AimEndemic species, characterised by limited geographic ranges, face a high risk of extinction. The neotropical region harbours diverse ecosystems and a substantial number of endemic species, thus identifying areas of high endemism is crucial for protecting unique and threatened species and ecosystems. Vascular epiphytes-nonparasitic plants that grow on other plants without contact with the soil-exhibit remarkable diversity in the neotropics, with 63% of the global total of ca. 31,000 epiphyte species found in this region. This study aims to describe the endemism centres for the five most species-rich families of vascular epiphytes.LocationNeotropics.TaxonTracheophyta.MethodsWe gathered information from free-access web repositories, specific epiphytic plant databases and scientific and grey literature on epiphyte species of the families Araceae, Bromeliaceae, Orchidaceae, Piperaceae and Polypodiaceae within the neotropical realm as defined by Morrone et al. (2022). Geographical ranges were calculated using minimum convex polygons for 11,446 species, accounting for about 70% of all epiphyte species in the neotropics. Narrow endemic species were defined as those within the first quartile of the density distribution of geographic range sizes within each family and we identified endemism centres for epiphyte species of the five families.ResultsOur study identified endemism centres for vascular epiphyte species in several biogeographic provinces, including Paramo, Cauca, Guatuso-Talamanca, Atlantic, Yungas and Puntarenas-Chiriqui. Orchidaceae, accounting for most of the analysed species (71%), drove the overall distribution pattern; however, endemism patterns varied among families.Main ConclusionsRegions with high epiphyte richness exhibited a greater proportion of endemic species, though the composition of epiphyte species varied considerably among regions. The endemism centres identified in this study could be prioritised as conserved and protected areas.

The Neotropical realm hosts some of the Earth’s most species-rich biodiversity hotspots, with vascular epiphytes significantly contributing to this diversity, regionally accounting for up to 39% of the vascular flora. However, many regions of the Neotropics where epiphytic species of restricted distribution are reported coincide with threatened ecosystems, such as the tropical montane cloud forest. Moreover, epiphytes may be especially vulnerable to land use and climate change impacts due to their dependence on host trees. We assessed the conservation status of vascular epiphytes in the Neotropics for the families that represent over 80% of the global epiphyte diversity (Araceae, Bromeliaceae, Orchidaceae, Piperaceae, and Polypodiaceae) and identified geographical centres of accumulation of threatened epiphyte species. We gathered information from free-access web repositories, specific epiphytic plant databases, and scientific and grey literature. We assessed the extinction risk of 11,446 epiphyte species following IUCN Red List guidelines, using Criterion B (geographic range size). We found nearly 60% (6,721 species) to be threatened, with 1,766 critically endangered (CR), 3,537 endangered (EN), and 1,418 vulnerable (VU). The threatened species are mainly found in the centres of endemism of vascular epiphytes in Central America, the northern Andes, and the Atlantic Forest. Our study emphasises that the centres of threatened species largely coincide with diversity hotspots, highlighting epiphytes as an especially vulnerable group that requires urgent conservation actions.

Two previously unrecognized species of Myrtaceae, Myrcia damaniensis and Eugenia tain, from the Western Caribbean coastal and swamp forests of Panama are named and described. Their conservation status is evaluated based on the categories and criteria of the IUCN.

In this article, the authors review the current and historic extent of the federally endangered Harrisia aboriginum, a cactus endemic to southwest Florida. The plant was first described to science as a species in the early 1900s, but is thought to have been known to the indigenous people of Florida in pre-Columbian times. Past and present surveys have revealed the current number of individual plants remaining in the wild to be relatively low, primarily due to habitat destruction. Without further intervention to bolster existing populations and create new ones in protected areas, H. aboriginum may be headed towards extinction in the wild. Fortunately, thanks to collaboration with local and national conservation partners, efforts are underway to bring the species back from the brink.

Abstract. Calyptranthes magna, a new species of Myrtaceae from Yasuní National Park (Orellana, Ecuador), is described and illustrated.

A new species of Cyrtopodium from Belize, C. vestitum, is described and illustrated. Its flowers are indistinguishable from those of Cyrtopodium macrobulbon, but the pseudobulbs are relatively shorter and thicker, ovoid ellipsoid, bearing proportionately more, densely packed internodes, and the leaves do not present an articulation, i.e., an abscission layer, between the sheath and the blade and are thus marcescent. A comparative anatomy study of this tissue is presented, contrasting its presence in C. macrobulbon and the lack thereof in the new species. This species should be considered Endangered (EN) because of its restricted geographical distribution in central Belize. An updated key to the species of Cyrtopodium from North America, the Caribbean, and Central America is also included.

Abstract—A new classification of the predominantly Neotropical tribe Myrteae is proposed to replace Berg’s three traditional subtribes, the Myrciinae, Eugeniinae, and Myrtinae. Nine subtribes are here proposed that are supported by molecular and morphological data. In addition to the three traditionally recognized but modified here, subtribe Pimentinae (originally described as Pimentoideae) is reinstated and five new subtribes are proposed: Blepharocalycinae, Decasperminae, Luminae, Pliniinae, and Ugninae. A key to the nine subtribes is followed by descriptions of each, listing genera included, approximate species numbers, general distribution patterns, and notes. The genera Feijoa O. Berg and Temu O. Berg are reinstated. Morphological structures of importance for classification of Myrteae subtribes are illustrated.

Eugenia has a pantropical distribution and comprises ca. 1000 species found mostly in the Neotropics. Recent DNA based phylogenies show that unusual flower morphology of 'eugenioid' collections, e.g. fused calices that open by tearing, consistently emerged within Eugenia. These results emphasize a demand to revaluate flower morphology in a phylogenetic context within the genus. A reassessment of calyx fusion in Eugenia and traditionally related genera is here focused on clarification of the systematic relevance of this apparently recurrent characteristic. Twenty-four Eugenia species with some level of calyx fusion in the bud were newly used (one nuclear and four plastid markers) in conjunction with a representative sample of previously sequenced species to recover a time-calibrated Eugenia phylogeny of 86 accessions. Development of the fused calyx was analysed using scanning electron microscopy, differing patterns were re-coded and subsequently phylogenetic character reconstruction was performed. Eugenia was recovered as monophyletic including the traditionally segregated genera Calycorectes and Catinga. Ancestral character reconstruction uncovered free calyx lobes as the ancestral condition. Five development patterns leading to calyx fusion are reported in Eugenia including species with apparently six petals, which contrast with the standard tetramerous flowers. This condition is interpreted as the petaloid pattern, where two external fused calyx lobes cover the bud while two internal calyx lobes are free and petaloid. The fused calyx condition is homoplastic and evolved independently, several times in Eugenia, as did the different development patterns. Data presented here show that systematic incongruence resulting from multiple, independent origins of the fused calyx in Eugenia is further aggravated by an inability to distinguish parallelism and convergence within the recovered patterns.

The summits of the tepuis (sandstone table mountains of the Neotropical Guayana region—Guayana Highlands, GH) have been considered valuable for palaeoecological studies due to their pristine nature, which emphasizes the role of natural (i.e. non-human) factors on ecological change. Anthropogenic fires, very frequent in the surrounding Gran Sabana (GS) uplands, have very rarely been documented in the GH, and are therefore not considered an important ecological factor in the high-tepui biome. This paper reports the palynological and charcoal results of a Late Holocene sequence from the summit of Uei-tepui (2104m elevation), where extensive signs of fire were recently observed. Since ~2000calyr BP, the landscape of the study site has been dominated by meadows with occasional shrubs and cloud forests, which underwent expansions and contractions driven by climate changes and fire. A major vegetation shift occurred in the mid-18th century, when a sustained increase in local fires favoured the expansion of the low and spreading Cyrilla racemiflora shrublands at the expense of meadows and forests. Uei-tepui fires most probably were the result of human activities and reached the summit under study from the GS uplands through the vegetated slopes that characterize this tepui. The mostly anthropogenic nature of these fires, especially the more recent ones, is supported by the initial occurrence of wetter conditions, and by its coincidence with significant social changes in the GS indigenous populations, mainly the European contact. The emergence of fire as a disturbing agent of the GH biome highlights the need for an effective management plan in the GS uplands, where the vast majority of present-day fires originate, and designed in collaboration with the indigenous communities. Proactive conservation measures are considered even more important under future warming projections in the area.

The Guayana Highlands (GH) constitute a highly diverse, but relatively poorly studied Neotropical biome, comprised of ∼50 flat-topped mountain summits (called tepuis). Previous studies based on warming forecasts for the region suggested that an upward displacement of environmental conditions of 500–700 m could occur by 2100, potentially resulting in the extinction of c. 50% of its endemic flora due to total habitat loss. To assess the ecological responses of the species to climate change, and select the appropriate conservation measures, long-term monitoring of the GH plant communities will be necessary. In this study, the baseline state for future comparisons was established for the best explored tepui in terms of its flora, Roraima-tepui (2810 m), through a floristic characterization of its different vegetation types. We also identified the environmental gradients underlying the major plant communities, and assessed the effects of human activities on the chemistry of soils and water at three field camps. Our results yielded five main community types: three meadows, one shrubland, and one forest, with their corresponding diagnostic species. The herbaceous communities were mainly influenced by the presence of flat sandy soils, with varying flooding capacity. Shrublands and forests were characterized by irregular organic soils with very low pH. Finally, pH values below 3 were measured on an organic soil of a field camp, although further studies will be necessary to attribute this deviation to human activities.

Conceveiba belizensis McPherson & B. Holst (Euphorbiaceae), a new species of Conceveiba Aubl., is described, differing notably from the similar C. guianensis Aubl. and C. rhytidocarpa Mull. Arg. in having staminate inflorescences unbranched (vs. paniculiform), staminate flowers with pedicels 4-9 mm long (vs. less than 2 mm) and staminodes much shorter than the stamens (vs. staminodes much longer than the stamens), and pistillate flowers sessile (vs. pedicels at least 2 mm long).

Two new species and a new combination for Steyerbromelia (Bromeliaceae: Navioideae) are presented. These novelties represent the first records of Steyerbromelia for Colombia. The new species, Steyerbromelia naquenensis and Steyerbromelia nukakii, were placed in Steyerbromelia based on the combination of their 3- or 4-divided inflorescences, presence of smooth posterior sepals, and ovate, short-appendaged ovules. Both species resemble each other and S. thomasii, which also occurs in the basin of the Upper Rio Negro. Steyerbromelia garcia-barrigae is transferred from Navia, despite the lack of petal appendages, because its morphological characteristics fit better the limits of Steyerbromelia. An updated description of this species is presented. We now consider Steyerbromelia to be a genus of nine species. Additionally, notes on the geographic distribution, vernacular names, conservation status, and taxonomic comments of the three species are provided, as well as a key to all of the species. Finally, a discussion on the difficulties to place these three species within a genus is presented to highlight the problems of generic delimitation of the subfamily Navioideae.

Climate change is forcing many plant species to shift their range in search of adequate environmental conditions, being localized endemic species particularly at risk on mountain summits. The Pantepui biogeographic province, a set of flat-topped mountain summits (called tepuis) of northern South America, contains both high plant diversity and a high degree of endemism. Previous studies based on warming projections for the area suggested that half of the Pantepui endemic flora would disappear due to habitat loss by 2100. In this study, we selected one of the best-explored tepuis, Roraima-tepui, to establish the baseline of diversity and endemism for comparisons with historical data and future monitoring surveys, aimed at testing the hypothesis of upward migration of plants in response to global warming. We also analysed floristic and physiognomic features of the Eastern Tepui Chain (ETC, the mountain range where Roraima is located), and the phytogeographic patterns of both the ETC and Pantepui. The Roraima summit contains 227 species, including 44 new records, 13 exotic species (some of them with high invasive potential), and at least one species new to science. At the ETC level, Roraima is the tepui with highest species richness and degree of endemism, and shows a relatively high floristic similarity with Kukenan and Ilu. Herbaceous species dominate over shrubs on these tepuis, Tramen and Maringma, whereas on Yuruani, Karaurin and Uei, they reach similar abundances. At the Pantepui level, endemic species have highly localized distribution patterns (17% local endemics). Conservation opportunities are evaluated in light of these results.

We present an integrative model predicting associations among epiphytism, the tank habit, entangling seeds, C₃ vs. CAM photosynthesis, avian pollinators, life in fertile, moist montane habitats, and net rates of species diversification in the monocot family Bromeliaceae. We test these predictions by relating evolutionary shifts in form, physiology, and ecology to time and ancestral distributions, quantifying patterns of correlated and contingent evolution among pairs of traits and analyzing the apparent impact of individual traits on rates of net species diversification and geographic expansion beyond the ancestral Guayana Shield. All predicted patterns of correlated evolution were significant, and the temporal and spatial associations of phenotypic shifts with orogenies generally accorded with predictions. Net rates of species diversification were most closely coupled to life in fertile, moist, geographically extensive cordilleras, with additional significant ties to epiphytism, avian pollination, and the tank habit. The highest rates of net diversification were seen in the bromelioid tank-epiphytic clade (D(crown) = 1.05 My⁻¹), associated primarily with the Serra do Mar and nearby ranges of coastal Brazil, and in the core tillandsioids (D(crown) = 0.67 My⁻¹), associated primarily with the Andes and Central America. Six large-scale adaptive radiations and accompanying pulses of speciation account for 86% of total species richness in the family. This study is among the first to test a priori hypotheses about the relationships among phylogeny, phenotypic evolution, geographic spread, and net species diversification, and to argue for causality to flow from functional diversity to spatial expansion to species diversity.

La familia Myrtaceae es reconocida en el Perú por presentar 20 géneros y 165 especies (Brako & Zarucchi, 1993; Ulloa Ulloa et al., 2004), la mayoría arbustos y árboles. En este trabajo reconocemos 39 especies y una variedad como endemismos en diez géneros. El género más rico en especies endémicas es Eugenia. Las Myrtaceae endémicas se encuentran principalmente en las regiones Bosques Húmedos Amazónicos y Mesoandina, entre los 100 y 3600 m de altitud. Seis especies endémicas se encuentran dentro del Sistema Nacional de Áreas Naturales Protegidas por el Estado.

PREMISE:Bromeliaceae form a large, ecologically diverse family of angiosperms native to the New World. We use a bromeliad phylogeny based on eight plastid regions to analyze relationships within the family, test a new, eight-subfamily classification, infer the chronology of bromeliad evolution and invasion of different regions, and provide the basis for future analyses of trait evolution and rates of diversification.METHODS:We employed maximum-parsimony, maximum-likelihood, and Bayesian approaches to analyze 9341 aligned bases for four outgroups and 90 bromeliad species representing 46 of 58 described genera. We calibrate the resulting phylogeny against time using penalized likelihood applied to a monocot-wide tree based on plastid ndhF sequences and use it to analyze patterns of geographic spread using parsimony, Bayesian inference, and the program S-DIVA.RESULTS:Bromeliad subfamilies are related to each other as follows: (Brocchinioideae, (Lindmanioideae, (Tillandsioideae, (Hechtioideae, (Navioideae, (Pitcairnioideae, (Puyoideae, Bromelioideae))))))). Bromeliads arose in the Guayana Shield ca. 100 million years ago (Ma), spread centrifugally in the New World beginning ca. 16-13 Ma, and dispersed to West Africa ca. 9.3 Ma. Modern lineages began to diverge from each other roughly 19 Ma.CONCLUSIONS:Nearly two-thirds of extant bromeliads belong to two large radiations: the core tillandsioids, originating in the Andes ca. 14.2 Ma, and the Brazilian Shield bromelioids, originating in the Serro do Mar and adjacent regions ca. 9.1 Ma.

Three new species of Eugenia (Myrtaceae) from Ecuador are described and illustrated: Eugenia ampla, E . prolongata, and E. sericifolia. Resumen. Se describen y se ilustran tres especies nuevas de Eugenia (Myrtaceae): Eugenia ampia, E. prolongata y E. sericifolia.

Two new species of Calyptranthes (Myrtaceae) are described and illustrated: Calyptranthes carinata from Peru and C. nervata from Ecuador.