Affiliation:
1. Department of Biotechnology, Faculty of Science and Technology, Thammasat University, Pathum Thani, Thailand
2. Protected Area Regional Office 4, Department of National Parks Wildlife and Plant Conservation, Surat Thani, Thailand
3. The Forest Herbarium (BKF), Forest Botany Division, Department of National Parks Wildlife and Plant Conservation, Bangkok, Thailand
Abstract
We describe Lasianthus ranongensis Sinbumr. & Napiroon as a new species in the genus Lasianthus. The new taxon is intensively discussed through taxonomic affinities and information on its habitat, distribution and conservation status is provided. Moreover, line drawings and stereo microscope images of important fertile organs are demonstrated. The new species is morphologically similar to L. stipularis but differs in its having flattened branches (vs. terete), leaf blade elliptic-oblong shape of 15.0–20.0 × 4.0–6.0 cm (vs. oblanceolate-oblong 12.0–16.0 × 3.0–5.5 cm), 9–12 pairs of veins (vs. 9–10 pairs), stipule 5–7 mm long, half covering cymes (vs. 10–12.5 mm long, entirely covering cymes), four or five bracts narrowly lanceolate, 2.5–3.0 mm long (vs. bracts numerous, broadly triangular, 10–15 mm), flowers with cupular calyx (vs. with campanulate calyx), corolla villous on internal surface, and six or seven lobed (vs. pubescent on internal surface and four lobed) and drupes with five pyrenes (vs. with four pyrenes). It is also similar to L. pseudo-stipularis, but from which it is obviously distinguished by its stipule half covers cymes, secondary veins have 9–12 pairs of secondary veins, cupular calyx shape, six or seven lobed corolla, and drupe with five pyrenes, whereas L. pseudo-stipularis has stipule entirely covering cymes, 7–8 pairs of secondary veins, obconic calyx, four lobed corolla, and drupe with four pyrenes.
Funder
Department of Biotechnology, Faculty of Science and Technology, Thammasat University
Subject
General Agricultural and Biological Sciences,General Biochemistry, Genetics and Molecular Biology,General Medicine,General Neuroscience
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