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Omphalodes (Boraginaceae s.s., Cynoglosseae s.l.) comprises ca. 29 species of annual and perennial plants distributed in three main disjunct areas: Western Palearctic, Japan and SW of North America. This paper uses micromorphological and DNA data to re-assess the monophyly and taxonomy of the genus. Morphological characters of 15 species of Omphalodes and four closely-related genera were analysed using SEM. A total of 82 ITS and 68 trnL-trnF sequences were newly sequenced, including 14 species of Omphalodes and three genera of the tribe Cynoglosseae. Phylogenetic analyses of 57 genera (186 species) of Boraginaceae indicated that Omphalodes as currently circumscribed is formed by three independent lineages, which were supported by morphological characters of the fruit. As a result, and in the interest of a more natural classification, two new genera are described to accommodate Omphalodes scorpioides (Memoremea) from Europe and the Japanese species (Nihon). Memoremea is distinguished from all the other species previously included in Omphalodes by the apical attachment scar and the hollow nutlet margin. Nihon is easily discriminated by the abrupt change of margin ornamentation towards the nutlet aperture. We also provided a taxonomic treatment that proposes the lowest number of nomenclature changes, although six new combinations are required.

PREMISE OF THE STUDY:Long-distance dispersal (LDD) syndromes, especially endozoochory, facilitate plant colonization of new territories that trigger diversification. However, few studies have analyzed how epizoochorous fruits influence both range distribution and diversification rates. We examined the evolutionary history of a hyperdiverse clade of Boraginaceae (subfamily Cynoglossoideae, eight tribes, ~60 genera, ~1100 species) and the evolution of fruit traits. We evaluated the evolutionary history of diaspore syndromes correlated with geographic distribution and diversification rates over time. METHODS:Plastid DNA regions and morphological traits associated with dispersal syndromes were analyzed for 71 genera (226 species). We employed trait-dependent diversification analysis (HiSSE) and biogeographic reconstruction (Lagrange) using a time-calibrated phylogeny. KEY RESULTS:Our results indicate that (1) the earliest divergence events in Cynoglossoideae occurred in the central-northeastern Palearctic during the Paleogene (early to middle Eocene); (2) an epizoochorous trait (specialized hooks named glochids) is ancestral and has been maintained long term; and (3) glochids are correlated with increased diversification rates in two distantly related clades (Rochelieae and Cynoglossinae). Rapid speciation occurred for these two groups in the same area (central-eastern Palearctic) and same period (Oligocene-Miocene: Rochelieae, 30.82-13.69 mya; Cynoglossinae, 33.10-15.21 mya). Lower diversification rates were inferred for the remaining four glochid-bearing clades. CONCLUSIONS: One more example of "biogeographic congruence" in angiosperms is supported by a shared geographic (central-northeastern Palearctic) and temporal (28.60-21.59 mya, late Oligocene) opportunity window for two main clades' diversification. Epizoochorous traits (fruit glochids) had an effect in higher diversification rates only with the joint effect of other unmeasured factors.

Researchers in phylogenetic systematics typically choose a few individual representatives of every species for sequencing based on convenience (neighboring populations, herbarium specimens, samples provided by experts, garden plants). However, few studies are based on original material, type material or topotypic material (living specimens from the locality where the type material was collected). The use of type or topotypic material in phylogenetic studies is paramount particularly when taxonomy is complex, such as that of Antirrhinum (Plantaginaceae). In this paper, we used topotypic materials of Antirrhinum at the species level (34 species proposed by previous authors), 87 specimens representing the species distributions and >50,000 informative nucleotide characters (from ∼4,000 loci) generated by the genotyping-by-sequencing (GBS) technique: (i) to test two explicit taxonomic hypotheses widely followed by local taxonomic treatments; (ii) to robustly estimate phylogenetic relationships; (iii) to investigate the evolution of key morphological characters and biogeographic centers of differentiation. Two GBS phylogenies based on two datasets (87 localities and 34 topotypic specimens) revealed that: (1) Sutton’s (1988) taxonomic account is the most congruent with phylogenetic results, whereas division of Antirrhinum into three major clades disagrees with Rothmaler’s (1956) infrageneric classification; (2) monophyly of populations currently included in the same species is primarily supported; (3) the historically recognized Antirrhinum majus group is not monophyletic; (4) sister-group relationships are robust for eight species pairs; (5) the evolutionary radiation of 26 species since the Pliocene is underpinned given a high rate of diversification (0.54 spp. Myr–1); (6) a geographic pattern of speciation is reconstructed, with northern Iberia as the center of early diversification followed by more recent speciation in southeastern Iberia; and (7) multiple acquisitions of key taxonomic characters in the course of Antirrhinum diversification are strongly supported, with no evidence of hybridization between major clades. Our results also suggest incipient speciation in some geographic areas and point to future avenues of research in evolution and systematics of Antirrhinum.

Biogeographic dispersal is supported by numerous phylogenetic results. In particular, transoceanic dispersal, rather than vicariance, is suggested for some plant lineages despite current long distances between America and Europe. However, few studies on the biogeographic history of plants have also studied the role of diaspore syndromes in long‐distance dispersal (LDD). Species of the tribe Omphalodeae (Boraginaceae) offer a suitable study system because the species have a wide variety of diaspore traits related to LDD and different lineages conform to patched worldwide distributions on three distant continents (Europe, America and New Zealand). Our aim is to reconstruct the biogeographical history of the Omphalodeae and to investigate the role of diaspore traits favoring LDD and current geographic distributions. To this end, a time‐calibrated phylogeny with 29 of 32 species described for Omphalodeae was reconstructed using biogeographical analyses (BioGeoBEARS, Lagrange) and models (DEC and DIVA) under different scenarios of land connectivity. Character‐state reconstruction (SIMMAP) and diversification rate estimations of the main lineages were also performed. The main result is that epizoochorous traits have been the ancestral state of LDD syndromes in most clades. An early diversification age of the tribe is inferred in the Western Mediterranean during late Oligocene. Colonization of the New World by Omphalodeae, followed by fast lineage differentiation, took place sometime in the Oligocene‐Miocene boundary, as already inferred for other angiosperm genera. In contrast, colonization of remote islands (New Zealand, Juan Fernández) occurred considerably later in the Miocene‐Pliocene boundary.

Traditional classification of speciation modes has focused on physical barriers to gene flow. Allopatric speciation with complete reproductive isolation is viewed as the most common mechanism of speciation. Parapatry and sympatry, by contrast, entail speciation in the face of ongoing gene flow, making them more difficult to detect. The genus Iberodes (Boraginaceae, NW Europe) comprises five species with contrasting morphological traits, habitats and species distributions. Based on the predominance of narrow and geographically distant endemic species, we hypothesized that geographical barriers were responsible for most speciation events in Iberodes. We undertook an integrative study including: (i) phylogenomics through restriction-site-associated DNA sequencing (RAD-seq), (ii) genetic structure analyses, (iii) demographic modelling, (iv) morphometrics, and (v) climatic niche modelling and niche overlap analysis. The results revealed a history of recurrent progenitor-derivative speciation manifested by a paraphyletic pattern of nested species differentiation. Budding speciation mediated by ecological differentiation is suggested for the coastal lineage, deriving from the inland widespread Iberodes linifolia during the Late Pliocene. Meanwhile, geographical isolation followed by niche shifts are suggested for the more recent differentiation of the coastland taxa. Our work provides a model for distinguishing speciation via ecological differentiation of peripheral, narrowly endemic I. kuzinskyanae and I. littoralis from a widespread extant ancestor, I. linifolia. Ultimately, our results illustrate a case of Pliocene speciation in the probable absence of geographical barriers and get away from the traditional cladistic perspective of speciation as producing two species from an extinct ancestor, thus reminding us that phylogenetic trees tell only part of the story.

Molecular studies have recently led to major changes to the systematics of Boraginaceae and changed our perception of fruit morphology, previously used as the most important character in Boraginaceae classification. Navel-shaped nutlets as the key character for Omphalodes turned out to be highly homoplasious, thus the genus was revealed to be polyphyletic. After the recent reclassifications, the genus Omphalodes is still left paraphyletic, since the remaining taxa correspond to two different lineages: a clade of essentially Mediterranean perennials including the type species (O. verna) and a clade with the annual to subperennial North American taxa including the genus Mimophytum. We here advocate transferring all taxa of the North American clade into the genus Mimophytum, subdividing the genus Omphalodes into morphologically coherent and monophyletic entities. Mimophytum was initially removed from Omphalodes based on its glochidiate nutlets, but this character state does not define a monophyletic entity. In overall morphology, the redefined genus Mimophytum is highly homogeneous and easily differentiated from the other clades: it has a lax growth habit, and leaves are long-petiolate, abruptly contracted at the base into a more or less cordate base, and with a fine pubescence of erect trichomes. After the proposed rearrangements, only O. erecta remains as a problematic species whose systematic placement is still to be found out.

Carex subg. Uncinia (Cyperaceae) constitutes one of six currently recognized Carex subgenera. This subgenus is mainly distributed on the American continent and in the Pacific region, and it is the only subgenus almost entirely absent from the Old World and primarily diversified in the Southern Hemisphere. It includes some of the few Carex species with clear epizoochoric traits: the representatives of C. sect. Uncinia possess utricles with an exserted and hooked rachilla that allows the diaspores to attach to feather or hair. We performed phylogenetic (ITS, ETS‐1f, matK), biogeographic, and ancestral state reconstruction analyses to elucidate the systematic structure, origin and dispersal routes, and major morphological evolutionary patterns of the different lineages within the subgenus. Our phylogenetic reconstructions revealed that the subgenus comprises seven different clades that mostly match previously recognized sections. One of the clades, however, represents a new section described herein as C. sect. Wheelerianae. Unispicate lineages evolved repeatedly from ancestors bearing multispicate inflorescences, while the presence of a rachilla, often pictured as a plesiomorphy in Carex, seems to have developed four independent times in the evolution of C. subg. Uncinia. The origin of the subgenus dates back to the beginning of the Miocene, probably in North America from where it colonized the Southern Hemisphere. It first dispersed to South America during the Early Miocene. Later, in the Middle Miocene, representatives of C. sect. Uncinia would reach the Pacific Southwest region (New Zealand, Australasia) from South America in at least two independent dispersal events. The vast majority of the biogeographic events seem to be explained by long‐distance dispersal. The remarkable dispersal ability of C. sect. Uncinia enabled by the hooked rachilla has allowed it to reach remote archipelagos in the Pacific and Subantarctic regions, probably bird‐mediated.