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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]

Aim Pacific biogeographical patterns in the widespread plant genus Melicope J.R. Forst. & G. Forst. (Rutaceae) were examined by generating phylogenetic hypotheses based on chloroplast and nuclear ribosomal sequence data. The aims of the study were to identify the number of colonization events of Melicope to the Hawaiian Islands and to reveal the relationship of Hawaiian Melicope to the Hawaiian endemic genus Platydesma H. Mann. The ultimate goal was to determine if the Hawaiian Islands served as a source area for the colonization of Polynesia. Location Nineteen accessions were sampled in this study, namely eight Melicope species from the Hawaiian Islands, four from the Marquesas Islands, one species each from Tahiti, Australia and Lord Howe Island, two Australian outgroups and two species of the Hawaiian endemic genus Platydesma. To place our results in a broader context, 19 sequences obtained from GenBank were included in an additional analysis, including samples from Australia, Papua New Guinea, New Zealand, Southeast Polynesia and Asia. Methods DNA sequences were generated across 19 accessions for one nuclear ribosomal and three chloroplast gene regions. Maximum parsimony analyses were conducted on separate and combined data sets, and a maximum likelihood analysis was conducted on the combined nuclear ribosomal and chloroplast data set. A broader nuclear ribosomal maximum parsimony analysis using sequences obtained from GenBank was also performed. Geographic areas were mapped onto the combined chloroplast and nuclear ribosomal tree, as well as onto the broader tree, using the parsimony criterion to determine the dispersal patterns. Results Phylogenetic analyses revealed that Platydesma is nested within Melicope and is sister to the Hawaiian members of Melicope. The Hawaiian Melicope + Platydesma lineage was a result of a single colonization event, probably from the Austral region. Finally, Marquesan Melicope descended from at least one, and possibly two, colonization events from the Hawaiian Islands. Main conclusions These data demonstrate a shifting paradigm of Pacific oceanic island biogeography, in which the patterns of long-distance dispersal and colonization in the Pacific are more dynamic than previously thought, and suggest that the Hawaiian Islands may act as a stepping stone for dispersal throughout the Pacific. [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]

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]

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]

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]

The article discusses a study which integrated nrDNA (ITS, ETS) and cdDNA (3' trnK intron) sequence, microsatellite, and morphological data to revise the taxonomy of sandalwoods in the genus Santalum in the Hawaiian Islands. It was found that the population of Santalum freycinetianum from O'ahu are different from populations on Moloka'i, Lana'i and Maui. The study suggested that Santalum freycinetianum variety of pyrularium and Santalum ellipticum are best treated at specific rank as Santalum pyrularium.

Understanding the relationships within the Caryophyllaceae has been difficult, in part because of arbitrarily and poorly defined genera and difficulty in determining phylogenetically useful morphological characters. This study represents the most complete phylogenetic analysis of the family to date, with particular focus on the genera and relationships within the large subfamily Alsinoideae, using molecular characters to examine the monophyly of taxa and the validity of the current taxonomy as well as to resolve the obscure origins of divergent taxa such as the endemic Hawaiian Schiedea. Maximum parsimony and maximum likelihood analyses of three chloroplast gene regions (matK, trnL-F, and rps16) from 81 newly sampled and 65 GenBank specimens reveal that several tribes and genera, especially within the Alsinoideae, are not monophyletic. Large genera such as Arenaria and Minuartia are polyphyletic, as are several smaller genera. The phylogenies reveal that the closest relatives to Schiedea are a pair of widespread, largely Arctic taxa, Honckenya peploides and Wilhelmsia physodes. More importantly, the three traditional subfamilies (Alsinoideae, Caryophylloideae, and Paronychioideae) are not reflective of natural groups; we propose abandoning this classification in favor of a new system that recognizes major lineages of the molecular phylogeny at the tribal level. A new tribe, Eremogoneae Rabeler & W.L.Wagner, is described here. [ABSTRACT FROM AUTHOR]