Adelinia and Andersonglossum (Boraginaceae), Two New Genera from New World Species of Cynoglossum

Recent phylogenetic evidence suggests that Cynoglossum (Boraginaceae), a cosmopolitan genus, is not monophyletic, but relationships among members of the genus remain uncertain. This is particularly the case for North American species of Cynoglossum. Utilizing DNA sequence data, a phylogeny has been reconstructed to investigate the evolutionary relationships among the New and Old World species of Cynoglossum and other members of Boraginaceae. The resulting phylogeny resolved that North American species of Cynoglossum are members of a clade distinct from the Old World species, and these North American species belong to two distinct lineages. Cynoglossum occidentale and C. virginianum are sister species, and C. grande is a member of a separate group. Given these evolutionary relationships in conjunction with diagnostic morphological features, two new genera are proposed for these species, Andersonglossum and Adelinia, with four name transfers: Andersonglossum boreale, Andersonglossum occidentale, Andersonglossum virginianum, and Adelinia grande. Andersonglossum bears sessile cauline leaves, pedicels recurved in fruit, and pollen with two shapes of pores and no transverse groove. In contrast, Adelinia develops petiolate cauline leaves, pedicels erect in fruit, and pollen with only one pore shape and a transverse groove. Keywords—Amsinckiinae, Cryptantha, molecular systematics, Oncaglossum, taxonomy. Cynoglossum L. (Boraginaceae) is a medium-sized genus with a cosmopolitan distribution (Zhu et al. 1995). The genus, which is the type of Cynoglosseae W. D. J. Koch, is characterized by heterocolpate pollen and glochidiate nutlets that bear submedial attachment to the gynobase. Recent phylogenetic work by Cohen (2011, 2014) and Weigend et al. (2013) has demonstrated that Cynoglossum, as it has been traditionally defined (e.g. Selvi and Sutorý 2012), is not monophyletic, and this is due to two factors. One is that multiple species from other genera, including Cynoglossopsis Brand, Lindelofia Lehm., Paracaryum Boiss., Rindera Pall., Pardoglossum Barbier &Mathez, Solenanthus Ledeb., Trachelanthus Klotzsch, Paracynoglossum Popov, and others, are nested among the Old World species of Cynoglossum. The second is that the few New World species of Cynoglossum are members of clades separate from that of the Old World species of the genus. Indeed, in the analyses of Weigend et al. (2013) the North American species represent an early-diverging group that colonized the continent prior to the explosive diversification of Cryptantha Lehm. ex G.Don and its relatives throughout western North and South America, and the South American species is a member of the clade that includes Omphalodes Mill. and Myosotidium Hook. The objective of the present study is to use plastid and nuclear ribosomal DNA regions to reconstruct a phylogeny of Cynoglossum and relatives in order to resolve relationships among North American species of the genus and relatives. Additionally, if upon critical analysis the North American species remain distinct from other members of Cynoglossum, then an appropriate taxonomic system that includes diagnostic morphological features will be constructed. Four species of Cynoglossum are native to North America. Using morphological evidence, Sutorý (2010) recently segregated the Mexican endemic C. pringlei Greenm. into the genus Oncaglossum Sutorý. This separation was later supported by phylogenetic data, with Oncaglossum resolved as sister to Amsinckiinae Brand. (Cryptanthinae of HasenstabLehman and Simpson [2012]), which includes Cryptantha and relatives (Cohen 2011, 2014). The other three North American species of Cynoglossum have been included in a phylogenetic analysis by Weigend et al. (2013). In their analysis, C. occidentale A. Gray and C. virginianum L. were sister species, and C. grande Douglas ex Lehm. was closely related, but the relationship was ambiguous. The clade of C. occidentale + C. virginianum and C. grande formed a trichotomy with members of Amsinckiinae, including Dasynotus daubenmirei I. M. Johnst. In 2012, Hasenstab-Lehman and Simpson reevaluated the taxonomy of Amsinckiinae (as Cryptanthinae) because their phylogenetic analyses provided evidence that Cryptantha and Plagiobothrys Fisch. & C. A. Mey. were not monophyletic. To this end, the authors revised the taxonomy for the subtribe, which now includes nine genera: Amsinckia Lehm., Cryptantha, Eremocarya Greene, Greeneocharis Gürke & Harms, Harpagonella A. Gray, Johnstonella Brand, Oreocarya Greene, Pectocarya DC. ex Meisn., and Plagiobothrys. The results of Cohen (2011, 2014) and Weigend et al. (2013) provide evidence that other NewWorld members of Cynoglosseae (e.g. Cynoglossum, Dasynotus I. M. Johnst., and Oncaglossum) are closely related to Amsinckiinae, but these relationships either remain ambiguous or have not been adequately examined. In order to elucidate phylogenetic relationships among these species, the current study includes all four North American species that have been members of Cynoglossum as well as other species that are putatively related to Amsinckiinae. Furthermore, given the isolated position of these North American members of Cynoglossum from other members of the genus, including the type species C. officinale L., it seems likely that these North American species will need to be transferred to other genera. Materials and Methods Taxon Sampling and Sequence Data—The present study includes 55 species (supplementary Appendix S1) from across Cynoglosseae. This sampling represents both morphological and geographic variation in the tribe. Sequence data from four DNA regions were included in the present study: two protein-encoding plastid DNA (cpDNA) regions (matK and ndhF), one cpDNA intergenic spacer (trnL-trnF), and the nuclear ribosomal DNA (nrDNA) internal transcribed spacer (ITS). Leaf material for new DNA isolations was obtained from individuals from wild populations. Additional sequence data for multiple species were obtained from GenBank. Appendix S1 includes GenBank numbers for all species in the present study as well as voucher information for new sequences.