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Weeding the Nettles II: A delimitation of “Urtica dioica L.” (Urticaceae) based on morphological and molecular data, including a rehabilitation of Urtica gracilis Ait.

Tilo Henning, Dietmar Quandt, Bernadette Grosse-Veldmann, Alexander Monro, Maximilian Weigend


The taxonomy of subcosmopolitan Urtica dioica L. s.l. is problematic. Recent floras recognize Urtica dioica as a subcosmopolitan species ranging throughout the entire holarctic region and also South Africa and New Zealand. Numerous infraspecific taxa have been proposed, especially in western Eurasia. There is only weak character differentiation, with floral and fruit morphology largely uniform, details of leaf morphology and indumentum are therefore primarily used for species delimitation, together with some characters of gender distribution and growth habit. The present study addresses the enigmatic relationships of the infraspecific taxa in Urtica dioica with a special emphasis on the monoecious, American representatives of Urtica dioica s.l. The study is based on extensive field and herbarium studies, molecular data and the experimental cultivation of all relevant forms. Infraspecific taxa currently assigned to U. dioica are retrieved mainly on two separate clades, one comprising the predominantly polygamous western Eurasian and African taxa (all subspecies and varieties sampled), the other comprising the monoecious American taxa. Monoecious American representatives of “Urtica dioica” and closely allied taxa (U. aquatica, U. mollis) are retrieved as a monophyletic group sister to a clade with East Asian and Australasian species, this clade is then retrieved as sister to the western and central Eurasian and African taxa of U. dioica. We therefore advocate the removal of the American representatives of this group from Urtica dioica and their placement as infraspecific taxa under Urtica gracilis. The following new names are consequently proposed: Urtica gracilis subsp. gracilis (for Urtica dioica subsp. gracilis), Urtica gracilis subsp. holosericea, comb. nov. (for Urtica dioica subsp. holosericea), Urtica gracilis subsp. aquatica, comb. & stat. nov. (for Urtica aquatica), Urtica gracilis subsp. mollis, comb. & stat. nov. (for Urtica mollis). Additionally, we describe a new subspecies from Peru under the name Urtica gracilis subsp. incaica. The literature report of Urtica gracilis (dioica subsp. gracilis) as an introduced weed in New Zealand is shown to be erroneous – the corresponding specimens belong to Australian Urtica incisa. Based on gross morphology close affinities have been proposed between a range of Australasian, Asian, North American and European infraspecific taxa, all of these can be shown to be erroneous.


Urtica angustifolia, monoecy, stinging nettle, phylogeny, chloroplast markers

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Ahti, T. & Hämet-Ahti, L. (1971) Hemerophilous flora of the Kuusamo district, northeastern Finland, and the adjacent parts of Karelia, and its origin. Annales Botanici Fennici 8(1): 1–91.

Aiton, W., Bauer, F.A., Ehret, G.D., Nicol, G. & Sowerby, J. (1789) Hortus Kewensis, or, A catalogue of the plants cultivated in the Royal Botanic Garden at Kew 3. Printed for George Nicol, Bookseller to his Majesty, London, 341 pp.

Blume, C.L. (1856) Museum botanicum Lugduno-Batavum, sive, Stirpium exoticarum novarum vel minus cognitarum ex vivis aut siccis brevis expositio et descriptio 2. Rijksherbarium, Leiden Netherlands, 256 pp.

Borsch, T., Hilu, K.W., Quandt, D., Wilde, V. Neinhus, C. & Barthlott, W. (2003) Noncoding plastid trnT-trnF sequences reveal a well resolved phylogeny of basal angiosperms. Journal of Evolutionary Biology 16: 558–576.

Borsch, T., & Quandt, D. (2009) Mutational dynamics and phylogenetic utility of noncoding chloroplast DNA. Plant Systematics and Evolution 282: 169–199.

Boufford, D.E. (1997) Urticaceae. In:. Flora of North America Editorial Committee (eds.) Flora of North America (North of Mexico) 3. New York. pp. 400–405.

Cheeseman, T.F. (1925) Urticaceae. In: Oliver, W.R.B. (eds.) Manual of the New Zealand Flora 2. W.A.G. Skinner, Wellington, pp. 380–382.

Conzatti, C. (1988) Flora taxonómica mexicana I. Consejo Nacional de Ciencia y Tecnología: Mexico City.

Domin, K., (1944) Monogrfická studie o kopřivĕ dvoudomé (Urtica dioica L.) Čas. Českého Lékárnictva 57: 59–75.

Edmondson, J.R. (1992) Urticaceae. In: Tutin, T.G., Burges, N.A., Chater, A.O., Edmondson, J.R., Heywood, V.H., Moore, D.M. Valentine, D.H., Walters, S.M. & Webb, D.A. (eds.) Flora Europaea 1, ed. 2. Cambridge University Press, Cambridge, pp. 79–81.

Friis, I. (1993) Urticaceae. In: Kubitzki, K. (ed.) The Families and Genera of Vascular Plants II. Springer Verlag, Berlin, pp. 612–629.

Friis, I. & Immelman, K. L. (2001) Part: Urticaceae. In: Germishuizen, G. (ed.) Flora of Southern Africa 9. National Botanical Institute, Pretoria, pp. 1–36.

Farag, M.A., Weigend, M., Luebert, F., Brokamp, G. & Wessjohann, L.A. (2013) Phytochemical, phylogenetic, and anti-inflammatory evaluation of 43 Urtica accessions (stinging nettle) based on UPLC-Q-TOF-MS metabolomics profiles. Phytochemistry 96: 170—183.

Geltman, D.V. (1982) The genus Urtica (Urticaceae) in the Flora of East Siberia and the Far East of the USSR. Botanicheskii Zhurnal 67: 194–207.

Ghafoor, A. (1977) Urticaceae. In: Jafri S.M.H. & El-Gadi, A. (eds.) Flora of Libya 47: Al Faateh University, Tripoli, pp. 1–15.

Gottschling, M. & Hilger, H.H. (2001) Phylogenetic analyses and character evolution of Erethia and Bourreria (Erethiaceae, Boraginales) and their allies based on ITS1 sequences. Botanische Jahrbücher für Systematik 123: 249–268.

Greene, E.L. (1889) New and noteworthy species IV. Pittonia 1: 280–287.

Hadiah J.T., Conn B.J. & Quinn C.J. (2008) Infra-familial phylogeny of Urticaceae, using chloroplast sequence data. Australian Systematic Botany 21: 375–385.

Hamilton, M.B. (1999) Four primer pairs for the amplification of chloroplast intergenic regions with intraspecific variation. Molecular Ecolology 8: 521–523.

Handel-Mazzetti, H.R.E. & Brotherus V.F. (1929) Symbolae sinicae: Botanische ergebnisse der expedition der Akademie der Wissenschaften in Wien nach Südwest-China 1914/1918. Vol. 7. J. Springer.

Heemskerk, M., Oliehoek, J. & Jong, T. de (1998) Eenhuizigheid en sex-ratio bij Grote brandnetel (Urtica dioica L.). Gorteria 24: 88–89.

Hitchcock, C.L., Cronquist, A., Ownbey, M. & Thompson, J.W. (1964) Vascular plants of the Pacific Northwest. Part 2. Salicaceae to Saxifragaceae. University of Washington Press, Seattle, Washington, 597 pp.

Holmgren, P.K. & Holmgren, N.H. (1998- continuously updated) Index Herbariorum. Available from:

Jepson, W.L. (1901) A Flora of western middel California. Encina publishing company, Berkeley California.

Jepson, W.L. (1909) A flora of California. Cunnigham, Curtiss & Welch, San Francsico, California.

Jiarui, C., Chia-jui, C., Qi, L., Friis, I., Wilmot-Daer, C.M. & Monro, A.K. (2003) Urticaceae. In: Zhengyi, W. & Raven, P. (eds.) Flora of China 5. Missouri Botanical Garden Press and Science Press, St. Louis and Beijing, pp. 76–189.

Juárez, F.C. (1991) Flora del Valle de Lerma, Urticaceae Jussieu. Aportes Botánicos de Salta – Serie Flora. 1/6: 1–15.

Kelchner, S.A. (2000) The evolution of non-coding chloroplast DNA and its application in plant systematics. Annals of the Missouri Botanical Garden 87: 482–498.

King, C. (1871) Report of the Geological Exploration of the Forthieth Parallel Vol. 5. Washington D.C., 321 pp.

Lamarck, J.B.A.P.M. de (1816) Encyclopedie Methodique. Botanique. Supplement 4. Agasse, Paris, 731 pp.

Ledebour, C.F. (1833) Flora Altaica. G. Reimer, Berlin, 201 pp.

Liebmann, F.M. (1851) Mexicos og Central-Americas neldeagtige Planter (Ordo: Urticaceae). Kongelige Dankse Videnskabernes Selskabs Skrifter. Femte Reakke. Naturvidenskabelig og Mathematisk afdeling 5(2): 286–343.

Linnaeus, C. (1753) Species Plantarum, Vol. 2. Laurentius Salvius, Stockholm. pp. 561–1200.

Loiseleur-Deslongchamps, J.L.A. (1827) Nouvelle notice sur les plantes à ajouter à la Flore de France (Flora Gallica). Mémoires de la Société Linnéenne de Paris, 6. Au secrétariat de la Socièté linnèenne, Paris, pp. 396–432.

Navas, E. (1961) El género Urtica en Chile. Boletín de la Sociedad Argentina de Botánica 9: 395–413.

Müller, K. (2004) PRAP—computation of Bremer support for large data sets. Molecular Phylogenetics and Evolution 31: 780–782.

Müller, J., Müller, K., Quandt, D. & Neinhuis, C. (2005) PhyDE–Phylogenetic Data Editor, version 0.995 (online). Available from: (accessed 1 January 2010).

Nixon, K.C. (1999) The parsimony ratchet: a rapid means for analyzing large data sets. Cladistics 15: 407–414.

Nurmi, J. & Faurholdt, N. (2000) 31. Urticaceae. In: Jonsell, B. (ed.) Flora Nordica 1. Bergius Foundation, Stockholm, pp. 222–229.

Nuttal, T., Cassin, J. & Leidy, J. (1848) Descriptions of plants collected by Mr. William Gambel in the Rocky Mountains and upper California. Proceedings of the Academy of Natural Sciences of Philadelphia 4: 7–28.

Philippi, R.A. (1864) Plantarum novarum chilensium. Centuria inclusis quibusdam Mendocinis et Patagonicis. Linnaea 33: 1–308.

Pollard, A.J. & Briggs, D. (1982) Genecological studies of Urtica dioica L. I. The Nature of infraspecific Variation in U. dioica. New Phytologist 92: 453–470.

Pollard, A.J. & Briggs, D. (1984) Genecological studies of Urtica dioica L. II. Patterns of variation at Wicken Fen, Cambridgeshire, England. New Phytologist 96: 483–499.

Quandt, D., Müller, K. & Huttunen, S. (2003) Characterisation of the chloroplast DNA psbT-H region and the influence of dyad symmetrical elements on phylogenetic reconstructions. Plant Biology 5: 400–410.

Rambaut, A. & Drummond, A.J. (2009) Tracer v1.5 (online). Available from: (accessed 1 January 2013).

Rogowisz, A.S. (1843) Urtica kioviensis. Species Nova Plantarum. Bulletin de la Société Imperiale des Naturalistes de Moscou 2.

Ronquist, F. & Huelsenbeck, J.P. (2003) Bayesian phylogenetic inference under mixed models. Bioinformatics 19: 1572–1574.

Ross, H. (1905) Beiträge zur Kenntnis der Pflanzenwelt Südamerikas. Österreichische Botanische Zeitschrift 55: 466–468.

Rydberg, P.A. (1897) Rarities from Montana. Bulletin of the Torrey Botanical Club 24 (4): 188–192.

Rydberg, P.A. (1912) Studies of the rocky mountain flora. Bulletin of the Torrey Botanical Club 39 (7): 301–328.

Sang T., Crawford, D.J. & Stuessy, T.F. (1997) Chloroplast DNA phylogeny, reticulate evolution, and biogeography of Paeonia (Paeoniaceae). American Journal of Botany 84: 1120-1136.

Selander, S. (1947) Urtica gracilis Ait. in Fennoscandia. Svensk Botanisk Tidskrift 41 (2): 264–282.

Shannon, R.K., Holsinger, K.E. (2007) The genetics of sex determination in stinging nettle (Urtica dioica). Sexual Plant Reproduction 20 (1): 35–43.

Soraru, S.B. (1972) Revisión de las “Urticaceae” argentinas. Darwiniana 17: 246–279.

Stamatakis, A. (2006) RAxML-VI-HPC: Maximum Likelihood-based Phylogenetic Analyses with Thousands of Taxa and Mixed Models”. Bioinformatics 22: 2688–2690.

Steudel, E.G. (1850). Urticeae nondum descriptae. Flora (Regensburg) 17: 257–261.

Stöver, B. & Müller, K.F. (2010) TreeGraph2: Combining and visualizing evidence from different phylogenetic analyses. BMC Bioinformatics 11: 7.

Swofford, D.L. (2002) PAUP*. Phylogenetic Analysis Using Parsimony (*and Other Methods), version 4. Sinauer Associates, Sunderland, Massachusetts.

Taylor, C. (2003) Urticaceae. In: Marticorena C. & Rodríguez, R.A. (eds.) Flora de Chile 2(2). Ediciones de la Universidad de Concepción, Concepción, pp. 44–61.

Taylor, R.L. & MacBryde, B. (1977) "Vascular plants of British Columbia: A descriptive resource inventory." Vancouver: University of British Columbia Press xxiv (Technical Bulletin, no. 4)-Map. Maps. Geog 3, 754 pp.

Thorne, R.F. (1967) A flora of Santa Catalina Island, California. Aliso 6(3): 1–77.

Watson, S. (1875) Revision of the Genus Ceanothus, and Descriptions of New Plants with a Synopsis of the Western Species of Silene. Proceedings of the American Academy of Arts and Sciences (10) 333–350.

Webb, C.J., Sykes, W.R. & Garnock-Jones, P.J. (1988) Flora of New Zealand, Vol. IV: Naturalised Pteridophytes, Gymnosperms, Dicotyledons. Botany Division, Christchurch, 1365 pp.

Weddell, H.A. (1856) Monographie de la famille des Urticées. Archives du Museum National d'Histoire Naturelle Paris 9, G. & J. Baudry, Paris, pp. 1–592.

Weddell, H.A. (1869) Urtica. In: Candolle, A.P. de (ed.) Prodromus Systematis Naturalis Regni Vegetabilis 16, Paris, pp. 39–67.

Weddell, H.A. (1869) Urticaceae. In: Candolle, A.P. de (ed.) Prodromus Systematis Naturalis Regni Vegetabilis 16, Paris, pp. 32–235.

Weigend, M. (2005) Die Erben Pokornys – Ein Beitrag zur Abgrenzung der enigmatischen Sippen Urtica galeopsifolia und Urtica pubescens in Mittel- und Osteuropa. Hoppea 66: 101–117.

Weigend, M. (2006) Urtica dioica subsp. cypria, with a re-evaluation of the U. dioica group (Urticaceae) in western Asia. Willdenowia 36: 811–822.

Weigend, M. & Luebert, F. (2009) Weeding the nettles I: Clarifying species limits in perennial, rhizomatous Urtica (Urticaceae) from southern and central Chile and Argentina. Phytotaxa 2: 1–12.

Weigend, M., Gottschling, M., Selvi, F. & Hilger, H.H. (2010) Fossil and Extant Western Hemisphere Boragineae, and the Polyphyly of "Trigonotideae" Riedl (Boraginaceae: Boraginoideae). Systematic Botany 35: 409–419.

White, T.J., Bruns, T., Lee, S. & Taylor, J. (1990) Amplification and direct sequencing of fungal ribosomal ribosomal RNA genes for phylogenetics. In: M. Innis, D. Gelfand, J. Sninsky & T. White (eds.) PCR protocols: a guide to methods and applications., Academic Press, San Diego, pp. 315-322.

Willdenow, K.L. (1805) Species plantarum Vol. 4., G.C. Nauk, Berlin.

Wimmer, F. & Grabowski, H. (1829) Flora Silesiae 2. Vratislaviae.

Woodland, D.W. (1982) Biosystematics of the perennial North American taxa of Urtica. II. Taxonomy. Systematic Botany 7: 282–290.

Woodland, D.W., Bassett, I.J., Crompton, C. & Forgét, S. (1982) Biosystematics of the Perennial North American Taxa of Urtica I. chromosome Number, Hybridization and Palynology. Systematic Botany 7: 269-281.

Wu, Z-Y., Monro, A.K., Milne, R.I., Wang, H., Yi, T-S., Liu, J. & Li, D-Z. (2013) Molecular phylogeny of the nettle family (Urticaceae) inferred from multiple loci of three genomes and extensive generic sampling. Molecular Phylogenetics and Evolution 69: 814–827.


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