions. However, the percentage of seeds germinating is very low. Vegetative propagation methods such as air layering are more successful, and this method is used at the Naoroji Godrej Centre for Plant Research (NGCPR, Shindewadi), Satara District, Maharashtra State of India. A. ranadei plants produced by air layering are then planted out into their natural habitat in Maharashtra.
Uses
Abutilon ranadei is an attractive plant with showy, nectar-producing flowers and could be cultivated as an ornamental.
This species at Kew
Pressed and dried specimens of Abutilon ranadei are held in the Herbarium at Kew, where they are available by appointment to researchers from around the world. The details, including images, of some of these specimens can be seen online in the Herbarium Catalogue.