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Myrtaceae are a large family of trees and shrubs, including ca. 2500 species within the predominantly Neotropical and taxonomically problematic tribe Myrteae. Nearly 500 species of Myrteae are endemic to the Caribbean Islands Biodiversity Hotspot, but few have been represented in phylogenetic systematic studies to date. The major goals of this survey are to identify the main lineages of Myrteae present in the Greater Antilles and potential clades for further investigation. Specific objectives are to evaluate the monophyly and placement of the following: (1) the three genera of Myrtaceae considered endemic to the Caribbean Islands (Calyptrogenia, Hottea, Mitranthes); (2) Calycolpusand Pseudanamomissensu Bisse; and (3) Greater Antillean species of Plinia. To accomplish these aims, species of Myrtaceae representing all genera native to the Greater Antilles were sampled from across the region for placement within previously established phylogenetic frameworks for Myrteae and the large genus Eugenia. In total, 160 terminal taxa of Myrtaceae (89 Caribbean Islands endemics) were analyzed for this study. Phylogenetic inference was conducted by maximum parsimony and Bayesian methods on alignments of DNA sequence data from one nuclear (ITS) and three chloroplast (psbA‐trnH, ndhF‐rpl32, trnL‐trnF) regions. Results of both types of analysis were congruent with each other and with the major clades recovered in previous studies, but some conflict was observed between nuclear and chloroplast regions involving congeneric species. Calycorectes(= Hottea) ekmaniifrom eastern Cuba was found to be closely related to Calycolpuswithin subtribe Myrtinae. Subtribes Myrciinae, Pliniinae, Pimentinae (Pimenta and Psidium groups) and Eugeniinae contained other Greater Antillean species. Sampled species of Pliniafrom Cuba emerged within Myrciaria, and Mitrantheswas found to be non‐monophyletic. All sampled species of Eugeniaendemic to the Caribbean fell within E.sect. Excelsae(including Calycolpussensu Bisse), E.sect. Racemosaeand E.sect. Umbellataeexcept for E. cycloidea, which was associated with the Old World species of E.sect. Jossinia. Within Eugeniasect. Umbellatae, Caribbean species formed two major clades, designated C1 and C2, containing species of Calyptrogeniaand Hotteafrom southern Hispaniola,a polyphyletic Pseudanamomissensu Bisse and the Lathberry Clade, a novel group of Eugeniaspecies centered in Puerto Rico and the Virgin Islands. Calyptrogeniaand Hotteaspecies from southern Hispaniola are transferred to Eugeniaalong with Pseudanamomis nipensis, while Mitranthesspecies are transferred to Myrcia. Two additional combinations are made within Eugeniaand Pimentain accordance with the results, and lectotypes are designated as appropriate.

ABSTRACTSeven plant genera are regarded as endemic to Jamaica [Dendrocousinsia(seven species, Euphorbiaceae), Jacmaia(one species, Asteraceae), Odontocline(six species, Asteraceae), Portlandia(six species, Rubiaceae), Salpixantha(two species, Acanthaceae), Tetrasiphon(one species, Celastraceae) and Zemisia(one species, Asteraceae)]. A review pertinent to the taxonomy, distribution range, phylogenetics, conservation challenges and research updates of these genera is presented. We also provide an overview pertinent to biodiversity conservation policy and phytogeography of Jamaica. Half of the species placed in these genera have not been red-listed (sensuIUCN), and six of them are not in situconserved in protected areas. Tetrasiphonand D. lesterivar. glabratahave the highest conservation priority within these endemic genera. Taxonomic boundaries between species of Odontoclineare poorly understood, and there is a lack of phylogenetic data for this genus. None of these endemic genera have been the subject of population biology or population genetic studies. Phytochemical research has been performed on Portlandiaand the three genera of the Compositae. Among these endemic taxa only Z. discolorhas been reported to have ethnobotanical usage; however, the tea infusions made from leaves of this taxon may potentially cause cirrhosis. Extracts derived from leaves of Portlandiahave antitumour activity.

The nomenclature of Dendrocousinsia(Hippomaneae, Euphorbiaceae) is revised and we present four new taxonomic combinations within the genus. It comprises six species and one variety. Extensive field surveys were conducted and conservation assessments are presented based on the IUCN redlist system for threatened species. Three of the species are Critically Endangered as each of them has a very restricted distribution. The other three species are Vulnerable. There has been a long debate pertinent to the taxonomic placement of Dendrocousinsia. Until extensive phylogenetic studies are performed within the Hippomaneae we propose to maintain this group as a distinct genus and not as a section within Sebastiania. This study highlights Dendrocousinsiaas restricted to Jamaica with a high conservation priority because of its uniqueness and the Critically Endangered status of half of its species.

The article discusses the exploration of new areas in botanical research with an applied component, focusing on the extensive living collections of tropical plants at Fairchild Tropical Botanic Garden in South Florida. It says that some of the studies focus on natural plant products and their potential use in medicine, agriculture and taxonomy. It says that Florida International University cellular biologists and botanist developed three projects to research natural plant products.

Portlandia(Rubiaceae) is a genus endemic to Jamaica. The volatile organic constituents of P. albiflora, P. coccinea, P. grandiflora, P. latifoliaand P. proctoriiwere analyzed by headspace solid-phase microextraction (SPME) coupled with capillary mass spectrometry. The main constituents detected in these species are 1-penten-3-one, hexanal, (E)-2-hexenal, linalool, borneol and methyl salicylate. All species are rich in aliphatic aldehydes, mainly represented by (E)-2-hexenal, that range from 17% (P. latifolia) to 90% (P. coccinea) of total volatiles. The high content of aldehydes is characteristic to Portlandiaspecies and may serve as a chemical marker to differentiate Portlandiafrom related genera within the Rubiaceae.

The article discusses Fairchild's Cockpit Country project for the last remaining large forested tracts in the Caribbean known as the Cockpit Country. Collaborative work between Fairchild and the Institute of Jamaica have provided the foundation for the project to explore, study and analyze the flora of the Cockpit Country to support an integrated plant conservation strategy for the region and build research and management. It cites ongoing research on patterns of genetic variation in Jamaican plants especially those used for medicinal purposes.