Abstract

Principal components analysis (PCA) was employed to analyse the morphological variation among 63 herbarium specimens tentatively identified as Pomatocalpa andamanicum (Hook.f.) J. J. Sm., P. koordersii (Rolfe) J. J. Sm., P. latifolium (Lindl.) J. J. Sm., P. linearifolium Seidenf., P. maculosum (Lindl.) J. J. Sm., P. marsupiale (Kraenzl.) J. J. Sm., P. naevatum J. J. Sm., or P. siamense (Rolfe ex Downie) Summerh. Thirty-seven quantitative and 5 binary characters were included in the analyses. Taxa were delimited according to the observed clustering of specimens in the PCA plots, diagnostic characters were identified, and the correct nomenclature was established through examination of type material. Four species could be recognized viz, P. diffusum Breda (syn. P. latifolium), P. fuscum (Lindl.) J. J. Sm. (syn. P. latifolium), P. marsupiale (syn. P. koordersii) and P. maculosum. For the latter species, two subspecies could be recognized, viz P. maculosum (Lindl.) J. J. Sm. subsp. maculosum (syn. P. maculosum, P. naevatum p.p.) and P. maculosum (Lindl.) J. J. Sm. subsp. andamanicum (Hook.f.) S. Watthana (syn. P. andamanicum, P. linearifolium, P. siamense, P. naevatum p.p.). An identification key and a taxonomic synopsis are provided.

中文摘要

用主群體分析方法(PCA)來檢視63份暫定為P. linearifolium Seidenf., P. maculosum (Lindl.) J. J. Sm., P. marsupiale (Kraenzl.) J. J. Sm., P. naevatum J. J. Sm., or P. siamense (Rolfe ex Downie) Summerh.的臘葉標本。分析項目包括37個定量及5個二元的特徵。於主群體分析結果中，依觀測到的標本群團界定分類群並確認識別特徵。同時經由模式標本檢驗建立正確之學名。共認定有四個種，也就是P. diffusum Breda (P. latifolium為其同物異名)，P. fuscum (Lindl.) J. J. Sm. (P. latifolium 為其同物異名)，P. marsupiale (P. koordersii為其同物異名) 及P. maculosum。而最後一種可再分為兩亞種，也就是 P. maculosum (Lindl.) J. J. Sm. subsp. maculosum (P. maculosum, P. naevatyum p.p.為其同物異名)及P. maculosum (Lindl.) J. J. Sm. subsp. andamanicum (Hook.f.) Watthana (P. andamanicum, P. linearifolium, P. siamense, P. naevatum p.p.為其同物異名)。本文並提供檢索表及分類綱要。

Keyword: Orchidaceae, Pomatocalpa, Taxonomy, Principal component analysis, Flora of Southeast Asia.