Consultation > Par auteur > Le Thu

Keteleeria Carrière is a small genus of the family Pinaceae which comprises 3 species distributed in southern China (all species), Vietnam (two species) and Laos (two species). The objective of the present study was to revise species of Keteleeria in Vietnam and determine their geographical distribution. The results of a traditional morphological analysis, based on 47 new collections made between 1995 and 2015 (previous collections have been studied by N. T. Hiep and J. E. Vidal, 1996), confirms that there are two native species in Vietnam, K. evelyniana Mast. and K. davidiana (Bertr.) Beiss., and one which is known only from cultivation, Keteleeria sp., whose provenance is unknown. K. evelyniana differs from K. davidiana by its seed scales which are distinctly longer than wide (widest point usually below the middle) and by its more extensive distribution in non-limestone areas of north western Vietnam along the border region with Laos (vs. seed scales as long as or slightly longer than wide, with the widest point at the middle, and distribution very restricted in limestone areas of north eastern Vietnam). Keteleeria sp. differs from the above-mentioned 3 species by having leaves on cone-bearing branchlets longer than 5.5 cm (vs. shorter than 4.5 cm), by the opened seed cones narrower and seed scales shape , less than 5 cm (vs. wider than 6.5 cm) and especially by the particular arrangement of leaves on 1st year branchlets of adult trees: leaves on upper side of branchlets early and strongly ascending, forming two opposite, adaxial to adaxial rows, leaves on lateral sides of branchlets spreading in two more less remote sets, and the absence of leaves on the lower side of branchlets (vs. leaves ± pectinately or radially arranged).