Taxonomy, morphology and cytology of Micranthes virginiensis (Michaux) Small (Saxifragales, Saxifragaceae), new chromosome counts for Micranthes and description of a new Micranthes species from the south-eastern USA

309 Taxonomy, morphology and cytology of Micranthes virginiensis (Michaux) Small (Saxifragales, Saxifragaceae), new chromosome counts for Micranthes and description of a new Micranthes species from the south-eastern USA Tara K. Hall1, Luiz F. L. da Silveira1, Max S. Lanning2, Katherine G. Mathews1 1 Department of Biology, Western Carolina University, Cullowhee, North Carolina, 28723, USA 2 Department of Geosciences and Natural Resources, Western Carolina University, Cullowhee, North Carolina, 28723, USA Corresponding author: Katherine G. Mathews ([email protected]) Copyright: © Tara K. Hall et al. This is an open access article distributed under terms of the Creative Commons Attribution License (Attribution 4.0 International – CC BY 4.0). Research Article Abstract Micranthes virginiensis (Saxifragaceae) is an herbaceous, flowering plant species native to eastern North America with a range extending from the Gulf of Mexico into Canada. This broad range, known from previous studies to contain individuals with varying chromosome numbers and morphological variation outside of the current formal description, indicates the need for a re-examination of the taxonomy of this species. Some populations in south-eastern Appalachia display intermediate traits between M. virginiensis and the peripatric congener M. careyana and have unresolved phylogenetic placement, raising the possibility of hybridisation. This study explored hypotheses of hybridisation and undescribed taxa within M. virginiensis, based on morphometric and chromosome data collected from samples across Eastern North America. Floral, fruit and leaf measurements were analysed to investigate morphological variation across the species’ range. Chromosome counts from south-eastern U.S.A. congener populations of M. careyana, M. palmeri and M. petiolaris all showed diploidy (2n = 20), representing the first known chromosome counts for these species. Tetraploidy and unique floral morphology in two populations of the Blue Ridge Escarpment of SC, where the distribution of M. virginiensis and M. careyana abut, indicate an undescribed species, possibly of hybrid origin. Other tetraploid populations in the south-eastern USA showed no morphological differences from diploid M. virginiensis, suggesting autopolyploidy. In addition, we document a trend of decreased reproductive investment with increasing elevation within M. virginiensis. Overall, the taxonomic boundaries across the broad range of M. virginiensis proved intact, aside from the escarpment tetraploid species. Here, we describe the new escarpment species, Micranthes scopularum Hall, Lanning & Mathews and provide a complete list of synonyms of M. virginiensis, in which we designate two lectotypes and one neotype. Key words: Blue Ridge Escarpment, chromosome numbers, hybrid species, Micranthes virginiensis, morphology, polyploid, Saxifragaceae, taxonomy Academic editor: Alina Freire-Fierro Received: 15 June 2025 Accepted: 5 November 2025 Published: 12 December 2025 Citation: Hall TK, da Silveira LFL, Lanning MS, Mathews KG (2025) Taxonomy, morphology and cytology of Micranthes virginiensis (Michaux) Small (Saxifragales, Saxifragaceae), new chromosome counts for Micranthes and description of a new Micranthes species from the south-eastern USA. PhytoKeys 267: 309–343. https://doi.org/10.3897/ phytokeys.267.162132 PhytoKeys 267: 309–343 (2025) DOI: 10.3897/phytokeys.267.162132 310 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Introduction Geographically widespread species often encompass considerable genetic and morphological variation as a result of adaptations to ecological differences across the range, genetic isolation and drift, migration, selection and genetic sorting (Karron 1987; Soltis and Soltis 1991; Wang et al. 2020). For example, a consequence of environmental heterogeneity can be significant variation in size and reproductive output of individual plants (Cheplick 2005). However, in some cases, variation is representative of undescribed species (Judd et al. 2007; Díaz-Tapia et al. 2018; Ji et al. 2020; Nesom 2021). One example of a geographically widespread, flowering plant species of Eastern North America with broad-scale morphological variation and multiple ploidy levels is Micranthes virginiensis (Michx.) Small (Saxifragaceae), often described as polymorphic (Engler 1872; Johnson 1923) and highly variable (Small 1896; Bush 1928; Lord 1960). Much of the morphological variation noted since the original description (as Saxifraga virginiensis Michaux, 1803) has been described at the species and subspecific levels, but most later names have subsequently been synonymised with Micranthes virginiensis (International Plant Names Index and external links, https://www.ipni.org/search?q=micranthes%20 virginiensis, accessed 11 June 2025). Some exceptional morphological variation has only recently been documented, namely unusual populations found in the Blue Ridge Escarpment region in South Carolina, U.S.A. In this study, we examined both morphological and cytological variation across the entire range of M. virginiensis, focusing on plants from the escarpment region, as well as geographical areas from which variants have previously been described, to determine if any constitute unique lineages and deserve species recognition. Past dramatic fluctuations in climate have resulted in many range changes within the genus Micranthes. This has led to disproportionate species richness in cold areas of high elevation and latitude, resulting in evolutionary complexities that remain difficult to disentangle, including hybridisation, cryptic species and variation in chromosome number (Stubbs et al. 2020a). For example, the Pacific North-western Micranthes hitchcockiana (Elvander) Brouillet and Gornall (n = 38) is believed to be of hybrid origin between M. rufidula Small (n = 19) and M. oregana (Howell) Small (n = 19) based on chromosome number and apparent morphological intermediacy (Elvander 1984). The most common chromosome numbers in this genus are 2n = 20, 38 and 56, with many species exhibiting several different counts, indicating that aneuploidy and polyploidy are rife throughout the clade (Stubbs et al. 2020a). The multiple instances of 2n = 20, 38 chromosomes in Micranthes may be a result of chromosome fusions followed by tetraploidisation (Stubbs et al. 2020a). As Micranthes virginiensis faces similar complexities to other members of this genus, a study to clarify morphological and cytological variation within the geographic range of this taxon and investigate potential cryptic lineages or hybrid populations would improve our understanding of the evolutionary history and taxonomy of this entity. Consideration of multiple lines of evidence when drawing species boundaries is crucial in a variable species like M. virginiensis, as the morphological, cytological and molecular variations noted in previous studies (Lord 1960; Soltis 1983; Lanning and Mathews 2019) indicate a potential for undescribed and/ or cryptic species. This is also true for other members of the Saxifragaceae, 311 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes as several studies in recent years have delimited new taxa in multiple genera through morphological, molecular and cytogenetic means. For example, Tiarella L., a genus long considered to represent only one eastern USA species, T. cordifolia L. (Weakley 2020), was recently split into five species, based on previously unnoticed morphological differences in stolon presence and leaf and bract shape (Nesom 2021). In a study examining the utility of nuclear ribosomal DNA sequences for delimiting species, Okuyama and Kato (2009) found evidence of at least three cryptic species in Mitella L. and suggested that many other angiosperm lineages contain cryptic species that could be discerned with molecular methods. Additionally, the genus Tolmiea Torr. & A. Gray held one species until recently, T. menziesii (Pursh) Torr. & A. Gray, containing both diploid and autotetraploid populations. Though the two cytological conditions were not easily morphologically distinguishable from one another, Judd et al. (2007) recognised the diploid entity as a unique species, T. diplomenziesii, due to the different geographic distributions and apparent reproductive isolation determined through artificial crossing studies. These studies underline the importance of integrative studies, especially in-depth morphological comparisons, when addressing plant species boundaries. Although numerous subordinate taxa have been described in M. virginiensis, none of them corresponds to populations with known differences in chromosome number. However, polyploidy may have taxonomic significance for this species. Soltis (1983) reported counts of 2n = 20 for plants from Massachusetts, Missouri, Tennessee, northern and western Virginia and Canadian populations and 2n = 38 in plants from North Carolina and eastern Virginia populations, the latter suspected of autopolyploidisation resulting in tetraploidy (2n = 40) followed by an aneuploid reduction (Soltis 1983). Additional counts in this species were done by Hill (2n = 20, 1989), Löve and Löve (2n = 28, 1982), Kovanda (n = 14, 2n = 28 as separate meiotic and mitotic counts, 1978) and Löve and Ritchie (1966). The populations of M. virginiensis that exhibit polyploidy could be reproductively isolated or associated with unique morphological or ecological characteristics, indicating potential undescribed or cryptic species, as in Tolmiea. A variable number of supernumerary chromosomes was also reported by Soltis (1983), which could be of taxonomic significance (D. Poindexter, pers. comm.), further evidencing the complexity of this species. Sister species of M. virginiensis (Stubbs et al. 2020b) that adjoin its distribution (Micranthes careyana (A. Gray) Small, M. caroliniana (A. Gray) Small, and M. palmeri (Bush) Bush have not had chromosome counts reported and the potential for hybridisation between M. virginiensis and its sister taxa is not known, therefore ploidy levels in this group are in need of further investigation and are a focus of this study. Micranthes virginiensis is found on rock outcrops, moist alluvial and slope forests, streambanks and riverbanks and has a broad distribution from southeast Canada throughout the eastern United States into Louisiana and Arkansas (Weakley (2025); Fig. 1). According to Brouillet and Elvander (2021), it grows at elevations of 0–1500 m, but in the Southern Appalachians, it is restricted to escarpment regions at around 340 m elevation. Lord (1960), who provided the most recent revision of species of Micranthes (as Saxifraga L.) in the Southern Appalachian Mountains, noted that M. virginiensis has long been known to exhibit vegetative variation, particularly concerning leaf shape and margins, distribution of pubescence and scape branching pattern; however, she determined 312 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Figure 1. Distributions of Micranthes virginiensis and three other south-eastern U.S.A. Micranthes species. Total distributions shown in map on the left. Inset map on the right centres on the Blue Ridge escarpment populations. Collections used for chromosome counts in this study with voucher specimens are outlined. Circles indicate diploid plants; triangles indicate tetraploid plants. Collected plants and voucher specimens were also used for morphological observations and measurements. that all individuals she studied were consistent in their presence of a hypanthium (sepals and petals partially fused to and forming a cup-like structure surrounding the ovary) and short stamen length relative to petal length when compared to peripatric Micranthes species. However, populations identified as M. virginiensis, but inconsistent with these floral characters, have recently been discovered on the Blue Ridge Escarpment of SC (Lanning and Mathews 2019), begging the question of potential undescribed species encompassed under the name. As taxa with cosmopolitan geographic distributions have been frequently shown to hold cryptic diversity (Díaz-Tapia et al. 2018; Wu et al. 2018; Whittall et al. 2020; Nesom 2021), the latitudinal and climatic variation in the distribution of M. virginiensis across the eastern United States makes it a likely candidate for harbouring undetected novel taxa. Hybridisation leading to allopolyploidy could result in hybrid speciation, in which the hybrid offspring can persist and maintain a stabilised hybrid lineage, generally recognised as a species, as this often results in reproductive isolation (Mallet 2007). In addition, many plant studies indicate that polyploid, hybrid species may form recurrently from different progenitor diploid populations and subsequently interbreed to form a polyphyletic species (e.g. Soltis and Soltis (1999); Sonnleitner et al. (2010); Symonds et al. (2010); Sampson and Byrne (2012)). A recent systematic study of M. caroliniana and M. careyana, two Southern Appalachian endemics, found these species to be phylogenetically closely related and morphologically similar to M. virginiensis (Lanning and Mathews 2019) and these relationships were later confirmed by Stubbs et al. (2020b), although they are not known to have the ability to hybridise. 313 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes During Lanning’s field collections, two putative M. virginiensis populations from Greenville and Pickens Co., SC, in the escarpment region were observed to have some floral characteristics more consistent with M. careyana, including long stamens and large fruits and lacking a conspicuous hypanthium, but without the petal spots characteristic of M. careyana (vegetatively, M. virginiensis and M. careyana are indistinguishable). These were included in Lanning and Mathews’ (2019) phylogenetic analyses, based on nrITS and cpDNA gene regions, which resulted in poor resolution amongst populations of these species and M. caroliniana, the cause of which was unknown. The Southern Blue Ridge Province, spanning the Appalachian Mountains from Virginia to Georgia, is known for high rates of endemism and species diversity, including a mixture of species of temperate, tropical and alpine origin and populations at the periphery of many northern and western species’ ranges (Pittillo et al. 1998). This is due to the unique microhabitats created by the geomorphic structure of this region range formed over hundreds of millions of years, as well as the glacial advance and retreat cycle of the past 2 Ma (Pittillo et al. 1998; McMillan et al. 2018). Endemic species, disjunct distributions and morphological oddities are commonplace in the escarpment region (e.g. Gray (1879); Wagner (1965); Billings and Anderson (1966); McMillan et al. (2018)). In fact, a new variety of Micranthes petiolaris (Raf.) Small was recently described from Wadakoe Mountain (var. shealyi P.D. McMillan & Cushman; Cushman et al. (2020)). To determine if the escarpment, or any other populations of M. virginiensis should be recognised as a separate species, we applied the unified species concept (de Queiroz 2007), which asserts that the only requirement for species status is its existence as a separately evolving metapopulation lineage. Under this concept, multiple properties can be used as evidence of lineage separation, though no one property is recognised as necessary for species status. In this study, quantitative and qualitative morphological differences and ploidy levels were investigated. The use of multiple properties as evidence of novel taxa is valuable in delimiting species within evolutionarily complex groups that have undergone rapid radiation, such as Micranthes (Stubbs et al. 2020b). Taxonomic history of M. virginiensis André Michaux described Saxifraga virginiensis in his Flora Boreali-Americana (1803, p. 269), as follows (translated from Latin): “The whole thing is a little pubescent; leaves oval, obtuse, somewhat petiolate, crenate; scape mostly aphyllous, paniculate, its branches with subsessile alternating flowers; calyx erect”. The range was given as rocky areas of Pennsylvania, Virginia and the mountains of the Carolinas. Michaux cited a drawing in Plukenet’s Phytographia (1691, plate 222, fig. 5; https://bibdigital.rjb.csic.es/viewer/13656/?offset=#page=106&viewer=picture&o=bookmark&n=0&q=), but stated that the panicle was not yet fully developed (“panicula nondum rite explicata”). Notably, Michaux’s description does not mention the stamens. Stamen length and filament shape are now known to be important characters in delimiting Southern Appalachian Micranthes (Lanning and Mathews 2019). The stamens of M. virginiensis are short enough to be hidden within the hypanthium and are not readily visible on herbarium specimens, including on the lectotype specimen from Michaux’s herbarium designated by Uttal (1984). 314 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Since Michaux’s original description, many varieties, forms and segregate taxa have been described. Most of these are currently considered synonyms of M. virginiensis due to a lack of distinct morphological differences and overlapping distributions. However, two described varieties, S. virginiensis var. californica (Greene) Jeps. (1905) and S. virginiensis var. subintegra Goodman (1950), have been elevated to species status. Micranthes californica (Greene) Small (1905) (= Saxifraga virginiensis var. californica (Greene) Jeps. 1901), is a Western North American species that is geographically disjunct from the rest of M. virginiensis and morphologically distinguished by differences in petal and sepal shape and orientation (Small 1896). Micranthes palmeri Bush (1928) (= Saxifraga virginiensis var. subintegra Goodman (1950)) occurs in Arkansas and Oklahoma, adjacent to the western edge of the range of M. virginiensis. It is distinguished from M. virginiensis by the entire leaf margins (vs. toothed), lack of glands on the inflorescence pubescence and glabrous pedicels (Steyermark 1959). Molecular phylogenetic analyses have also confirmed these taxa to be distinct lineages (Stubbs et al. 2020b). Micranthes palmeri is the sister taxon of M. virginiensis, while M. californica is less closely related, though still within the core Micranthes clade (Stubbs et al. 2020b). Some authors have recognised segregate taxa from M. virginiensis, based on perceived morphological differences associated with particular geographic areas (Sternberg 1810; Hooker 1833; Bush 1928), though these heterotypic species names have all subsequently been synonymised with M. virginiensis based on overlap in the characters. Willdenow (1804) described Saxifraga vernalis as synonymous with S. virginiensis in his original description, automatically rendering the former name as illegitimate in accordance with Article 52 of the International Code of Nomenclature for algae, fungi and plants (ICN, Turland et al. 2025). However, Hooker (1833) re-described S. vernalis (Hooker’s name illegitimate as a later homonym of Willdenow’s name) as distinct from S. virginiensis, based on differences in the inflorescence — the flower arrangement of S. vernalis forms an imperfect corymb or thyrse that contrasts with the sessile, alternate and somewhat unilateral flowers on the branches of the panicle of S. virginiensis. Yet, on the plant in Plukenet’s illustration of S. virginiensis, the panicle appears to match Hooker’s description and his illustration of S. vernalis. In the original description, Willdenow gives the range of S. vernalis as Pennsylvania, Virginia, and the Carolina mountains, whereas Hooker ascribes this species to Canada without mention of the range stated by Willdenow and he reports that he received samples of S. virginiensis mixed with S. vernalis (Hooker 1833). Saxifraga vernalis was not considered distinct from S. virginiensis by Torrey and Gray (1840) in their Flora of North America, as they noted that they perceived no differences between the two taxa. Hooker (1847) later relegated this taxon to a variety of S. virginiensis (as S. virginiensis var. vernalis, also illegitimate). Sternberg (1810), following Willdenow’s description of Saxifraga vernalis as synonymous with S. virginiensis, described S. elongata as different from S. vernalis, based on differences in the inflorescence. Saxifraga elongata, occurring in the Carolinas, has an elongated, unbranched scape with a cluster of small branches at the apex that contrasts with the branching scape of S. vernalis. Hooker (1833) considered S. elongata a variety of S. vernalis. Haworth (1803) first described Saxifraga pilosa as a distinct species, based on the pilose nature of the entire plant and the obtusely dentate leaves 315 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes and he later (1821) indicated S. vernalis and S. virginiensis as synonyms of his Dermasea pilosa. Bush (1928) resurrected the name Saxifraga pilosa and recognised it as distinct from M. virginiensis, based on morphological and geographic differences. He described M. virginiensis as north-eastern, possessing a cyme inflorescence, sharply serrated leaves and multiple scapes, while the southern and mid-western S. pilosa was described as racemose, with obtusely dentate leaves and a short, solitary scape (Bush 1928). Steyermark (1959) opposed this split, arguing that, though there is variation in many characters of M. virginiensis, there is intergradation of the characters between the two regions and, thus, there is no justification for splitting the species. Saxifraga vernalis, S. elongata and S. pilosa are all currently considered synonymous with Micranthes virginiensis. There are no currently recognised varieties of M. virginiensis (FNA vol. 8, 2009), though numerous varieties have been described. Saxifraga virginiensis var. cicinnata Engl. (1872) is described from Pennsylvania and Canada, with the fruiting plants described as loosely paniculate, with elongate secondary branches surpassing the terminal flower and flowers in a cicinnate inflorescence (Engler 1872). Engler cited Hooker’s (1833) narrow interpretation of S. virginiensis as a synonym of his var. cicinnata. Another variety, Saxifraga virginiensis var. cuneata Farw. (1944) was described, based on an apparent discrepancy in the descriptions of S. virginiensis in Gray’s New Manual (Gray et al. 1908, p. 446) and North American Flora (Small 1905, p. 140) — Gray’s New Manual describes obovate or oval-spatulate leaves and purplish follicles, whereas North American Flora describes ovate, oval or oblong leaves and green follicles. Farwell (1944) observed a population in Keeweenaw Co., Michigan that he felt best aligned with the Gray’s New Manual description and designated this S. virginiensis var. cuneata. Multiple forms of M. virginiensis have been described in New England. Within Essex Co., Massachusetts, three forms have been reported to exist in addition to typical M. virginiensis, two of which are only known from this County. Saxifraga virginiensis f. chlorantha (Oakes) Fernald (1917) has pale green petals contrasting with the typical white petals, as well as short hairs on the margins and backs of the petals. This form was found in Topsfield, Mass. and only known from a short description (Oakes 1847; Fernald 1917). Saxifraga virginiensis f. pentadecandra (Sterns) Fernald (1917) is apetalous and possesses 15 stamens, as opposed to 10, with five stamens taking the positions of the petals (Sterns 1887; Fernald 1917). It was first described on Manhattan Island in New York, but was later reported in Essex Co., Mass. as well. Saxifraga virginiensis f. glomerulata Fernald (1917) is distinguished from typical M. virginiensis by a lack of pedicels that cause the flowers to form glomerules and was described, based on three collections by A. S. Pease in Andover, Mass. from 1901–1902 (Fernald 1917). In addition to the Essex Co. forms, Saxifraga virginiensis f. plena Eames differs from typical M. virginiensis only in the doubled number of petals (Eames 1931). This form is described from one location in Litchfield County, Connecticut, though Eames noted other reports of double-flowered plants from Massachusetts, Pennsylvania and New York in his original description. Sterns (1887) suggested that these forms were likely teratological phenomena. Below, we present a list of all accepted synonyms of M. virginiensis, listed chronologically, with typification where possible: 316 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Saxifraga virginiensis Michx., Fl. Bor.-Amer. 1: 269. Mar 1803. Type: U.S.A. Haute Caroline et in rupib. Virginiae Pensylvaniae ad Schuykill, A. Michaux s.n. (lectotype, designated by Uttal (1984), p. 35 as “Type”: P! [IDC Michaux, microfiche no. 61, photo 8]). The lectotype specimen was also photographed by Blackwell et al. (2017, 2018) and is available at http://amphoreus.hpcc.uh.edu/ botcar/reference_images_2017a/ as file Michaux0563.tif. Saxifraga pilosa Haw., Misc. Nat. 157. Jul-Dec 1803. Type: U.S.A. Kentucky: limestone cliffs on the Ohio 6 miles above Louisville, C. Mohr s.n., 6 May 1855. (neotype here designated: US! [US03781685, http://n2t.net/ark:/65665/m3fc3ae0b1-82c8-4615-b5bb-a44db7d3af5a], mixed sheet, plant marked 2). Haworth’s specimens at OXF were mostly thrown away by Fielding (Stafleu and Cowan 1979); no original material could be located at OXF (Serena Marner, OXF, pers. comm.) or in the K digital collections. Saxifraga vernalis Willd., Hort. Berol. 1(4): 43. 1804, nom. illeg. superfl. Type: Hort. Bot. Berol. W., C.L. Willdenow s.n. (lectotype here designated: B-W! [B-W08394-010, http://plants.jstor.org/stable/10.5555/al.ap.specimen.b+- w+08394+-01+0]). Willdenow refers to a cultivated plant in the protologue, of which he includes an illustration. The lectotype specimen is incribed “S. vernalis” and “Hort. Bot. Berol. W”. Saxifraga elongata Sternb., Revis. Saxifrag.: 9. 1810. Type: U.S.A. Habitat in Carolina (holotype: Tab. IV in Revis. Saxifrag.: 9 (1810) [digital image!]). No original specimen that may serve as a lectotype was found among K digital collections where other Sternberg Saxifraga specimens reside. Dermasea pilosa Haw., Saxifrag. Enum.: 8. 1821. Type: Based on Saxifraga pilosa Haw. Dermasea elongata (Sternb.) Haw., Saxifrag. Enum.: 9. 1821. Type: Based on Saxifraga elongata Sternb. Saxifraga vernalis Hook., Fl. Bor. Am. 1: 248. 1829, nom. illeg. (later homonym; Hooker cites S. vernalis Willd as a synonym). Type: Hooker cited five syntypes from two localities: “Canada, and to the Mountains,” Lady Dalhousie. W. Sheppard, Esq. Dr. Richardson. Drummond; “On the Columbia, and from Fort Vancouver to the Kettle Falls,” Douglas. As of this date, none of these specimens has been located at K for lectotypification (Alan Paton, K, pers. comm.). Saxifraga virginiensis var. vernalis (Willd.) Hook., London J. Bot. 6: 231. 1847. Type: Based on Saxifraga vernalis Hook. Saxifraga virginiensis var. chlorantha Oakes Mag. Hort. Bot. 13: 218. 1847. Type: U.S.A. Massachusetts: Topsfield, 1842 (holotype: unknown, not at GH [Anthony Brach, HUH, pers. comm.], where Oakes’ herbarium was transferred from BSN (Stafleu and Cowan 1979). We decline to select a neotype at this time pending a search for duplicates at other herbaria. Saxifraga virginiensis var. cicinnata Engl., Monogr. Saxifraga 145. 1872. Type: Engler cited three syntypes from Pennsylvania, Saskatchewan and Montreal, Canada. Engler’s herbarium at B was mostly destroyed (Stafleu and Cowan 1979), although duplicates may exist at other herbaria. We decline to select a neotype at this time pending further investigation to confirm the unavailability of original material. Saxifraga virginiensis var. pentadecandra Sterns, Bull. Torrey Bot. Club 14: 124. 1887. Type: U.S.A. New York: New York Co. Near High Bridge [about 160th St.], N.Y. Island [Manhattan], Apr 1887, E.E. Sterns s.n. (lectotype here 317 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes designated: NY! [NY03227809, https://sweetgum.nybg.org/science/vh/ specimen-details/?irn=4959853]). Two collections are on the sheet, the lectotype is on the right. Micranthes virginiensis (Michx.) Small, Fl. S.E. U.S.: 501. 1903. Type: Based on Saxifraga virginiensis Michx. Saxifraga virginiensis f. elongata (Sternb.) Engl. & Irmsch., Pflanzenr. (Engler) 4, Fam. 117, 1(Heft 67): 41. 1916. Type: Based on Saxifraga elongata Sternb. Saxifraga virginiensis f. cicinnata (Engl.) Engl. & Irmsch., Pflanzenr. (Engler) 4, Fam. 117, 1(Heft 67): 42. 1916. Type: Based on Saxifraga virginiensis var. cicinnata Engl. Saxifraga virginiensis f. chlorantha (Oakes) Fernald, Rhodora 19: 143. 1917. Type: Based on Saxifraga virginiensis var. chlorantha Oakes. Saxifraga virginiensis f. glomerulata Fernald, Rhodora 19: 143. 1917. Type: U.S.A. Massachusetts: Prospect Hill, Andover, 24 May 1902, A.S. Pease 671 (holotype: NEBC! [NEBC00348793, https://plants.jstor.org/stable/10.5555/ al.ap.specimen.nebc00348793]). Saxifraga virginiensis f. pentadecandra (Sterns) Fernald, Rhodora 19: 144. 1917. Type: Based on Saxifraga virginiensis var. pentadecandra Sterns. Micranthes pilosa (Haw.) Bush, Amer. Midl. Naturalist 11(5): 220. 1928. Type: Based on Saxifraga pilosa Haw. Saxifraga virginiensis f. plena Eames, Rhodora 33(392): 169. 1931. Type: U.S.A. Connecticut: Kent, Litchfield County, on a ledge with several similar plants, 3 May 1908, Hugh Mosher s.n. (holotype: GH! [GH00575185, https://s3.amazonaws. com/herbaria4/NEVP-Images/2014/2014-03-17-190008/GH00575185.jpg]) Saxifraga virginiensis var. cuneata Farw., Pap. Michigan Acad. Sci. 30, pt. 1: 61. 1944. Type: U.S.A. Michigan: Keweenaw County, Lookout Range, exposed rocks, 13 June 1940, O.A. Farwell 12254 (holotype: BLH! [BLH0000313, http:// plants.jstor.org/stable/10.5555/al.ap.specimen.blh0000313]). Spatularia virginiensis (Michx.) Á.Löve & D.Löve, Taxon 31(2): 345. 1982, as ‘Spathularia’. Type: Based on Saxifraga virginiensis Michx. Materials and methods Plant collections In late winter and early spring of 2022 and 2023, we collected living plant specimens in pre-flowering condition (overwintering rosettes) from 37 populations (at least two individuals per population) of Micranthes virginiensis, including the atypical Blue Ridge escarpment populations identified by Lanning and Mathews (2019), hereafter referred to as “Gap Creek” and “Wadakoe Mountain” (Suppl. material 1: table S1). We also collected from populations of other south-eastern U.S.A. Micranthes species, including M. careyana, M. palmeri, M. micranthidifolia (Haw.) Small and M. petiolaris (Fig. 1; Suppl. material 1: table S1). Plants were potted and grown in the Western Carolina University greenhouse until flowering stalks formed. We removed young flower buds and placed them in vials containing Carnoy’s solution (3:1 95% ethanol:glacial acetic acid) for 24 hours, after which we replaced the solution with 70% ethanol. Vials were placed in a -20 °C freezer for later use in anther squashes for chromosome counts. The potted plants were grown until full anthesis, harvested and pressed as voucher 324 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes −5 0 5 escarpment virginiensis Species Value escarpment virginiensis Figure 4. Violin plot depicting scores of an LDA of Micranthes virginiensis and the escarpment populations. Escarpment refers to the Gap Creek and Wadakoe Mountain populations. Dataset includes flower characters and plant height. Table 1. Predicted classifications of Micranthes virginiensis and escarpment samples, based on LDA. escarpment M. virginiensis escarpment 15 0 M. virginiensis 0 24 Table 2. Factor loadings for each character used in LDA of M. virginiensis and escarpment samples. Character Loading Hypanthium length 1.09 Stamen length -2.35 Petal length 0.20 Petal width -0.03 Pistil length -0.71 Plant height -0.29 the Gap Creek and Wadakoe Mountain escarpment populations from M. virginiensis. These two characters sorted the samples along the first and second axes (LD1 = 89.59%; LD2 = 10.41%), though they were negatively correlated with each other. Pistil length somewhat sorted the escarpment individuals from the 325 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Figure 5. Principal Components Analysis of specimens of Micranthes virginiensis, M. careyana and the escarpment populations. Escarpment refers to the Gap Creek and Wadakoe Mountain populations. Dataset includes flower characters and plant height. Hypanthium.Length Stamen.Length Petal.Length Petal.Width Pistil.Length Plant.Height..cm. −2 0 2 −4 −2 02 PCA 1 (44.56%) PCA 2 (24.94%) careyana escarpment virginiensis other groups on the second axis and the other characters (petal length, petal width and plant height) did not sort the samples at all. The model was able to accurately predict the group for each sample (Table 3). The null hypothesis of PERMANOVA, that the centroid and dispersion are equal amongst groups, was rejected (p = 0.001), indicating that the centroid and/or the dispersion are different amongst groups. The dispersion test found no significant differences in the dispersion of values amongst groups (p = 0.94), indicating that the groups are significantly different from one another based on location. An additional PCA conducted with fruit characters and plant height from M. virginiensis images from SERNEC (not shown) indicated minimal to no relationship between the size of the fruit and plant height. There are no gaps in the values for fruit length that might indicate multiple distinct groups and fruit size does not appear to be related to geographic area (Suppl. material 1: table S5). Our data indicated that the Gap Creek and Wadakoe Mountain individuals typically have significantly larger fruits than M. virginiensis (2.51–5.56 mm, mean = 4.26 mm vs. 1.89–5.59 mm, mean = 3.51 mm; p = 0.01); however, there was overlap amongst the samples (Fig. 7). We found M. careyana to have fruits of 2.68–4.96 mm (mean = 3.83) and all values fell close to the normal range for M. careyana (3–5 mm, mean = 3.61 mm; Lanning and Mathews (2019)). Lanning and Mathews (2019) found that the fruits of M. careyana were larger than the fruits of M. virginiensis; however, they did not sample from throughout the range of the species. Our data indicated the contrary – M. virginiensis fruits are often the same size or even larger than M. careyana. The fruit sizes 326 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Hypanthium.Lengt h Stamen.Length Petal.Length Petal.Width Pistil.Length Plant.Height..cm. −5.0 −2.5 0.0 2.5 −10 −5 0 5 10 LD1 (89.59%) LD2 (10.41%) careyana escarpment virginiensis Figure 6. Linear Discriminant Analysis of specimens of Micranthes virginiensis, M. careyana and the escarpment populations. Escarpment refers to the Gap Creek and Wadakoe Mountain populations. Dataset includes flower characters and plant height. Ellipses represent 95% confidence intervals for the group centroids from the discriminant function. of M. careyana and the Gap Creek and Wadakoe Mountain individuals were not significantly different (p = 0.294). We summarise the diagnostic morphological characters that may be used to distinguish amongst M. virginiensis, M. careyana and the escarpment populations in Table 4. In all multivariate analyses, individuals from regions containing taxa now synonymised with M. virginiensis were found to fall within the primary cluster of M. virginiensis samples, confirming the synonymisation, with the caveat that many of these taxa were described, based on discrete characters that were not included in the multivariate analyses, such as branching pattern. After examining discrete characters on herbarium specimens from throughout the range, including all regions from where the synonymised taxa were described, we found no evidence for the recognition of any of these taxa (Suppl. materal 1: table S3). Chromosome counts Chromosome counts were obtained from meiotic pollen mother cells for individuals from 24 populations of M. virginiensis, three populations of M. careyana, two populations of M. palmeri, two populations of M. petiolaris and one population of M. micranthidifolia (Table 5, Fig. 8). The four populations of M. virginiensis sampled from the North Carolina Piedmont region are tetraploid (n = 19; Figs 1, 8b). In the Blue Ridge escarpment region, the morphologically distinct Gap Creek and Wadakoe Mountain populations are tetraploid (n = 19; Fig. 8a), as is a population consistent with the morphology of typical M. virginiensis, the Glassy Mountain, SC population (Fig. 1). In the same region, three morphologically typical M. virginiensis populations from this region are diploid (n = 10). Sampled individuals from populations from all other geographic regions throughout the range 327 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Table 3. Predicted classifications of Micranthes virginiensis, M. careyana and escarpment samples based on LDA. M. careyana escarpment M. virginiensis M. careyana 13 0 0 escarpment 0 15 0 M. virginiensis 0 0 24 Figure 7. Violin plot comparing fruit lengths of Micranthes virginiensis, M. careyana and the escarpment populations. Escarpment refers to the Gap Creek and Wadakoe Mountain populations. 0.2 0.4 0.6 careyana escarpment virginiensis Species Fruit Length (cm) careyana escarpment virginiensis Table 4. Diagnostic morphological characters used to distinguish amongst M. virginiensis, M. careyana and the escarpment populations. Taxon Stamen: Petal Stamen Length (mm) Hypanthium (mm) Sepal position at anthesis Petal Spots Anther Colour M. virginiensis < ½ petal length 0.91–2.04 Present (0.60–1.79) erect Absent Yellow Gap Creek/ Wadakoe > ½ petal length 2.24–3.57 Present (0.7–1.36) erect Absent Redorange M. careyana > ½ petal length 2.56–3.89 Absent spreading Present Redorange of this species are diploid (Table 5; Figs 1, 8d). In most Micranthes populations, supernumerary chromosomes were not observed, though we counted supernumeraries in some populations of M. virginiensis, M. careyana, M. petiolaris and M. micranthidifolia (Table 5). With the exception of the Gap Creek and Wadakoe Mountain populations, no morphological differences were observed between diploid and tetraploid M. virginiensis in qualitative observations and PCAs. 328 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes We are reporting the first counts for M. careyana and M. petiolaris as n = 10 (+ 0–3 supernumerary) and M. palmeri as n = 10 (Fig. 8c, e, f; Table 5). For M. micranthidifolia, we observed n = 11 (+ 0–1 supernumerary) chromosomes (Table 5), agreeing with the previously reported count of 2n = 22 (Brouillet and Elvander 2021). Given that many Micranthes species are n = 10 and that only one population of M. micranthidifolia was sampled in this study, it is possible that this species is actually n = 10 and that the count reported in this present study and in Brouillet and Elvander (2021) have mistaken a supernumerary Table 5. Meiotic chromosome counts for populations of Micranthes species done in this study. Species Voucher Country State/Province County Chromosome Count n (+ supernumeraries) Micranthes virginiensis Hall 9 USA AL Jefferson 10 Hall 6 USA AR Pulaski 10 Hall 41 USA CT New Haven 10 Hall 10 USA GA Fulton 10 Hall 22 USA KY Todd 10 Hall 38 USA MD Montgomery 10 Hall 39 USA MI Marquette 10 Hall 11 USA MS Clay 10 Hall 1 USA NC Polk 10 Hall 2 USA NC Polk 10 Hall 46 USA NC Polk 10 Hall 5 USA NC Durham 19 Hall 34 USA NC Chatham 19 Hall 50 USA NC Mecklenburg 19 Hall 51 USA NC Montgomery 19 Hall 12 USA NJ Somerset 10 Hall 4 USA SC Pickens 19 (+3) Hall 19 USA SC Spartanburg 10 Hall 21 USA TN Davidson 10 (+1) Hall 35 CAN ONT Lennox 10 Hall 7 USA VA Powhatan 10 Hall 36 USA VA Floyd 10 Micranthes sp. Hall 3 USA SC Greenville (Gap Creek) 19 (+0-4) Hall 14 USA SC Pickens (Wadakoe Mtn.) 19 M. careyana Hall 31 USA NC Macon 10 Hall 20 USA TN Knox 10 (+3) Hall 32 USA NC McDowell 10 M. palmeri Hall 8 USA AR Conway 10 Hall 16 USA MO Douglas 10 M. petiolaris Hall 30 USA NC Macon 10 (+0-3) Hall 47 USA NC Ashe 10 M. micranthidifolia Hall 15 USA NC Jackson 11 (+0-1) 329 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Figure 8. Images of chromosomes in various stages of meiosis from six Micranthes populations. a. Micranthes sp. n = 19 (+1). Greenville Co., SC (Gap Creek). Prophase I; b. M. virginiensis n = 19. Chatham Co., NC. Prophase II; c. M. petiolaris n = 10. Macon Co., NC. Anaphase I; d. M. virginiensis n = 10. Polk Co., NC (Melrose). Anaphase I; e. M. palmeri n = 10. Conway Co., AR. Prophase I; f. M. careyana n = 10 (+3). Knox Co., TN. Prophase I. Images are from just one plane of focus and, thus, relative sizes of chromosomes may not be accurately reflected in each image. 330 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Figure 9. Comparison of flowers of Micrathes scopularum and related species. a. Typical M. virginiensis flower. Glassy Mountain, SC.; b. M. scopularum flower. Gap Creek, Greenville Co., SC.; c. M. scopularum flower. Wadakoe Mountain, Pickens Co., SC.; d. Typical M. careyana flower. Swain Co., NC. Scale bars: 2.5 mm. chromosome for an A chromosome. However, since there are now multiple accounts of n = 11 chromosomes, this should remain the accepted count for M. micranthidifolia, though further investigation may be warranted. Taxonomic treatment Micranthes scopularum Hall, Lanning & Mathews, sp. nov. urn:lsid:ipni.org:names:77373282-1 Figs 9b, c, 10, 11 Diagnosis. Micranthes scopularum most closely resembles M. virginiensis, but differs in having longer stamens (2.24–3.57 mm long vs. 0.91–2.04 mm long) that are greater than half the length of the petals (vs. less than half the length of the petals), that are exserted from the petals (vs. included within the petals) and red-orange anthers (vs. yellow). Type. United StateS of america. South Carolina, Pickens County, moss-covered seepage rocks of waterfall on Wadakoe Mountain, 34.98221°N, 82.84356°W, elev. 340 m, 18 Mar 2023, fl., Tara Hall 52 (Holotype: WCUH (WCUH0034593; Fig. 11); isotypes: CLEMS, GA, NCU, WCUH). 331 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Description. Acaulescent, short-rhizomatous herbs; caudex scaly; roots fibrous. Flowering stems erect, leafless, 12–26 cm high. Leaves membranaceous, basally disposed, petiolate; petioles (0.3–)0.7–2.8 cm; blade shape variable, ovate, elliptic, orbicular, quadrate or obovate, 0.9–4.2 cm long, 0.7–2.3 cm wide, upper surfaces sparsely hispid or strigose with uniseriate trichomes, lower surfaces pubescent with multiseriate trichomes; apices acute to obtuse, bases cuneate to truncate; margins crenate to serrate, teeth mucronulate. Inflorescences lax, bracteate thyrses with monochasial subunits, with stipitate-glandular hairs on scape, branches and pedicels; bracts linear to elliptic, 0.6–2 cm long; bracteoles linear, 2–6 mm long. Flowers radially symmetric, pedicellate; pedicels 3–20 mm long; hypanthium ca. 1 mm long; calices green, shortly synsepalous, sepals, 1–2 mm long, broadly ovate, apices obtuse, erect to barely spreading at anthesis; corollas apopetalous; petals white, lacking spots, oblong, spreading at anthesis, 3.0–5.0 cm long, 1–2 cm wide, apices obtuse. Stamens 3–5 mm long; filaments tapering to the apex; anthers reddish-orange. Gynoecium superior, bicarpellate, glabrous, 3.5–5.0 mm long; ovary basally syncarpellous; styles and stigmas 2, slightly divergent; stigmas capitate. Capsules smooth, green, the 2 valves follicle-like, widely divergent, fused only at base, dehiscing introsely, each valve 3.5–6.0 mm long, 2.0–2.5 mm wide, styles and stigmas persistent; seeds numerous, brown, ellipsoid, tuberculate, ca. 0.5 mm long. Figure 10. Micranthes scopularum plant and habitat photos. From upper left to right: Flowers at anthesis, showing spreading, unspotted petals, exserted pistils and stamens and red-orange anthers; plants growing on bryophyte-covered, seepy, vertical rock face at type locality on Wadakoe Mountain (photos by S. Tessell); plants showing basal rosettes and lax scapes. From lower left to right: cluster of plants growing on moss-covered rock above creek at Gap Creek locality; flowers with hand for scale; part of inflorescence with flowers in side view showing upright sepals and short hypanthium and a developing fruit showing the 2-carpellate, follicle-like capsule (photos by M. Lanning). 332 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Figure 11. Holotype specimen of Micranthes scopularum. Etymology. The epithet means of cliffs and rock faces, as found on the steep edge of a plateau, also known as an escarpment, the landform on which the new species is found. 333 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Distribution, habitat and ecology. This species is known from two populations on the southern Blue Ridge Escarpment in northwest South Carolina, ca. 340 m elevation, where it grows on moss-covered rocks within a rich cove forest on Wadakoe Mountain, both on private property and within a State Heritage Preserve and Wildlife Management Area in Pickens County, SC. and on mossy rocks in and around Gap Creek, near Marietta, within the Mountain Bridge Wilderness Area and Jones Gap State Park in Greenville County, SC. Phenology. Flowers from late February to early April and fruits in mid-April to early May. Preliminary conservation assessment. At this time, there are only two known populations of Micranthes scopularum, including Wadakoe Mountain, in Pickens Co., SC. (the several collection localities on the mountain are assumed to constitute the same population) and the Gap Creek watershed in Greenville Co., SC. Population sizes appear stable over the years that we have observed them, but numbers are unknown. Each population is located, at least in part, on stateowned public land protected and managed by the South Carolina Department of Natural Resources. The Gap Creek population was impacted by fallen trees and floodwaters caused by Hurricane Helene, which devastated many parts of this region on 26–27 September 2024, but the severity of the impact is unknown. Paratypes. U.S.A. South Carolina: Greenville Co. • Marietta: Gap Creek, ca. 0.25 mi (0.8 km) down Gap Creek Road off U.S. Route 25. 35.1641220°N, 82.475519°W. 18 Mar 2023, fl., Tara Hall 48, 54, 55, 56, 57, 58, 59 (CLEMS, NCU, WCUH). [same location] 6 May 2023, fr., Tara Hall 49, 74, 75, 76, 77, 78, 79, 80, 81, 82 (CLEMS, NCU, WCUH). Pickens Co. • Moss-covered seepage rocks of waterfall on Wadakoe Mountain (private), 34.98221°N, 82.84356°W, elev. 1114 ft (340 m), 19 April 2008, fr., M. Lanning 18 with P. McMillan • Cooler Property, seep on N-facing slope of Wadakoe Mountain, 34.98252°N, 82.8441°W, elev. 332 m. 18 Mar 2023, fl., S.M. Tessel 23031801 (CLEMS) • Jocassee Gorges Wildlife Management Area, west fork of ‘Cooler Creek’ on N slope of Wadakoe Mountain. 34.98203, -82.84414, elev. 348 m. 18 Mar 2023, fl. S.M. Tessel 23021802 (CLEMS). Identification key to M. scopularum and related species The following key has been revised from Lanning and Mathews (2019) to include the new species: 1 Sepals completely reflexed at anthesis; filaments clavate (use 10×) .......... ..................................................................................................M. caroliniana – Sepals upright to spreading at anthesis; filaments tapering to the apex (use 10×) ........................................................................................................2 2 Stamens included, 0.9–2.0 mm long, less than half the length of the petals; anthers yellow .................................................................. M. virginiensis – Stamens exserted, 2.2–3.9 mm long, greater than half the length of the petals; anthers red-orange ............................................................................3 3 Hypanthium absent; petals and sepals spreading at anthesis, petals each with two yellow spots ..................................................................M. careyana – Hypanthium present (0.7–1.4 mm long); petals and sepals upright at anthesis, petals not spotted ......................................................M. scopularum 340 PhytoKeys 267: 309–343 (2025), DOI: 10.3897/phytokeys.267.162132 Tara K. Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Ji Y, Liu C, Yang J, Jin L, Yang Z, Yang JB (2020) Ultra-barcoding discovers a cryptic species in Paris yunnanensis (Melanthiaceae), a medicinally important plant. 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Hall et al.: Taxonomy of Micranthes virginiensis and new species of Micranthes Wu W, Ng WL, Yang JX, Li WM, Ge XJ (2018) High cryptic species diversity is revealed by genome-wide polymorphisms in a wild relative of banana, Musa itinerans, and implications for its conservation in subtropical China. BMC Plant Biology 18: 194. https:// doi.org/10.1186/s12870-018-1410-6 Zhang Q, Zhao CZ, Dong XG, Ma XL, Hou ZJ, Li Y (2015) Relationship between flower size and leaf size, number of Stellera chamaejasme population of degraded alpine grassland along an altitude gradient. Shengtaixue Zazhi 34(1): 40. Zhang J, Wang YZ, Gao HK, Zuo Z, Yang S, Cai C (2020) Different strategies in biomass allocation across elevation in two Gentiana plants on the Yunnan-Guizhou Plateau, China. Journal of Mountain Science 17(11): 2750–2757. https://doi.org/10.1007/ s11629-020-6253-6 Supplementary material 1 Supplementary figure and tables Authors: Tara K. Hall, Luiz F. L. da Silveira, Max S. Lanning, Katherine G. Mathews Data type: docx Copyright notice: This dataset is made available under the Open Database License (http://opendatacommons.org/licenses/odbl/1.0/). The Open Database License (ODbL) is a license agreement intended to allow users to freely share, modify, and use this Dataset while maintaining this same freedom for others, provided that the original source and author(s) are credited. Link: https://doi.org/10.3897/phytokeys.267.162132.suppl1