Rumex palustris, Smith, 1800

Iamonico, Duilio, Domina, Gianniantonio & Conti, Fabio, 2023, On the identity of Rumex uliginosus and the occurrence of R. dentatus in Italy (Polygonaceae), Phytotaxa 619 (1), pp. 105-110 : 106

Typification of Rumex palustris

Rumex palustris was validly published by Smith (1800: 394) in the 1 st volume of his Flora Britannica by a short diagnosis (“ RUMEX valvulis lanceolatis graniferis basi dentatis, foliis lineari-lanceolatis, verticillis distantibus”) and a detailed description; five synonyms, the habitat (“In paludosis, fossis, et ruderatis humidis”), and the provenance (“About London in several places. Dill. Curt. By Ancle dan, Norfolk. Mr. Pitchford ”) were also provided. Among the listed synonyms, those by Boccone (1697: t. 104, “ Lapanthum aquaticum luteolae folio ”), Curtis (1777 plate no. 23 of “ Rumex maritimus ”, image at https://www.biodiversitylibrary.org/item/127334#page/98/mode/1up), L’Obel (1591: 286, “ Hydrolapathum minus ”, image at https://www.biodiversitylibrary.org/item/37876#page/293/mode/1up), and Petiver (1713 t. 2, f. 7, “Gold Dock”) refer to illustrations which are part of the original material for Rumex palustris . To note that Boccone’s illustration was cited by Gussone (1826: 151) as synonym of his R. uliginosus . The citation “ Norfolk. Mr. Pitchford ” (Norfolk is a county in the East of England, Great Britain) by Smith (1800: 394) can be considered as a syntype according to the Art. 9.6 of ICN.

Smith’s Herbarium and types are preserved at LINN (see HUH Index of botanists 2013a) where we traced four specimens (nos. 464.14, 634.3, 634.5, and 634.6; images available at https://plants.jstor.org/) annotated with “ R. [“ Rumex ”] palustris H. Brit. ”. Among these, one (no. 634.5) bears one exsiccatum (no. 1 on the sheet) collected at Norfolk by Pitchford in 1781, as annotated on the bottom-left corner of the sheet. Although both the locality and the collector match Smith’s protologue, since further original material occur for Rumex palustris (the illustrations above cited), this specimen is not the holotype and it is designated in this paper as the lectotype of the name (see Art. 9.11 of ICN) having precedence over illustrations (Art. 9.12 of ICN; see also Jarvis 2007: 21–22). The specimen LINN no. 634.5 morphologically matches the original description and the current concept of Rumex palustris by showing the following characters (see e.g., Akeroyd 1993, Galasso 2018): herb with stem lacking axillary shoots; leaves cuneate at the base; whorls many-flowered; fruiting valves about 3.0‒ 3.5 mm long, at least some with tubercules and distinct teeth (each less than 2 mm long).