
Fairly recently, in 1976, a team of collectors discovered a previously undescribed plant in the Campanula family, on the island of Mauritius. One of the team, Ian Richardson, named it as Wahlenbergia mauritiana in 1979. But another team member, Mats Thulin concluded the species is sufficiently distinct to merit its own genus, for which he selected the term Nesocodon, which translates as “island bell” – a lovely choice.
What could make a plant so distinct that it needs its own genus (we say it is monotypic)? Being considered the only species in your genus is a statement. Thulin explained the morphological reasons in his 1980 publication (Kew Bulletin, Vol. 34, No. 4 (1980), pp. 813-814), but there is an emotional reason. Some plants are just so plainly wonderful (or have such histories) that they get their own genus, regardless as to how cladistically isolated they might be…. Welwitschia mirabilis, Franklinia alatamaha, Dionaea muscipula, Carnegia gigantea…. Nesocodon mauritianus, the Island Belle is one such plant.

Thulin’s analytical, almost disinterested publication simply ignores a fabulous reality, evident only in living specimens with fresh flowers. This plant produces copious quantities of red nectar. Red….

The nectar clings in large droplets around the base of the anthers, turning loose as rivulets when the flower is shaken.

It is truly magnificent. And a few years passed before anyone gave this observation attention. It was a mystery.
By 2006, Hansen, Beer, and Miller had published studies suggesting there are three plants on Mauritius that produce red nectar, which may be associated with visitation (and pollination) by lizards, geckos in the genus Phelsuma. That is so bizarre. (“Mauritian coloured nectar no longer a mystery: a visual signal for lizard pollinators”, Dennis M Hansen, Karin Beer, and Christine B Müller. Biol Lett. 2006 Jun 22; 2(2): 165–168. Published online 2006 Mar 1. doi: 10.1098/rsbl.2006.0458. PMCID: PMC1618895. PMID: 17148354)
Their work was followed up by a 2013 publication describing research into gecko behavior (“Coloured and Toxic Nectar: Feeding Choices of the Madagascar Giant Day Gecko, Phelsuma grandis”; Ingrid A. Minnaar Angela Köhler Cromwell Purchase Susan W. Nicolson, Ethology, the International Journal of Behavioural Biology; Volume 119(5): 417-426, May 2013 First published: 8 April 2013 https://doi.org/10.1111/eth.12079 )
Wow!
