In: Phyton 56, Fasc. 2 (2016): S. 129-152 DOI: 10.12905/0380.phyton56(2)2016-0129

Taxonomic Revision of Pinus in Vietnam 2., New Results

By

Roman Businský

Received June 21, 2016

Key words: Pinaceae, Pinus, Pinus henryi subsp. averyanovii subsp. nova, Pinus anemophila, Pinus dalatensis, Pinus fenzeliana, Pinus latteri, Pinus wangii. – Revisions, taxa circumscription, taxonomy. – Flora of Vietnam.

Summary
Businský R. 2016. Taxonomic revision of Pinus in Vietnam 2., new results. – Phyton (Horn, Austria) 56(2): 129–152, 3 figures.

During the author’s most recent field study of Pinus in North Vietnam and within the subsequent research, several new findings have been revealed. The occurrence of P. wangii Hu & W. C. Cheng subsp. wangii was confirmed in the western part of the Cao Bang Province, this extended the range significantly. The 2014 discovery of a small population of the two-leaved hard pine on karstic hills in the Bao Lac District (Cao Bang Province) was revised, including the discovery of two new occurrences and the respective pine being classified as a new subspecies, P. henryi Mast. subsp. averyanovii Businský. The 2002 collection from the vicinity of Na Hang (Tuyen Quang Province), two later collections from the Ha Giang Province, the 1982 collection from SE Yunnan, and two populations from Guangxi known previously as Pinus taiwanensis Hayata var. damingshanensis W. C. Cheng & L. K. Fu were also identified as this subspecies. The soft pine recently discovered in the sandstone mountains Pha Luong in the Son La Province near the border of Laos, described in 2014 as P. cernua P. K. Lôc ex Aver., K. S. Nguyen & T. H. Nguyen, was studied thoroughly in the field and additionally compared with authentic samples (including the neotype material) and available data from the Chinese P. fenzeliana Hand.-Mazz., revealing the presumed identity of these taxa within the known morphological variation of the latter. For this reason, P. cernua is relegated to a synonym of P. fenzeliana. Circumstances and shortcomings associated with the redundant description and a subsequent assessment of P. cernua are discussed in detail. A unique natural site of the hard pine P. latteri Mason overlapping marginally with the area of P. fenzeliana was newly discovered on the northern slope in the Pha Luong Mountains. Information on a remarkable isolated natural population of P. latteri recently discovered by Vietnamese colleagues close to the sea coast near Nha Trang in South Vietnam is provided. An important voucher specimen of the soft pine from the east of the Saravan Province in South Laos from 2013 was identified as P. dalatensis Ferré subsp. procera Businský, which corresponds well with the oldest, but still not exactly localized, discovery of a soft pine in Indochina from 1918. The recent speculative and doubly identically created (!) combination P. dalatensis var. anemophila (Businský) Aver. (supplemented by a description compiled from two taxa) was based on certain convergent characteristics and the similar general appearance of P. anemophila Businský and P. dalatensis rather than on an assessment of diagnostic traits.