Novitates neocaledonicae. XIII. Taxonomy and nomenclature of the genus Xyris (Xyridaceae, Poales) in New Caledonia, with description of a new species Author Morel, Jérémie AMAP, Université Montpellier, IRD, CIRAD, CNRS, INRAE, F- 34000 Montpellier (France). Author Munzinger, Jérôme AMAP, Université Montpellier, IRD, CIRAD, CNRS, INRAE, F- 34000 Montpellier (France). text Phytotaxa 2021 2021-05-25 502 3 219 229 http://dx.doi.org/10.11646/phytotaxa.502.3.1 journal article 10.11646/phytotaxa.502.3.1 1179-3163 5425077 Xyris neocaledonica Rendle, Journ. Bot. 1899 , 507. Type:— NEW CALEDONIA . Mt. Mon [=Mou], E. Vieillard 1408 , ( lectotype , designated here: BM [BM000990765] (image seen); isolectotype: P [P01766970]!) . Nomenclatural remarks :—The protologue of Rendle (1899: 507) indicates “Hab. New Caledonia . Dry ferruginous soil, 400 metres; Pancher no. 411. Mt. Mon [=Mou]; Vieillard 1408 in herb. Hance no. 17,369 ” , thus implicitly designing a syntype ( Turland et al. 2018 ; Article 40, Note 1). The two collections cited were mounted on the same sheet at BM, where Rendle was working, but clearly identified as distinct, and each having a barcode [BM000990764, BM000990765]. Hance has never made a collection in New Caledonia ( Morat 2010 ), so he received collection 1408 from Vieillard, and gave it his own number 17,369. This Vieillard collection [BM000990765] is in good condition, with flowers and bears the locality of the protologue, and this is selected as the lectotype . Then, it is usual for Pancher and Vieillard to encounter the same label numbers assigned to different gatherings ( MacKee and MacKee 1981 ; Hopkins and Bradford 2009 ). Six duplicates of Vieillard 1408 were found at P, five collected from “M’bée mountains” in 1855-1860 [P01766975, P01760201, P01760200, P01760183, P0176697] and one from “Mont Mou”, 1861-1867 [P01766970]. Therefore, only this latest specimen, whose locality conforms to the protologue, can be considered as an iso-lectotype.