Snowdonia hawkweed  (Hieracium snowdoniense)

Asexually: of asexual reproduction: reproduction that does not involve the formation of sex cells ('gametes'). In many species, asexual reproduction can occur by fission (or in plants 'vegetative reproduction'); part of the organism breaks away and develops into a separate individual. Some animals, including vertebrates can develop from unfertilised eggs, this process, known as parthenogenesis gives rise to offspring that are genetically identical to the parent.
Endemic: a species or taxonomic group that is only found in one particular country or geographic area.
Ex-situ: measures to conserve a species or habitat that occur outside of the natural range of the species. E.g. in zoos or botanical gardens.
Perennial: plants that live for at least three seasons; after an initial period they produce flowers once a year.
Whorl: in animals, the spiral or convolutions in the shell of a snail. In plants, a set of leaves, flowers, or branches that spring from a stem at the same point and encircle it.

1. National Biodiversity Network Species Dictionary (February 2001)
   http://www.nhm.ac.uk/nbn
   
2. Rich, T. C. G (2002) Extinct plant rediscovered in Wales. Biodiversity News. 21: 4.
   
3. Rich, T.C.G. & Hand, S.O. (2003) Conservation of Britain’s biodiversity: Hieracium snowdoniense (Asteraceae), Snowdonia Hawkweed. Watsonia (in press).
   
4. Wiggington, M. J. (1999) British Red Data Books 1: Vascular Plants. 3rd Edition. Joint Nature Conservation Committee, Peterborough.
   
5. Akeroyd, J. (2002) Lost plant of the Welsh mountains reappears. Plant Talk. 31:18.