Richea scoparia

Taisha is again the author. She writes:

Today’s image is of Richea scoparia or the honey richea. It is sometimes called the kerosene plant due to the fragrance when the foliage is crushed. This photo was taken by Rotuli@Flickr in mid-December of 2013. Thanks Rotuli!

The ericaceous Richea scoparia is one of nine Tasmanian endemic species in the genus. The two other species in the genus, Richea continentis and Richea victoriana, are endemic to southeastern mainland Australia, where they are found in alpine bogs or high-elevation wet areas. The subject of today’s BPotD, Richea scoparia is also a highland dweller with a preference for rich and boggy soils. This woody shrub is slow-growing, eventually achieving a height of around 1.5 meters. The stiff, palm-like leaves are narrow and pointed, while the flowers of Richea scoparia are arranged in a spike. White, red, pink, or yellow petals are fused to form a calyptrum (i.e., a cap of fused petals).

The nectar-filled calyptra of honey richea are often removed by visiting lizards in search of a sweet reward. This seemingly-destructive act actually provides a reproductive advantage for the species. Mats Olsson and colleagues from the University of Sydney and University of Gothenburg conducted a study on the interaction and coevolution between Richea scoparia and the lizard species Niveoscinus microlepidotus (or snow skink) on Mount Wellington, Tasmania. In seeking the nectar by removing the calyptra, the reptiles expose the plant’s reproductive organs–much improving rates of pollination and outcrossing compared to those flowers with intact calyptra (as observed by Olsson et al.). Although the reptiles don’t carry pollen themselves, they do facilitate pollination through other vectors such as insects and wind. Intriguingly, the removal of the calyptra was shown to increase the number of seeds dispersed by the honey richea. Plants in their study with lizard-removed calyptra released seeds successfully in 87% of the flowers, compared with 0% in those flowers with intact calyptra (see: Olsson, et al. Lizards as a plant’s ‘hired help’: letting pollinators in and seeds out. (PDF) Biological Journal of the Linnean Society. 71:191-202).

Richea scoparia

5 responses to “Richea scoparia”

  1. Claire B.

    I love how animals and plants seem to have evolved ways to help each other. It’s a beautiful thing!

  2. Nadia

    Very unusual plant in Erica family, never heard about it. Thank you

  3. Elizabeth Revell

    As soon as I saw this picture I thought “Dracophyllum”. But Draco is in the Epacridaceae, not Ericaceae, so I got out my little Tasmanian plant book, and it puts Richea into the Epacridaceae, too.
    Has it all been revised?
    Incidentally, one of our NZ Draco species has been known as Kerosene plant, too, because of its usefulness to early bush workers in starting their campfires. Something more to it than just smell, perhaps?

  4. Daniel Mosquin

    Elizabeth, we use the Angiosperm Phylogeny Group classification system, and Epacridaceae was subsumed into Ericaceae in their system. The epacrids are a relatively recent lineage in the family, if I understand what I am looking at on that page.

  5. Pip Biagi

    Please can someone tell me the size of a Richea Scoparia seed?
    Thank you.

Leave a Reply