(3151) Proposal to conserve the name Lantana undulata ( Verbenaceae ) with a conserved type

(3151) Lantana undulata Schrank in Denkschr. Königl.-Baier. Bot. Ges. Regensburg 2: 56. 1822 [Angiosp.: Verben.], nom. cons. prop. Typus: Brazil, [Bahia, Ilhéus,] [1835–1837?,] [Luschnath, Martius Herb. Fl. Bras. No. 1031] (M barcode M-0111631 [image!]; isotypi: BM barcode BM000992649 [image!], BR barcodes BR0000005504619, BR0000005504633, BR0000005504947, BR0000005504985 & BR0000005504305 [left-hand specimen] [images!], G barcodes G00366440 & G00366434 [images!], K barcode K000470739 [image!], M barcode M-0111629 [image!], NY barcode 00214337 [image!], P barcode P00713631 [image!], S No. S04-2479 [image!]), typ. cons. prop. Lantana undulata Schrank (in Denkschr. Königl.-Baier. Bot. Ges. Regensburg 2: 56. 1822) was described based on material collected by Martius in Brazil and maintained in the Royal Botanic Garden in Munich in a heated greenhouse. The protologue (Schrank, l.c.) does not cite a collection or collector number, nor a specific locality. The species was characterized by having “foliis oppositis, ovato-lanceolatis, scabris, basi in petiolum cuneatis; spicis semiglobosis; bracteis tubo, pedunculis folio brevioribus; caule inermi, pubescente”. Additionally, Schrank emphasized that the inflorescences of L. undulata are capituliform, the flowers are white, with a yellow throat that fades with time, and the lower lip is very delicate and finely undulate. In a comprehensive taxonomic treatment of Verbenaceae, Schauer (in Candolle, Prodr. 11: 606. 1847) modified the original circumscription of Lantana undulata, characterizing it by having “[…] pedunculis axillaribus geminis singulisve folium subaequantibus, spicis oblongis valde elongandis et relaxandis, bracteis squarrosis membranaceis pallidis reclinatis undulatis ciliatis, infimis majoribus subrotundo-ovatis, superis oblongis basi attenuatis cuspidatis inflexis; corollae labio inferiori porrecto”. The following specimens were cited: “Salzm.! exs. n. 429, Blanchet! exs. n. 218, 631, 2365 et 3137, Luschn.! in Mart. herb. fl. bras. n. 1031! Sell.! Khotzky!” from the province of Bahia; “Guillem.! n. 600” from the province of Sebastianopolis in Ilha-Princesa; and “Cham.!” from S. Catharinae. Subsequently, Schauer (in Martius, Fl. Bras. 9: 263–264. 1851) provided a description of Lantana undulata that closely followed his 1847 treatment, accompanied by an illustration (t. 44, fig. II). This plate depicts inflorescences arranged in pairs in each leaf axil, with peduncles exceeding the subtending leaves, cylindrical spikes, and drupes with two pyrenes. Schauer (l.c. 1851) also described a new variety, L. undulata var. grandiflora, which was based on the specimen Guillemin no. 600, distinguished by its corollas with tubes more than twice as long as the subtending bract. Following the circumscription of Schauer (l.c. 1847, l.c. 1851), the name Lantana undulata became firmly associated with a plant endemic to the Brazilian Atlantic Forest, occurring mainly in Restinga (coastal vegetation) but also in seasonally deciduous forest, and characterized by having two inflorescences per leaf axil, peduncles exceeding the subtending leaves, spikes elongating up to 12 cm in fruiting, laxly arranged flowers, white corollas with a yellow throat, and vinaceous drupes with a succulent mesocarp (e.g., Silva, Redelim. Revis. Gên. Lantana Bras. [Ph.D. Thesis, Univ. São Paulo]: 132–135. 1999; Salimena in Melo & al., Fl. Faner. Ilha Cardoso, São Paulo 7: 7–26. 2000; Silva & Lima in Sitientibus, Sér. Ci. Biol. 12: 264–267. 2012; Cardoso & al. in Phytotaxa 484: 19–20. 2021a; Silva & al. in Flora & Funga do Brasil. 2026, accessed 6 Feb 2026). Because Schrank (l.c.) did not explicitly cite any original material, the specimen “Luschn. in Mart. herb. fl. bras. n. 1031”, mentioned by Schauer (l.c. 1847), came to be interpreted as the type of L. undulata. Moldenke, a major twentieth-century authority on Verbenaceae, annotated duplicates at BR and S as “cotype”, and Silva (l.c. 1999) assigned “holotype” status to a duplicate at M. However, the circumscription of Lantana undulata adopted since Schauer (l.c. 1847) is in clear conflict with the protologue, particularly regarding the length of the inflorescence peduncles and the shape of the spikes (Schrank, l.c.). Examination of the protologue and specimens deposited at M revealed original material (M-0165314) that fully agrees with the protologue and corresponds to the species concept expressed therein. This specimen exhibits semiglobose inflorescences and peduncles shorter than the leaves, as well as the remaining features of the original description, including unarmed branches, petiolate, ovate-lanceolate leaves cuneate at base, and an adaxial surface that is rough due to appressed, non-glandular trichomes, resulting in a strigose or scabrid indumentum (Schrank, l.c.). It is the only original material located; its label indicates “in Brasilia” and cultivation in the “hort. bot. Monac. | 1820”. Accordingly, this specimen would be the obligate choice of lectotype of L. undulata. In contrast, the long-standing interpretation of “Mart. herb. fl. bras. no. 1031” as the type of L. undulata likely results from an early herbarium misidentification, as these specimens bear identification labels as L. undulata in handwriting comparable to that found on M-0165314. The original material of Lantana undulata (M-0165314) does not correspond to the species concept currently applied under this name (e.g., Schauer, l.c. 1847, l.c. 1851; Silva, l.c. 1999; Salimena, l.c.; Silva & Lima, l.c.; Cardoso & al., l.c. 2021a; Silva & al., l.c. 2026). Instead, it is conspecific with Lippia aristata Schauer (l.c. 1847: 581), characterized by leaves with dentate margin, bracts with aristate or caudate apex, white corollas with yellow throat, and schizocarpic fruits. Strict application of priority would therefore require the transfer of Lantana undulata to Lippia, with Lippia aristata and its 11 heterotypic synonyms (Salimena & Cardoso in Flora & Funga do Brasil. 2026, accessed 6 Feb 2026) placed in synonymy. Furthermore, recognition of the taxon currently treated as Lantana undulata sensu Schauer (l.c. 1847) would require the creation of a new species name, potentially by elevating L. undulata var. grandiflora Schauer or L. radula subsp. glabrescens Hayek to species rank. The former was treated as a synonym of L. undulata by Silva (l.c. 1999), whereas the latter is here considered conspecific with L. undulata based on our taxonomic analyses. We argue that such a change would not represent the most appropriate solution, as it would substantially disrupt nomenclatural stability. Lantana undulata sensu Schauer (l.c. 1847, l.c. 1851) is a well-known species in Brazil. Beyond the taxonomic treatments (cited above), several studies have emphasized its medicinal value (e.g., Silva & al. in Asian J. Sci. Tech. 9: 8722–8726. 2018; Ascendino & al. in Nat. Prod. J. 12(4): 33–39. 2022) and ecological relevance (Brugnerotto & al. in Res. Soc. Developm. 10(7): 8. 2021; Santana & al. in Flora 296: 152152. 2022). It is also frequently cited in floristic inventories (e.g., Camargo & al. in Revista Ceciliana 1(2): 78. 2009; Rollo & al. in UNISANTA BioSci. 2: 57. 2013; Alves & al. in Hoehnea 42: 590. 2015; Souza & al. in Hoehnea 42: 88. 2015; Pereira & Menezes, Restingas Espírito Santo: Veg., Fl., Distr. Geogr. Esp.: 97, 290. 2023; Souza & al., Guia Pl. Dunas Restingas: 520. 2025). On the speciesLink platform alone (https://specieslink.net/search/, accessed 6 Feb 2026), more than 900 specimens are identified as L. undulata across many herbaria. Lippia aristata is a well-known species of Verbenaceae, recorded in Argentina, Bolivia, Brazil, and Paraguay. It has notable medicinal relevance and is widely cited in studies addressing chemical composition (e.g., Terblanché & Kornelius in J. Essential Oil Res. 8: 474. 1996; Silva & al. in Revista Bras. Farmacogn. 20: 843–849. 2010; Singulani & al. in J. Med. Pl. Res. 6: 4416–4422. 2012; Okhale & al. in Int. J. Pharmacogn. 3: 202. 2016; Campos & al. in Revista Bras. Farmacogn. 33: 989–1000. 2023). It also has been frequently treated in taxonomic and nomenclatural works (e.g., Silva in Taxon 50: 1117. 2001; Silva & Salimena in Darwiniana 40: 58. 2002; Salimena & Múlgura in Rodriguésia 66: 193. 2015; Cardoso & al. in Brittonia 73: 447. 2021b; Mirra & al. in Ann. Missouri Bot. Gard. 109: 440. 2024), in phylogenetic studies (e.g., Lu-Irving & al. in Amer. J. Bot. 108: 1354–1373. 2021; O'Leary & al. in Taxon 72: 572–589. 2023), and cytogenetic and palynological investigations (e.g., Campos & al. in Pl. Syst. Evol. 291: 133–140. 2011; Sousa & al. in Anais Acad. Bras. Ci. 85: 147–157. 2013). On the speciesLink platform (https://specieslink.net/search/, accessed 6 Feb 2026), more than 430 specimens are identified as L. aristata. As outlined above, the strict application of the name Lantana undulata based on Schrank's original specimen would require nomenclatural and taxonomic changes that would threaten the stability of two widely used names. Therefore, we propose the conservation of the name L. undulata with a conserved type (Art. 14.9) that corresponds to the current species concept, thereby maintaining nomenclatural stability. This will preserve the current usage of both L. undulata and Lippia aristata and prevent undesirable nomenclatural changes affecting taxonomic, biochemical, ecological, and related research, while also avoiding substantial consequences for herbarium identifications, as updating specimen determinations is typically a slow process that relies largely on in situ technical visits by specialists. The proposed conserved type (M barcode M-0111631) was likely collected by Bernhard Luschnath from Bahia (Ilhéus), Brazil between 1835 and 1837 (see Martius & al., Fl. Bras. 1: 49. 1906) and has duplicates, only one of which (BR0000005504305) bears Martius's original label, in several herbaria. These were distributed as “Martii Herbar. Florae Brasil. No. 1031”, an exsiccatum which, as mentioned above, has historically though incorrectly been considered the type of the name L. undulata. The duplicates found are as follows: BM barcode BM000992649, BR barcodes BR0000005504619, BR0000005504633, BR0000005504947, BR0000005504985 & BR0000005504305 [left-hand specimen], G barcodes G00366440 & G00366434, K barcode K000470739, M barcode M-0111629, NY barcode 00214337, P barcode P00713631, and S No. S04-2479.