Cycas pranburiensis

Cycas pranburiensis is a lovely and extremely rare plant which features bright green glossy leaves growing to 4 feet long, and a trunk which can reach 10 feet tall over time. It comes from one locality, the limestone outcrops of Khao Sam Roi Yot in Pranburi province, Thailand. There, it grows in dense thickets in crevices of jagged limestone outcrops with very little soil.

Cycas pranburiensis is distinguished from all other species in the region by its short leaves with few, leathery, short and broad leaflets and short, spine-free petioles. It features rather small pollen cones with stout spreading spines on the male cone scales. Female plants feature open seed cones with long cone scales tipped with short spines.

Cycas pranburiensis has an affinity with the unusual C. lindstromii from Vietnam, and it is allied to the C. pectinata group. Known from a single locality only, this species should be regarded as threatened. It grows up to 25 leaves in its crown, slightly keeled, with opposing leaflets at 120-140°, each containing 65-105 leaflets, and brown tomentum shedding as leaf expands. Its rachis frequently ends with a short spine.