ECOLOGY AND GENETICS OF CARPOXYLON-MACROSPERMUM H WENDL AND DRUDE (ARECACEAE), AN ENDANGERED PALM FROM VANUATU

The documented population of the rare and endangered endemic Vanuatu p alm, Carpoxylon macrospermum H. Wendl. & Drude (Arecaceae), comprises 154 reproductively mature individuals, and progressively larger number s of associated juveniles and seedlings, scattered throughout nine isl ands of the Vanuatu archipelago. Of the total, only 32 mature individu als occur naturally on three islands - Aneityum, Futuna and Tanna - in the south of the archipelago. The remainder of the population are cul tivated, primarily as single individuals, in village situations where the palm has varying degrees of traditional importance. The species is most often a subcanopy to emergent element in rainforest where it for ms scattered small colonies. Preferred habitat appears to be moist low land forest on high-fertility soils, in microclimates where drainage m ay be impeded or where high soil moisture levels are permanently maint ained. Genetic variation within the population was determined by rando m amplified polymorphic DNA (RAPD) analysis. Only at two sites - Lown' ock and Yeruareng on Tanna - of the 26 sampled in total (of which 19 p rovided usable embryos), was there any significant variation detected. This result indicates that whatever variation there is will be found in the natural populations and that most cultivated plants are apparen tly derived from a limited number of trees. For practical conservation purposes and to maintain maximum genetic variation within the existin g and future populations, propagating materials will need to be collec ted from these two sites plus any one of the other sites. In reference to population sustainability, the number of mature individuals in the known population is extremely small, and therefore the species is pre sently under considerable threat from land clearance, habitat degradat ion and genetic erosion induced by isolation and declining numbers. Co pyright (C) 1996 Elsevier Science Limited