Thailand Mann Plum Yew (Cephalotaxus mannii subsp. thailandensis)
Cephalotaxus mannii subsp. thailandensis: Rare Thai Plum Yew Subspecies
The humid, high-altitude ridges of northern Thailand provide a sanctuary for Cephalotaxus mannii subsp. thailandensis, an extremely rare gymnosperm. This conifer grows under the canopy of montane evergreen forests, requiring specific microclimatic conditions. Due to habitat fragmentation, its natural populations remain highly isolated.
Taxonomy
- ∟ царство Plantae
- ∟ division Tracheophytes
- ∟ subdivision Spermatophytes (Seed plants)
- ∟ superclass Gymnospermae
- ∟ division Pinophyta
- ∟ subclass Cupressidae
- ∟ order Cupressales (Cypresses and junipers)
- ∟ family Cephalotaxaceae (Plum-yews family)
- ∟ genus Cephalotaxus (Plum yew)
- ∟ species Cephalotaxus mannii (Mann's plum yew)
- ∟ subspecies Cephalotaxus mannii subsp. thailandensis (Thailand Mann Plum Yew)
Morphology
This evergreen tree typically reaches a height of fifteen to twenty meters. The trunk is supported by a smooth, grey-brown bark that becomes slightly fissured as the specimen ages. The leaves are flat, linear-lanceolate, and measure up to eight centimeters in length, showing two distinct silver stomatal bands underneath.
Its reproductive morphology features specific characteristics:
- Pollen cones: Arranged in small, capitate clusters along the leaf axils.
- Seed structures: Borne on short stalks, ripening into large, egg-shaped seeds.
- Aril: Fleshy, reddish-purple outer envelope surrounding the hard seed coat.
Applications
This taxon holds immense value for botanical research and conservation programs. Biochemists study its foliage for unique diterpenoids and alkaloids with potential pharmacological applications. The wood, although durable and fine-textured, is not harvested commercially due to the plant's rarity.
Interesting facts
This subspecies was discovered in the mountain ranges of Chiang Mai province, particularly around Doi Inthanon. The high altitude and persistent cloud cover of these peaks provide the constant moisture necessary for its survival. Local conservation initiatives focus on protecting its remaining wild populations from agricultural encroachment.
Geography of distribution
- Thailand
Sources
- POWO: Plants of the World Online
- WFO: World Flora Online
- GBIF: Global Biodiversity Information Facility