Kiaerskov's lidflower  (Calyptranthes kiaerskovii)

Kiaerskov’s lidflower is classified as Critically Endangered (CR) on the IUCN Red List (1).

Kiaerskov’s lidflower (Calyptranthes kiaerskovii) is a small, evergreen tree known only from Virgin Gorda in the British Virgin Islands and possibly from a single surviving individual in Puerto Rico (1) (2).

Very little information is available on Kiaerskov’s lidflower, but like other members of the Myrtaceae family it has leathery leaves which grow in opposite pairs, and the flowers are likely to grow in small clusters, known as an inflorescence (3) (4). The flowers of Calyptranthes species generally have up to five small petals, and the fruit is in the form of a fleshy berry that contains one to two seeds (3) (4) (5).

The largest remaining population of Kiaerskov’s lidflower occurs within Gorda Peak National Park, on Virgin Gorda, one of the British Virgin Islands (1) (2) (6). This rare plant has also been recorded at three sites in Puerto Rico, each containing just a single individual, but only one of these may still survive (1) (2).

Kiaerskov’s lidflower formerly occurred on the Puerto Rican island of Vieques and on the island of Tortola in the British Virgin Islands. However, it is now believed to be extinct at both these locations (1) (2).

Kiaerskov’s lidflower occurs in moist forest, as well as in wetter areas of dry forest (1) (2) (6).

Very little is currently known about the biology of Kiaerskov’s lidflower. On Virgin Gorda, it has been seen flowering and fruiting between November and December, towards the end of the rainy season. However, no seedlings have been observed, suggesting that either the seeds are not germinating or the seedlings do not survive the dry season between March and May (1).

The population of Kiaerskov’s lidflower on Vieques Island was destroyed by the construction of a helipad (1) (2), while in Puerto Rico the main threat to this species is likely to have come from habitat loss due to development (1). Kiaerskov’s lidflower has not been recorded on Tortola for some time (1) (2), but the reasons for its demise there are unclear.

The largest surviving population of Kiaerskov’s lidflower, on Virgin Gorda, is thought to contain just 25 mature individuals, with a further mature tree around 100 metres away from the main group. In addition to the single individual thought to remain in Puerto Rico, this gives a total population of only around 27 known individuals, making Kiaerskov’s lidflower a highly endangered species (1). Although the Virgin Gorda population occurs within a protected area, the trees are near trails and so may be at risk from walkers, and fire is also a potential threat (1).

On Virgin Gorda, Kiaerskov’s lidflower occurs entirely within Gorda Peak National Park, a protected area with reasonably well respected boundaries (1). A Darwin Initiative Project has undertaken conservation work in the British Virgin Islands, and recommendations for preserving the islands’ plant species include seed collection, monitoring programmes and introducing plants into cultivation. It will also be important to raise public awareness about the value of the region’s unique flora and its conservation (6).

ARKive is supported by OTEP, a joint programme of funding from the UK FCO and DFID which provides support to address priority environmental issues in the Overseas Territories, and Defra

Find out more about conservation in the British Virgin Islands and other UK Overseas Territories:

• UK Overseas Territories Conservation Forum - British Virgin Islands:
  http://www.ukotcf.org/territories/bvi.htm
• RSPB: The UK Overseas Territories - The UK’s hidden natural treasures:
  http://www.rspb.org.uk/ourwork/projects/details.asp?id=tcm:9-200664
• Oldfield, S., Procter, D. and Fleming, L.V. (1999) Biodiversity: the UK Overseas Territories. Joint Nature Conservation Committee, Peterborough. Available at:
  http://www.jncc.gov.uk/page-3045