Alyxia

Alyxia is a Australasian genus with 106 species from the Dogbane family (Apocynaceae)

This genus occurs in China, the Himalayas, SE Asia, Malaysia, Australia, New Caledonia and the Pacific Islands. There are 14 species in Australia, 21 in new Caledonia and 7 in the other Pacific Islands, including Hawaii.

The genus consists of shrubs, climbers or scramblers (a plant with long stems, often with thorns to help it support itself as it climbs through shrubs).

The leaves are opposite or in whorls of 3 to 7. There are colleters present in the leaf axils, i.e. a group or tuft of mucilaginous secretory hairs.

The inflorescence is axillary or terminal with solitary flowers or simple cymes. Flowers consist of 5 petals and 5 sepals. The flowers have a slender tube which expands abruptly. The stamens have short filamens and are inserted in the upper half of the corolla.

The fruit is a pair of drupes, originating from each flower.

Alyxia stellata and Alyxia tisserantii are variable species and need of further study.

Species

• Alyxia buxifolia : Dysentery Bush
• Alyxia oleifolia : (occurs in Borneo; leaves in whorls od 3; flowers fleshy)
• Alyxia oliviformis : Maile (endemic to Hawaii)
• Alyxia reinwardtii: (occurs in Borneo; leaves in whorls of 3 to 5; flowers non-fleshy).
• Alyxia ruscifolia : Chainfruit, Sea Box
• Alyxia angustifolia, Alyxia bracteolosa, Alyxia celebica, Alyxia daphnoides, Alyxia evansii, Alyxia fascicularis, Alyxia flavescens, Alyxia floribunda, Alyxia ganophylla, Alyxia globosa, Alyxia graciliflora, Alyxia ilicifolia, Alyxia ilicifolia ssp. magnifolia, Alyxia insularis, Alyxia kwalotabaa, Alyxia lackii, Alyxia levinei, Alyxia linearifolia, Alyxia longiloba, Alyxia manusiana, Alyxia marginata, Alyxia menglungensis, Alyxia minutiflora, Alyxia mucronata, Alyxia muguma, Alyxia obtusifolia (= Alyxia spicata), Alyxia odorata, Alyxia papuana, Alyxia poyaensis, Alyxia quadrata, Alyxia racemosa, Alyxia ruscifolia ssp. major, Alyxia ruscifolia ssp. ruscifolia, Alyxia scabrida, Alyxia schlechteri, Alyxia siamensis, Alyxia sinensis, Alyxia solomonensis, Alyxia stellata, Alyxia taiwanensis, Alyxia thailandica, Alyxia tisserantii, Alyxia tropica, Alyxia uniflora, Alyxia veillonii, Alyxia vera, Alyxia villilimba.

Reference

• MIDDLETON, D.J. (2000). Revision of Alyxia (Apocynaceae). Part 1: Asia and Malesia. Blumea 45: 1–146
• MIDDLETON, D.J. (2001). Revision of Alyxia (Apocynaceae). Part 2: Australia and Pacific Islands. Blumea 46