Persicaria dichotoma ( Blume 1826: 529 ) Masamune (1954: 82) var. angustissima S. F. Chen et B. Li, 2015

Chen, Shaofeng & Li, Bo, 2015, Two new combinations in Persicaria sect. Echinocaulon (Polygonaceae: Persicarieae), Phytotaxa 224 (2), pp. 196-198 : 197

Persicaria dichotoma ( Blume 1826: 529) Masamune (1954: 82) var. angustissima S. F. Chen et B. Li , comb. nov.

Bas.: Polygonum pedunculare Wallich ex Meisner var. angustissimum Hooker (1886: 48) . ≡ Polygonum dichotomum Blume var. angustissimum (Hooker) Park (1988: 75) .

Type (lectotype, designated here):— INDIA. s.l., s.d., Wight 2781 (lectotype K-000830518!, image avaiable at http://apps.kew.org/herbcat/ getImage.do?imageBarcode= K 000830518).

Distribution: — Persicaria dichotoma var. angustissima is known only from India, mainly occurs in Nilgiri mountains which spanning the states of Tamil Nadu and Kerala in Southern India.

Note: — Hooker (1886: 48) listed 4 collections which are syntypes according to the art. 9.5 of ICN ( McNeill et al. 2012). Park (1988) listed all these specimens without specifying which of them is the lectotype. We was able to trace only one of the four collection cited in the protologue, which is preserved at K (code 000830518, Wight’s collection no. 2781). Although the date of colleciton is lacking, the number on the specimen (2871) matches that occuring in the protologue, so we consider this exsiccatum as part of the original material, and designate it as the leectotype of the name.

From the taxonomical point of view, we accept to recognize the Hooker’s taxon at variety level (also according to Park 1998), which differs from the nominal one in having sessile to subsessile, linear lanceolate to lanceolate leaves with somewhat attenuate bases.