Revised Species Delimitation in the Giant Water Lily Genus Victoria (Nymphaeaceae) Confirms a New Species and Has Implications for Its Conservation Author Smith, Lucy T. Royal Botanic Gardens, Kew, Richmond, United Kingdom. Author Magdalena, Carlos Royal Botanic Gardens, Kew, Richmond, United Kingdom. c.magdalena@kew.org Author Przelomska, Natalia A. S. Royal Botanic Gardens, Kew, Richmond, United Kingdom & National Museum of Natural History, Smithsonian Institution, Washington, DC, United States. Author Pérez-Escobar, Oscar A. Royal Botanic Gardens, Kew, Richmond, United Kingdom. o.perez-escobar@kew.org Author Melgar-Gómez, Darío G. Herbario German Coimbra Sanz, Jardín BotAEnico Municipal de Santa Cruz de la Sierra, Santa Cruz de la Sierra, Bolivia. Author Beck, Stephan Herbario Nacional de Bolivia, Universidad Mayor de San AndrØs, La Paz, Bolivia. Author Negrão, Raquel Royal Botanic Gardens, Kew, Richmond, United Kingdom. Author Mian, Sahr Royal Botanic Gardens, Kew, Richmond, United Kingdom. Author Leitch, Ilia J. Royal Botanic Gardens, Kew, Richmond, United Kingdom. Author Dodsworth, Steven School of Biological Sciences, University of Portsmouth, Portsmouth, United Kingdom. Author Maurin, Olivier Royal Botanic Gardens, Kew, Richmond, United Kingdom. Author Ribero-Guardia, Gaston La Rinconada Ecoparque, Santa Cruz, Urbari, Bolivia. Author Salazar, César D. Calle 11 Norte # 24, Urbari, Bolivia. Author Gutierrez-Sibauty, Gloria Herbario German Coimbra Sanz, Jardín BotAEnico Municipal de Santa Cruz de la Sierra, Santa Cruz de la Sierra, Bolivia. Author Antonelli, Alexandre Royal Botanic Gardens, Kew, Richmond, United Kingdom & Gothenburg Global Biodiversity Centre, Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden & Department of Plant Sciences, University of Oxford, Oxford, United Kingdom. Author Monro, Alexandre K. Royal Botanic Gardens, Kew, Richmond, United Kingdom. a.monro@kew.org text Frontiers in Plant Science 2022 2022-07-04 13 1 31 http://dx.doi.org/10.3389/fpls.2022.883151 journal article 10.3389/fpls.2022.883151 fe85e7a5-8a98-43bc-9a44-7d6a10241556 PMC9289450 35860537 7576624 Victoria cruziana Orb., Ann. Sci. Nat., Bot. , sér. 2 , 13: 57 (January 1840). Type: Bolivia [ Argentina ], Corrientes , banks of the Paraná river , Arroyo de San José , beginning of 1827, d’Orbigny s.n. ( lectotype : P ( P02048598 ∗ ) (designated by de Lima etal., 2021 ); isolectotypes : P ( P02048599 ). Vernacular names: Irupé (yrupé), yacare yrupé, naanók lapotó (poncho del otany), maíz de agua, Santa Cruz Waterlily, Victoria regia . Figures 1C , 3G–I , 6 , 11 . Victoria regia var. cruziana (Orb.) G. Lawson , Proc. & Trans. Roy. Soc. Canada 6(4): 109 (1889) Euryale brasiliana Steud. , Nomencl. Bot. [Steudel], ed. 2. 1: 617 (November 1840). Euryale policantha Rojas Acosta , Cat. Hist. Nat. Corrientes 65 (1897) . Euryale bonplandia Rojas Acosta , Cat. Hist. Nat. Corrientes 151 (1897). Victoria cruziana f. trickeri Henkel ex Malme , Acta Horti Berg. 4(5): 12. 1907 (“Trickeri”), nom. nud. Leaves up 2.4 m broad, adaxial surface of lamina green, abaxial surface of lamina green or dark blue-green, radial and reticulate ribs yellow or green; leaf margins form a high rim 8–10% of leaf length, rim ± perpendicular to or slightly recurved over adaxial surface at base, flared outwards at top (sigmoid in profile), abaxial surface of rim green or tinged maroon, hairs 1–3 mm, simple, multicellular, 10–15 segmented. Flower bud broadly ovoid, concave just before apex, up to 30 cm diameter at secondnight anthesis. Ovary 7–10 cm diameter, outer surface covered in prickles 1–22 mm (dried), prickles abruptly tapering from c. half their length to sharp apex; hairs absent or present, where present 0.1–12 mm; inner surface of ovary with moderately concave stigmatic surface, rounded to triangular in longitudinal profile, ridged with lines corresponding with 25–38 radially arranged locules, each containing 20–25 ovules 1.5–1.8 mm (fresh). Outer tepals 4, 10–13 × 4–9 cm when fresh, abaxial surface green and/or tinged maroon abaxially prickles absent or present, where present up to 100 per tepal, prickles tapering abruptly at their midpoint to a sharp point, 1–10 mm (dried), distributed up to lower one third of surface, hairs absent or present, where present 0.1–1 mm. Inner tepals 7–10 × 1.5–9 cm (fresh), innermost all white both in bud and during first-night anthesis, crinkled in appearance, turning pale to dark pink on second-night; outer staminodia, 6– 7 × 1–1.5 cm, thick, rigid, apiculate; stamens 4–6 × 0.5–1 cm inner staminodia> 50, 4–6 × 0.5 cm; base of lower parts of carpellary appendage flat, arising from stigmatic surface at 45 degree angle, cuneate, length of upper parts not exceeding that of lower parts. Flower at first night of anthesis: all inner tepals white, outer staminodia tipped pink; at second night anthesis, outer tepal adaxial surface pink, inner tepals pale or dark pink at base, white or pink towards apex, outer staminodia dark pink for basal two-thirds of their length, white then pink towards apex, inner staminodia pink at base. Seeds, c. up to 1000 per fruit, 7–9 × 8–10 mm, globose, raphe faintly visible, brown to black, surrounded by a mucilaginous aril. Distribution and Conservation Status Victoria cruziana f. mattogrossensis taxon incertum has hitherto been included within Victoria cruziana until this study. Because our genomic analyses are limited with respect to the rank of this taxon and of its relationship to the other species, we have not considered forma mattogrossensis taxon incertum as conspecific with V. cruziana for the purposes of an extinction risk assessment. Victoria cruziana is restricted to the Paraná river basin and tributaries, from Paraguay to Argentina, and possibly Bolivia. Based on the maximum potential habitat of wetlands (including Esteros de Ibera National Park Wetlands) and a combination of verified herbarium collections and iNaturalist images we estimate the EOO of V. cruziana to be between 46,563 and 132,945 km 2 . Thisexceeds the threshold fora threatened category under criterion B (IUCN Standards and Petitions Committee, 2019). We calculate the AOO to be 120 km 2 , although an upper estimate based on the extent of the river may exceed 2,000 km 2 (but not more than 3,000 km 2 ). This would assess V. cruziana as between Endangered and Vulnerable categories. There are more than 10 locations but no information about population fragmentation. We infer a continuing decline in habitat quality due to the increasing frequency of droughts, the abstraction of water, deforestation (Caivano and Calatrava, 2021; Comisión Nacional de Actividades Espaciales, 2021 ) and big hydroelectric dams. For example, Itaipu is one of the largest dams in the world ( Stevaux et al., 2009 ) and lies within the V. cruziana range. Whilst the AOO upper estimate is close to the threshold for VU, there are more than sufficient criteria for a threatened category under criterion B, and we therefore assess V. cruziana as LC. We recommend further documentation of the distribution and size of V cruziana populations and investigations into their fluctuation through time as we believe that it may be vulnerable to an increase in the frequency and severity of droughts associated with climate change and increased sedimentation caused by the construction of large dams within its habitat ( Stevaux et al., 2009 ). Notes. Victoria cruziana forms the proportionately highest leaf rims of all the species, and these are always slightly recurved over the flat part of the lamina, flaring out at the top. The concavity of the outer tepals before their apex gives the bud a pinched-in appearance. Prickles are absent or occur on the outer tepal abaxial surface, but only up to one-third of their length from the base. In this species, hairs which are sometimes present on the lower outer tepal abaxial surface and ovary are the only ones large enough to see without magnification. At first night anthesis, inner tepals have a crinkled appearance. Victoria cruziana f. mattogrossensis taxon incertum was described by Malme based on material present in the spirit collection of the Swedish Museum of Natural History comprising two jars of the same gathering. S07-84 comprises a longitudinal section through the ovary and perianth showing clearly the distribution of prickles and their form on both the ovary and outer tepals, also the morphology of the carpellary appendages; S07-85 comprises sections of the petiole apex and either the petiole or pedicel. Both are preserved in excellent condition. S07-84 was selected as lectotype as it displayed a greater number of diagnostic morphological features. Victoria cruziana f. mattogrossensis taxon incertum was described from, and material corresponding to it has only been observed from the Pantanal, in Bolivia, Brazil and Paraguay in the Uruguay river basin. Phylogenomic data were unable to confirm whether the material sampled represents a distinct evolutionary lineage (see section “Discussion”). It may be that further sampling and research supports the recognition of this name as a distinct taxon. Material Examined. ARGENTINA . Chaco : 1st De Mayo , Laguna en Chacra , al lado del arroyo Ine , –58.849444 , – 27.416389 , 02/03/2006 , Mulgura de Romero, M. E. , Anisko, T. , Harbage, J. , Illarrage, H. 4249 ( SI ); San Fernando , Entre Barranqueras e Isla Antequera, –58.87944 , –27.416389 , 18/03/1967 , Krapovickas, A. and Cristobal, C. L. 12752 ( MO ). Corrientes : Capital , Riachuelo , off Ruta 12 ca 17 km Sof Corrientes , –58.749444 , –27.554444 , 06/04/1982 , Schinini, A . Wiersema, J. H. 2243 ( MO ); Esquina, Isla Correntina frente a curuzu – Chali , en el Paraná medio, –59.630833 , –30.341944 , 10/04/1968 , Burkart, A. , Troncoso, N. S. , Guaglianone, E. R. and Palacios, R. A. 26963 ( SI ); San Roque, R. Santa Lucia , – 58.738056 , –28.576944 , 27/02/1957 , Pedersen, T. M. 4486 ( K , MO ); Bella Vista, Cruce Ruta Nacional 12 Ey Puente Sobre Lel Río Santa Lucia , –58.72 , –28.57 , 12/04/2008 , Mulgura de Romero, M. E. , Aniśko, T. , Belgrana, M. J. and Harbage, J. 4474 ( SI ); Dep. Esquina , Río Guayguiraro , –59.56 , –30.374444 , 26/02/1974 , Quarin, C. , Schinini, A . Gonzales, J. M. , Ishikawa, A. 2196 ( K ). Santa Fe: La Capital, Ruta Nacional 168 y Puente no. 9, Sobre Arroyo mini , al E-SE de la Ruta Prov. 1. W, – 60.575833 , –31.672778 , 12/04/2008 , Mulgura de Romero, M. E. , Anisko, T. , Belgrana, M. J. and Harbage, J. 4477 ( SI ). BOLIVIA . Santa Cruz : Angel Sandoval , channel at southern end of Laguna Mandiore , –57.483333 , –18.216667 , 16/07/1998 , Ritter, N. , Crow, G. E. , Garvizu, M. and Crow, C. 4562 ( LPB , MO ) [ f. mattogrossensis ], Ritter, N. , Crow, G. E. , Garvizu, M. and Crow. C. 4560 ( LPB , MO ). BRAZIL . Mato Grosso du Sul : Corumba , Cacimba da Saude , – 57.664167 , –18.99833 , 13/12/2002 , Avellar, A. L. F. 13 ( COR ) [ f. Mattogrossensis ]; Ladario , terminal da Branave , no porto de Ladario , –57.584722 , –19.0225 , 12/08/1994 , Sanches, A. L. , Bortolotto, J. M. , Damascenos Jr., G. 44 ( COR ) [ f. mattogrossensis ]; Corumba , Ladario , CODRASA Brejo (swamp), – 57.516389 , –19.021111 , 27/11/2004 , Souza Jr., A. F. , and Siqueira, C. S. 39 ( COR ) [ f. Mattogrossensis ]; Corumba , Ladario , –57.580556 , –19.001111 , –/07/1894, Anon s.n. [G. O. A. Malme] S07-785 , S07-784 ( S ). PARAGUAY . Distrito Capital : L’Assumption [in the swamps], –57.604167 , –25.256667 , 17/03/1875 , Balansa, R. 523 ( K , P ). Central : Piquete Cue , –57.666667 , –25.166667 , 29/11/2000 , Zardini, E. M. and Guerrero, L. 55181 ( MO ); Bay of Ascuncion , wetlands, –57.61922 , –25.273333 , 15/03/1988 , Ericsson, K. 577 ( MO ). Neembucu : Yataity , –58.040556 , –26.788611 , –/03/1975, Walter, M. A. 86 ( K ); Pilar Garden Club S, –58.276389 , –26.867778 , 28/01/2005 , De Egea Juvinel, J. , Pena-Chocarro, M.. , Vera, M. , Torres, M.. and Elsam, R. 738 ( MO ). Presidente Hayes : Riacho Pucu ., – 57.083333 , –24.666667 , 20/08/2000 , Zardini, E. M and Guerrero, L. 54765 ( MO ); 12/02/1987 , Sparre 2363/51 ( P ).