Exacum sessile

Genus Exacum or in sinhalese “Binara” are attractive wild flower types and is best known for its dazzling blue and belongs to the family Gentianaceae.

The name Exacum is derived from its property of expelling pollens through the apical pores of anthers.

There are 8 Exacum species found in Sri Lanka, out of those species, 5 are protected under the Fauna and Flora Protection Ordinance and two are critically endangered.

Exacum sessile is one of the two critically endangered Binara species in Sri Lanka.

There is a fascinating story behind the describing this plant and it begins way back in sixteen seventies.

German-born physician and botanist Paul Hermann arrived the island as a Ship's Medical Officer for Dutch East India Company in 1672. During his stay, he collected many Ceylonese plants and deposited in Botanical garden of Leiden where he later appointed as the director. In 1753, 58 years after Paul Hermann’s death Carl Linnaeus described Exacum sessile, using a specimen from Hermann's original Ceylon collection. It was published on his book “Species plantarum”. Exacum sessile is the type species for Genus Exacum.

It is an annual herb with a shallow rootstock, which grows up to 1 feet. This species can be distinguished from other Exacum species by its sessile leaves and dorsally flat calyx lobes.

Exacum sessile can be found on wet rocks, in wet open grasslands and moist places up to 1200 meters above sea level. Mainly found in the wet zone. It also occurs in south India.

Habitat loss is the greatest threat to this species, therefor Exacum sessile is listed under the critically endangered category in 2020 National Redlist.

It is our duty to protect this species for tomorrow……