Typification of binomials in Xyris section Nematopus (Xyridaceae) published by L. A. Nilsson Author Wanderley, Maria das Gracas Lapa Instituto de Botanica, Sao Paulo, Brazil gracaw@me.com text PhytoKeys 2017 2017-06-05 80 65 76 http://dx.doi.org/10.3897/phytokeys.80.12348 journal article http://dx.doi.org/10.3897/phytokeys.80.12348 1314-2003-80-65 FFE2FF84FF98FFA5FFB4FFAFFFFFFFBA 816394 12 . Xyris seubertii L.A.Nilsson, Kongl. Svenska Vetenskap.-Akad. Handl. 24(14): 51. 1892. Type . Guyana : "British Guiana", Rich. Schomburgk 897 (in herb. Berol.) ( holotype : B! [B10 0242218]; isotype: K! [K000308887]). In his species description, Nilsson (1892) cited the collection Schomburgk 897 , originating from British Guiana , undated, and deposited in the B herbarium. The unicate of this collection in B (B10 0242218) was examined, and is compatible with the protologue. Smith and Downs (1968) cited this sheet (B10 0242218) as "type" , thus identifying it as the holotype , which has two plants with the typical characteristics of Xyris seubertii , and the label indicates the location and the date ( October 1842 ), as quoted in the protologue. Illustrations attached to the holotype sheet show characteristic features of the species, with a drawing of the central placenta and sepals with a thickly pilose carina and acute apex. However, in addition to these illustrations, there is an annotation signed by Seubert that indicates the species as Xyris fontanesiana Kunth, now considered as a synonym of Xyris anceps Lam. ( Xyris section Xyris ), which has a marginal placenta and is very different from X. seubertii ( Xyris section Nematopus ). An isotype is deposited at K (K000308887), with an annotation giving its origin from Guiana , and with indications of having previously been separated from another specimen. Another sheet at K (K000308888), also of Xyris seubertii , has the locality information "Roraima Expedition, British Guiana , Monte Roraima". The collector is not mentioned, but the number 257 given on the label makes clear that it does not belong to the type collection.