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Evolutionary shifts in breeding system are thought to have played key roles in the diversification of many lineages of plants, including the evening primrose family (Onagraceae), which includes the genus Oenothera L. Diversification in Oenothera has been accompanied by frequent breeding system shifts, but it is not clear whether these differences are due to shared evolutionary history or reflect repeated independent adaptations to varying ecological conditions. In this study, we focus on "Subclade B," one of two primary clades within Oenothera, and combine phylogenetic reconstructions and breeding system data to evaluate evidence for multiple transitions to self-compatibility. This study includes 46 of the 58 named taxa (species and subspecies) of Oenothera Subclade B. Some taxa were sequenced in earlier analyses, available from GenBank, one was resampled here to add new sequences, and 28 taxa are newly sequenced here. We base our phylogeny on sequencing of portions of four chloroplast markers (rps16, ndhF, trnL-F, and rbcL) and two nuclear genes (ITS and ETS). We used pollination tests to verify or determine the breeding system of these taxa. Our phylogeny supports the current classification of Oenothera with minor changes and provides greater insight and clarity to the relationships of these species. Our results provide support for the monophyly of most of the sections in Oenothera Sub- clade B, as well as greater resolution for topology within sections Gaura (L.) W. L. Wagner & Hoch, Hartmannia (Spach) Wal- pers, Kneiffia (Spach) Walpers, and Megapterium (Spach) Walpers. Relationships among these monophyletic lineages, and the placement of sections Paradoxus W. L. Wagner and Peniophyllum (Pennell) Munz, and of the allopolypoid O. hispida (Benth.) W. L. Wagner, Hoch & Zarucchi, are not uniformly well-supported and need further clarification, but these phylogenetic uncertainties had minimal impact on the inference of transitions in self-compatibility in Subclade B. We use maximum likelihood, Bayesian inference and stochastic character mapping to estimate the minimum and maximum number of transitions necessary to explain the phylogenetic distribution of self-compatible lineages. Our results confirm at least 12 and possibly up to 15 independent transitions from self-incompatibility to self-compatibility in Oenothera Subclade B. This lability in breeding system, which is also seen broadly across Oenothera, lends strong support to the hypothesis that this trait plays a key role in the diversification of the genus. [ABSTRACT FROM AUTHOR]

Platydesma, an endemic genus to the Hawaiian Islands containing four species, has long been considered of obscure origin. Recent molecular phylogenetic studies have unequivocally placed Platydesma within the widespread genus Melicope as sister to the rest of the Hawaiian species of Melicope. This makes submerging Platydesma into Melicope necessary. We make the necessary new combinations: Melicope cornuta (Hillebr.) Appelhans, K.R. Wood & W.L. Wagner, M. cornuta var. decurrens (B.C.Stone) Appelhans, K.R. Wood & W.L. Wagner, M. remyi (Sherff) Appelhans, K.R. Wood & W.L. Wagner, and M. rostrata (Hillebr.) Appelhans, K.R. Wood & W.L. Wagner. An additional species that has been recognized within Platydesma should now be recognized under its original name M. spathulata A. Gray. All Hawaiian species belong to Melicope section Pelea. Our molecular phylogenetic studies also showed that in addition to merging Platydesma into section Pelea, five species described from New Caledonia need to be excluded from the section in order to achieve monophyly of section Pelea. [ABSTRACT FROM AUTHOR]

Melicope ( Rutaceae) is one of the largest plant genera on the Hawaiian Islands. We present here a detailed molecular phylogenetic analysis of the Hawaiian species of this genus and compare the results with the other genera of Hawaiian Rutaceae, Platydesma and Zanthoxylum. Four nuclear and two plastid markers were sequenced, with the goals of untangling phylogenetic relationships, inferring biogeographic events and comparing patterns of distribution among the three genera. Our results show that there were two colonization events ( Melicope + Platydesma, and Zanthoxylum) to the Hawaiian Islands, that Hawaiian Rutaceae have an Asian, Australian or Pacific origin and that there were two independent colonization events of Hawaiian Melicope lineages to the Marquesas Islands. The two most widely distributed Hawaiian Melicope spp. are not monophyletic and the current subgeneric classification of Hawaiian Melicope is highly artificial. On the Hawaiian Islands, Melicope and Zanthoxylum show contrasting biogeographic patterns, suggesting different patterns of dispersal. Melicope has a high percentage of single-island endemics suggesting low dispersal ability, whereas Zanthoxylum taxa tend to occur across multiple islands. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 174, 425-448. [ABSTRACT FROM AUTHOR]

During the preparation of the Vascular Flora of the Marquesas Islands three new species of Cyrtandra (Gesneriaceae) have come to light and are described herein: C. uapouensis W. L. Wagner & Lorence, C. uahukaensis W. L. Wagner & Lorence, and C. kenwoodii W. L. Wagner & A. J. Wagner. Amended descriptions of the eight previously described Marquesan species are also provided as well as a key to the species. With the description of these the new species Cyrtandra in the Marquesas Islands consists of 11 species, six of which have been included in recent molecular phylogenetic studies of Pacific Cyrtandra, and appear to have arisen from one original introduction. If the other five species are members of this Marquesas clade then Cyrtandra would represent the largest lineage of Marquesas vascular plants. Psychotria is largest genus in the Marquesas Islands with 13 species, but is thought to consist of three separate lineages. [ABSTRACT FROM AUTHOR]

Abstract: Circaea (Onagraceae) consists of eight species and six subspecies distributed in Eurasia and North America. The sister group of Circaea was recently shown to be Fuchsia, which comprises 107 species primarily distributed in montane Central and South America, including four species occurring in the South Pacific islands. Three plastid markers (petB–petD, rpl16, and trnL-F) and nrITS sequences from 13 of the 14 taxa of Circaea were sequenced and used to reconstruct the phylogenetic and biogeographic history of the genus. Parsimony and Bayesian analyses support that (1) Circaea is monophyletic; (2) the bilocular group is a weakly supported clade nested within the unilocular grade; (3) neither the C. alpina complex nor the C. canadensis complex is monophyletic; and (4) the western North American C. alpina subsp. pacifica diverged first in the genus. Divergence time estimates based on the Bayesian “relaxed” clock methods suggest that the earliest Circaea divergence occurred minimally at 16.17mya (95% HPD: 7.69–24.53mya). Biogeographic analyses using divergence–vicariance analysis (DIVA) and a likelihood method support the New World origin of Circaea. Three independent dispersal events between Eurasia and North America via the Bering land bridge were inferred within Circaea. Higher taxon diversity of Circaea in eastern Asia was probably caused by geologic and ecological changes during the late Tertiary in the Northern Hemisphere. [Copyright &y& Elsevier]

Abstract: The genus Cyrtandra is the largest in the Gesneriaceae family and is one of the most widely dispersed plant genera in southeast Asia and the Pacific. Species of Cyrtandra are morphologically diverse but characters are often homoplastic causing considerable difficulty in defining monophyletic classification units. In this study, we used molecular phylogenetic analysis of 88 taxa representing approximately 70 species to construct a well-resolved evolutionary hypothesis for Cyrtandra. Diversification rates analysis and ancestral range analysis were also conducted to infer timing of major lineage divergences and geographic origin of these lineages, principally among Pacific species. Using these data, we compared existing classification schemes to better understand the applicability of current taxonomy. Divergence time estimates support a diversification of the Pacific clade at approximately 20 MYBP. Although the origin of the Pacific lineage remains unresolved, ancestral range reconstruction analysis supports Fiji as the most likely “first-step” into the Pacific with subsequent dispersals to Hawai‘i, and other archipelagos. A greater Fiji–Samoa region, corresponding with Takhtajan’s Fijian Region, is implicated as a major Pacific region interface and possibly a center of origin for expansion of Cyrtandra throughout the Pacific. Among South Pacific taxa sampled, several supported clades in our evolutionary hypothesis are characterized by distinct morphological traits possibly warranting sectional rankings. Relationships among Hawaiian taxa are less resolved and the distributions of species within this clade do not consistently correspond to existing sectional rankings. More detailed, population-level research is needed to clarify these relationships. We argue that future sectional classifications should correspond with monophyletic lineages and that species-level relationships should be more closely studied within these lineages. [Copyright &y& Elsevier]

Cyrtandra comprises at least 600 species distributed throughout Malesia, where it is known for many local endemics and in Polynesia and Micronesia, where it is present on most island groups, and is among the most successfully dispersing genera of the Pacific. To ascertain the origin of the oceanic Pacific island species of Cyrtandra, we sequenced the internal transcribed spacers of nuclear ribosomal DNA of samples from throughout its geographical range. Because all oceanic Pacific island species form a well-supported clade, these species apparently result from a single initial colonization into the Pacific, possibly by a species from the eastern rim of SE Asia via a NW-to-SE stepping stone migration. Hawaiian species form a monophyletic group, probably as a result of a single colonization. The Pacific island clade of Cyrtandra dispersed across huge distances, in contrast to the apparent localization of the SE Asian clades. Although highly vagile, the Pacific clade is restricted to oceanic islands. Individual species are often endemic to a single island, characteristic of the ‘supertramp’ life form sensu Diamond (1974, Science 184:803–806). The evolution of fleshy fruit within Cyrtandra provided an adaptation for colonization throughout the oceanic Pacific via bird dispersal from a single common ancestor. [ABSTRACT FROM AUTHOR]

Cyrtandra (Gesneriaceae) is among the largest genera of flowering plants in the remote oceanic islands of the Pacific, with an estimated 175 species distributed across an area that extends from the Solomon Islands, east to the Marquesas Islands, and north to the Hawaiian Islands. The vast majority of species are single-island endemics that inhabit upland rainforests. Although previous molecular phylogenetic studies greatly advanced our understanding of the diversification of Pacific Cyrtandra , a number of uncertainties remain regarding phylogenetic relationships, divergence times, and biogeographic patterns within this large and widely dispersed group. In the present study, five loci (ITS, ETS, Cyrt 1, psb A- trn H, and rpl 32- trn L) were amplified and sequenced for phylogenetic reconstruction of 121 Cyrtandra taxa. Maximum likelihood and Bayesian inference confirmed that C. taviunensis from Fiji is sister to the remaining members of the Pacific clade. Dating analyses and ancestral area estimation indicates that the Pacific clade of Cyrtandra originated in Fiji during the Miocene ca. 9 mya. All major crown lineages within the Pacific clade appeared < 5 mya, coincident with the emergence of numerous Pacific islands and a subsequent increase in available habitat. The biogeographic history of Cyrtandra in the Pacific has been shaped by extinction, dispersal distance, and founder events. Biogeographic stochastic mapping analyses suggest that cladogenesis within Pacific Cyrtandra involved a combination of narrow (within-area) sympatry and founder events. A mean of 24 founder events was recovered between Pacific archipelagos, while a mean of 10 founder events was recovered within the Hawaiian archipelago. [ABSTRACT FROM AUTHOR]

We present the first detailed phylogenetic study of the genus Melicope , the largest genus of the Citrus family (Rutaceae). The phylogenetic analysis sampled about 50% of the 235 accepted species of Melicope as well as representatives of 26 related genera, most notably Acronychia and Euodia . The results based on five plastid and nuclear markers have revealed that Acronychia , Euodia and Melicope are each not monophyletic in their current circumscriptions and that several small genera mainly from Australia and New Caledonia need to be merged with one of the three genera to ensure monophyly at the generic level. The phylogenetic position of the drupaceous Acronychia in relation to Melicope , which has capsular or follicular fruits, remains unclear and Acronychia might be a separate genus or a part of Melicope . The seed coats of Melicope , Acronychia and related genera show adaptations to bird-dispersal, which might be regarded as key innovations for species radiations. Euodia and its relatives, which lack these adaptations, include only about 20 species while the Melicope – Acronychia group consists of about 340 species. The drupaceous genera Comptonella , Dutaillyea , Picrella and Sarcomelicope are nested within Melicope and need to be merged with Melicope . The expanded genus is a prime example of the artificial classification system of Engler, who defined Rutaceous subfamilies mainly based on gynoecial and fruit characters. [ABSTRACT FROM AUTHOR]