Taxonomic revision of Rochefortia Sw. (Ehretiaceae, Boraginales)

Abstract Background Rochefortia is a small taxon of woody plants in the Ehretiaceae (Boraginales) exhibiting coriaceous leaves with cystoliths, small whitish flowers and drupaceous fruits containing four pyrenes. It shares the dioecious sex distribution with its sister group Lepidocordia and can be delimited from the latter (and all other Ehretiaceae) by the presence of thorns. Neotropical Rochefortia is distributed over most Caribbean islands, Central America and northern South America. Twenty-eight validly published names (corresponding to twenty-one typified taxa at the species level and below) are available in Rochefortia, but the precise number of species to be accepted has been elusive before this revision. New information In the course of the present revision, 353 herbarium collections, comprising approximately 540 Rochefortia specimens, were entried into a BRAHMS data base providing information about protologues and types and retrospective georeferences if possible. Based on the combination of molecular and morphological data we propose to recognise nine species of Rochefortia, namely R. acanthophora, R. bahamensis, R. barloventensis, R. cubensis, R. cuneata, R. lundellii, R. oblongata, R. spinosa and R. stellata (the remaining nineteen validly published names are synonymised under such names). Morphological description of each species and an identification key are provided.

multiple reduced leaves. No intermediate structures between the strobili and mature plant parts such as leaf clusters or inflorescences have been observed in the course of this revision. To the best of our knowledge, they have not been noted before in Rochefortia, and we interpret such structures as galls developed after induction of insects such as mites. Fig. 2). Phyllotaxis in mature parts of the plants is predominantly fasciculate, but is sometimes alternate or rarely subopposite in the big-leaved mainland species (i.e., R. lundellii, R. spinosa) and to some extent also in R. cuneata from Jamaica. The length of the petiole is variable ranging from 0.05-0.2 cm in R. acanthophora and R. cubensis to 0.3-0.5 cm in R. stellata and considerably longer (1.5-2.0 cm) in the species with intermediate sized and large leaves (i.e., R. bahamensis, R. barloventensis, R. cuneata, R. lundellii, R. spinosa).

LEAVES (
Leaf texture is usually coriaceous and occasionally membranaceous (individuals of R. cuneata). The most common leaf shapes in (woody Boraginales such as) Rochefortia are elliptic and obovate, some individuals in R. bahamensis and R. barloventensis additionally have nearly spherical leaves. In general, plants with larger leaves (i.e., >5.0 cm) assigned to R. cuneata, R. lundellii and R. spinosa are rather easily distinguishable from plants with smaller leaves (i.e., <5.0 cm) present in, for example, R. acanthophora and R. bahamensis. Rochefortia cubensis is the species with the smallest leaves (1.0 cm maximal length), while R. lundellii and R. spinosa are at opposite extremes with leaf lengths up to 12.0 cm. The lamina is always simple, with the margin entire or sometimes revolute (e.g., R. cuneata) and with the tips ciliate. The leaf base is cuneate or rounded, while the apex is rounded through retuse, acute or sometimes cuspidate (R. lundellii and also a few individuals of R. spinosa). Leaf indument usually comprises at least few scattered trichomes at midribs, but leaves and individuals being completely glabrous are occasionally found in R. bahamensis, R. barloventensis, R. cuneata, R. lundellii and R. spinosa. The presence of a more extensive indument leading to a, for example, hirsute surface of leaves is likewise rare (e.g., R. cubensis, R. stellata). Trichomes are predominantly unicellular and simple, with the exception of R. stellata having characteristic multi-branched and star-shaped trichomes (Fig. 2). Usually, the trichomes on the abaxial leave surface (sometimes also on the adaxial surface) causing the typical roughness of the leaf surface contain cystoliths (that are present also in adjacent subsidiary cells). Function of such cystoliths remains rather elusive at present and may include either excretion or repellant or defence against herbivores. On a single herbarium specimen (Lasser 758: US!) determined as R. spinosa, two deciduous stipules are noted that are generally rare in Ehretiaceae (Gottschling et al. 2016).

FLOWERS.
Generative organs are rarely documented in herbarium specimens, whereas knowledge about flowers and fruits are particularly scarce for Cuban species of Rochefortia. The basic monotelic architecture being thyrsoid shows little variation in Rochefortia, and inflorescences are positioned both axillarily and terminally. The number of flowers in each inflorescence usually varies between 3-10, but can be increased up to 15 ( R. lundellii, R. spinosa) or can be reduced to a cluster of 2 and sometimes to a single flower (R. acanthophora, R. cubensis). In inflorescences, bracts are absent in Rochefortia, and flowers are pedicellate through subsessile. The latter trait has taxonomic importance to delimit, for example, R. acanthophora (with sessile flowers) from morphologically similar species (such as R. cubensis with shortly pedicellate flowers).
In Rochefortia, flowers are actinomorphic, tetracyclic, pentamerous and unisexual. Most species have small flowers with corolla diameter of about 0.40-0.50 cm, while R. bahamensis has significantly larger flowers up to 0.70 cm in corolla diameter (♂ individuals). The synsepalous calyx is coriaceous and its aestivation imbricate (plesiomorphic condition in Ehretiaceae: Gottschling 2004). The calyx tube is short, and the 5 (or rarely 4 or 6) lobes are obovate or triangular (R. stellata), with an acute apex. The outer surface is hirsute and ciliate at tips, whereas the inner surface is glabrous and sometimes, a few scattered trichomes are present towards the distal part. The sympetalous corolla is membranaceous and its tube funnel-shaped, occasionally 4 or 6 instead of usually 5 lobes are present. Both corolla surfaces are glabrous, somewhat rugose, and slightly ciliate at tips. Corolla colour is usually white or yellow, occasionally whitish green.
Female and male flowers differ only with respect to formation of gynoecium and androecium, but not to perianth. Male flowers have very well developed stamens with (in outline) reniform functional anthers as demonstrated by the presence of pollen (visible with the stereo microscope at 60x magnification). Filaments are flattened, which is another unusual character within Ehretiaceae (Lefor 1968). The ovary in male flowers is conical, choricarpous to symplicate at the base and proceeds apically into two rudimentary stylodia (Irimia and Gottschling 2015). The adaxial surface of the stylodia is strigose. Overall, morphological variation in male flowers is low between species of Rochefortia.
Female flowers have smaller, shrivelled anthers lacking pollen (verified in SEM in the course of the present study) on short filaments. The ovary is globose and exhibits the coenocarpous-syncarpous architecture usually developed in Ehretiaceae (Gottschling 2004, Gottschling et al. 2014a 2  2  6  3  2  7  3  2  -1  3  3   fruit  5  7  7  4  9  12  12  13  9  7  9  6 Flowers are sometimes fragrant (as noted on herbarium specimens) indicating zoophily like in many other Ehretiaceae. There is a single report about pollinators available from herbarium collections (Zanoni et al. 39552: MO!) stating that flowers are visited by numerous bees (species not indicated).

FRUITS.
Fruit is indehiscent and drupaceous, with the shape (sub-)spherical and a diameter of 0.60-0.70 cm. Individuals of R. lundellii from Costa Rica exhibt the largest fruits at all found in Rochefortia with a diameter of 1.00-1.20 cm. The inner architecture of the fruit, and particularly of the endocarp, corresponds (almost indistinguishable) to the four-parted type known from the Ehretia P.Browne I clade (Ehretiaceae; Pitot 1939, Verdcourt 1991, Gottschling and Hilger 2001. The abaxial surface of the pyrenes varies from smooth and plain (R. oblongata) through reticulately ornamented with ridges in most other species such as R. spinosa (Miller 1989). The seed is bent and surrounds extensive placental tissue that is not enclosed in an individual sterile chamber of the pyrene (as it is the case in Bourreria: Gottschling 2004, likewise from Ehretiaceae).

Distribution and habitat
Most Rochefortia species grow in dry, only seasonally wet climate, relatively close to the sea and at low altitudes. Preferred substrates include rocky and alkaline soils with a calcareous layer, and most of the West Indian species are reported to occur on both limestone and serpentine. Species of Rochefortia are important elements of xeromorphic plant communities that are notedly characteristic in Cuba and include large portions of endemics (Borhidi 1991). Somewhat deviating from the other species of Rochefortia, Central American R. lundellii and South American R. spinosa are abundant in wet forests at higher altitudes.
Rochefortia is restricted to Caribbean islands and the adjacent American mainland (Fig. 3  Circumcaribbean distribution of Rochefortia. Note that many species of Rochefortia are delimited geographically and that R. acanthophora, for example, has a more restricted range on the Greater Antilles (i.e., is absent from Cuba and Jamaica) than previously considered. geographic occurrence rather than morphology is indicative for species determination (Irimia et al. 2015).

Materials and methods
Delimitation of Rochefortia species was inconsistent among previous authors (Lefor 1968, Klotz 1980, Klotz 1982 because of a high degree of variability and plasticity of morphological traits. Since then, there are significantly more collections available in the herbaria of the world than were studied before, and this allowed for a comprehensive review of the morphological variability over the entire geographic range of Rochefortia. Our species circumscriptions are based on two major sources of information, namely 1) molecular phylogenetics comprising an exhaustive taxon sample over the entire morphological variation and geographical range of Rochefortia populations (Irimia et al. 2015) and 2) morphological investigations of 353 herbarium collections comprising approximately 540 Rochefortia specimens.
Species of Rochefortia exhibit a clear biogeographic correlation (Fig. 3) as inferred from molecular sequence data (Irimia et al. 2015). The Caribbean group comprising 7 species constitutes the sister group of the two joint mainland species. Within the Caribbean species group, R. barloventensis is largely restricted to the Lesser Antilles (Irimia and Gottschling 2015), whereas R. acanthophora mainly occurs on the eastern Greater Antilles. The remaining 5 species are distributed over The Bahamas, Cuba and Jamaica (but phylogenetic resolution within that clade is poor). This basic scaffold provided by molecular sequence data was used to re-evaluate morphological variation documented in numerous specimens of Rochefortia.
We adopted a rather broad morphological species concept for Rochefortia and concluded that sympatric populations of different species should not be difficult to distinguish and should not include morphological intermediates. Basically, we started our revision by addressing the question how many species can be distinguished on every separate island in the Caribbean as center of diversity. As a result, we now recognise 9 species in Rochefortia having distributions that are more or less contiguous. However, the island species (e.g., R. bahamensis, R. barloventensis, R. cubensis), but also Central American R. lundellii, exhibit some degree of disjunction in their distributions.
Different from many other taxa of woody borages, species of Rochefortia lack exclusive characters with respect to generative organs. Using such traits for diagnostic purposes is further impeded since they are rarely documented on herbarium specimens: Already Lefor (1968) and Klotz (1979) complained about the large amount of sterile among Rochefortia specimens. As a result, intraspecific variability of generative organs is continuously not well worked out for species such as R. cubensis, R. oblongata and R. stellata, which remains a challenging future task. Anyhow, length of pedicles, number of flowers per inflorescence and division and total length of styles show considerable variation and appear partly useful to recognise and delimit species as inferred from generative organs.
Vegetative traits help to distinguish between species that occur sympatrically, but the degree of homoplasy is high when considered over the entire geographic range. Individual specimens of, for example, R. bahamensis and R. barloventensis can be remarkably similar in their morphology, although no similar morphologies are found within the geographic distance of more than 500 km. The only highly distinctive trait among species of Rochefortia is the presence of stellate trichomes on leaf surface and other plant parts, which is diagnostic for the Cuban endemic R. stellata (Lefor 1968, Klotz 1982. Moreover, plants with larger leaves (i.e., >5.0 cm) assigned to R. cuneata, R. lundellii and R. spinosa may be easily distinguishable from plants with smaller leaves (i.e., <5.0 cm) determined as, for example, R. acanthophora, R. bahamensis and R. cubensis.
In this revision, we provide comprehensive nomenclatural data about all names published for species of Rochefortia. They are linked to online resources such as Biodiversity Heritage Library (BHL) and Biodiversity Literature Repository (BLR) for bibliography (i.e., protologues) and JSTOR for high quality images of type specimens (although free access is limited). The present printed revision of Rochefortia is also part of an ongoing online project on the dedicated platform for cyber-taxonomy, namely Botanical Research and Herbarium Management System (BRAHMS). We thus made our BRAHMS data base publicly available, which provides access to the information implemented in hundreds of Rochefortia specimens. Searches by taxon, collector, locality name and map area (Fig. 3) are possible and generate tables that can also be shown in text or excel format. The flexibility of the BRAHMS platform will enable us also to upload more images, individual observations and future studies of Rochefortia in a comprehensible way. We thus aim at an improved biodiversity knowledge about a largely neglected branch of Ehretiaceae.

Distribution
Coastal habitats and scrublands across Caribbean islands between Haiti in the West and Guadeloupe in the East, with high abundance in the Dominican Republic, Puerto Rico and the Virgin Islands (symbol "⨀" in Fig. 3), at low altitudes (sea level up to 300 m), occasionally at higher altitudes of 1200 m (Jiménez 4192: US!). Plant species with similarly restricted distributions on the eastern Greater Antilles are otherwise rare (4 taxa at the generic level listed in Borhidi 1991).

Ecology
Flowering throughout the year (Jan-Dec); fruiting Oct-Mar, May-Aug, but probably contiguously.

Taxon discussion
Traditionally, R. acanthophora has been considered the most widely distributed species of Rochefortia in the Caribbean (Lefor 1968), but the results from a molecular survey rather indicate a restricted geographic range (Irimia et al. 2015). Particularly, R. acanthophora has its westernmost distribution in Haiti, but is absent from Cuba (firstly noted by Klotz 1982 because of leaf shape differences) and Jamaica, where it has been believed to occur in the past. Anyhow, the species is well represented on the islands where it occurs, and is the only small-leaved species documented for Haiti and Dominican Republic, Puerto Rico, British as well as US Virgin Islands and Antigua.
Rochefortia acanthophora is sympatric with only a single other species, namely R. barloventensis, from which it differs in the frequently axillary (versus predominantly terminal) inflorescences comprising few (and not more than 5) flowers, a smaller leaf blade size (0.5-1.5 cm long versus 1.4-3.4 cm long) and a reduced leaf petiole length (0.05-0.2 cm long versus 0.4-1.5 cm long). Anyhow, sympatry between both species is restricted to Guadeloupe (Howard 1989) and Puerto Rico (Irimia et al. 2015).
Morphologically, R. acanthophora is a variable species, particularly with respect to leaf size and shape, and exhibits some overlap to R. cubensis from Cuba and Jamaica (it was occasionally hard to determine the species reliably if geographic origin was unknown

Distribution
Across multiple islands of The Bahamas archipelago (Crooked Island, Great Exuma, Inagua, Long Island, Mayaguana, San Salvador) and putatively also in western Cuba (Pinar del Río, Havana) in scrub lands, rocky coppice hills and thicket edges, at sea level or slightly above (symbol "▲" in Fig. 3).

Taxon discussion
Rochefortia bahamensis is an abundant and morphologically very consistent species in The Bahamas archipelago characterised by the predominantly circular leaf shapes. Overall similarity, however, is great with R. barloventensis from the Lesser Antilles, but molecular data indicate that the two species are only distantly related (Irimia et al. 2015). The geographical disjunction (> 500 km apart) provides further evidence for the distinctiveness of both species.
The 3 sterile collections from Cuba are tentatively placed under R. bahamensis and are morphologically somewhat intermediate between R. bahamensis and R. cubensis. With R. bahamensis, the plants share the more membranaceous leaf texture, longer and slenderer petioles, orbicular immature leaves and fewer (maximal 4) leaves clustering in a fascicle. However, they exhibit the dichotomously branched thorn pattern of R. cubensis, and overall leaf size is smaller when compared to the more typical R. bahamensis. Anyhow, molecular data of Hilger & Urquiola 99/20 (B!) indicate that this specimen is distinct from (morphologically also similar, but geographically distant) R. acanthophora and R. cuneata (Irimia et al. 2015).

Distribution
Restricted to islands of the Lesser Antilles (Guadeloupe, Marie Galante, Montserrat, Martinique) and eastern Puerto Rico (symbol "•" in Fig. 3), in arid coastal forests, on wooded hillsides and mesophyll forests at low altitudes (sea level up to 125 m).

Taxon discussion
Rochefortia barloventensis was discovered as a species new to science in the course of the present revision of Rochefortia (Irimia and Gottschling 2015). With respect to leaf shapes and sizes, it is a morphologically variable species and is intermediate between R. bahamensis and R. cuneata exhibiting mature leaves size greater than 3.5 cm (and up to 6.0 cm) long in some specimens from Guadeloupe, Martinique and Puerto Rico. Molecular data indicate the distinctiveness of this new species, whose closest relative is R. acanthophora from adjacent Puerto Rico and the Dominican Republic. The two species can be reliably distinguished based on inflorescence morphology (manyversus few-flowered) and leaf shape (frequently circular versus predominantly obovate). Overall similarity, however, is great with R. bahamensis from The Bahamas archipelago and also with R. cuneata from Jamaica, but molecular data indicate that these species are not closely related (Irimia et al. 2015). The geographical disjunctions provides further evidence for the distinctiveness of all such species. A collection from eastern Puerto Rico has leaves similar in size of R. cuneata or even larger (i.e., 3.5-5.0 cm), but molecular data indicate the correct determination as R. barloventensis (Irimia et al. 2015), though morphologically unusual. Common names: "bois vert" in Martinique (noted on Jussieu s.n.: P!), "espino" in Puerto Rico (Liogier de Sereys Allut and Martorell 1999).

Distribution
Cuba and Jamaica (symbol "+" in Fig. 3), on limestone soils and serpentine, in coastal tickets and dry forests at relatively low altitudes (0-600 m). Plants with similarly restricted distributions are otherwise rare (Borhidi 1991 lists 10 taxa at the generic level, each with only a few species).

Taxon discussion
Rochefortia cubensis is a widely distributed and frequently encountered species in Cuba and Jamaica. It is morphologically similar to, but with respect to molecular sequence data distinct from, R. acanthophora occurring on eastward Caribbean islands (Irimia et al. 2015). In Cuba, leaves are distinctly smaller in R. cubensis than in R. acanthophora, but individuals from Jamaica (e.g., Howard & Proctor 15091: A!, March 462: P!) have leaf sizes in the range of R. acanthophora and are therefore hard to distinguish based on morphology. In Cuba, R. cubensis occurs sympatrically with three other species, namely R. bahamensis (Pinar del Río) and R. oblongata and R. stellata (eastern Cuba). They can be easily distinguished from R. cubensis either because of bigger leaf size (R. bahamensis, R. oblongata) or the presence of multi-branched trichomes (R. stellata). In Jamaica, R. cubensis is sympatric with R. cuneata only, from which it differs in leaf size and texture (coriaceous versus membranaceous) and inflorescence (sessile versus longly pedicellate).
With respect to leaf size and shape, Klotz (1982) payed too much attention to interspecific variation within a possible complex of species. He expressed his concept by the description of R. oblanceata G.Klotz, geographically restricted to Pinar del Río and distinguished from R. cubensis by smaller leaves and narrower shapes. Another population with leaves in this range is found in eastern Cuba (Guantánamo) that Klotz considered likewise a distinct species to be described using the epithet <urbaniana>. Having investigated the species over its full distribution, we think that such leaf morphologies are in the intraspecific range of R. cubensis without clear correlations to biogeography. Future population genetics studies are necessary to evaluate the specific status of multiple populations of R. cubensis and possible morphological correlations. Common names: "bronce", "carbonero", "espuela de caballero" (Span. knight's spur), sargento (Castell Puchades et al. 2013) in Cuba, "green (heart) ebony" in Jamaica. Sw., Prod. 54. 1788, Fl. Ind. occid. 552-553. 1797

Taxon discussion
Across Caribbean islands, R. cuneata exhibits amongst the largest leaves that have almost comparable size to those of the mainland species R. lundellii and R. spinosa. The species is most abundant in Jamaica, from where it was also discovered in the late 18 century. Three collections outside Jamaica (one from Dominican Republic and two th from Haiti) are morphologically similar to R. cuneata, but all attempts failed to verify the determination by DNA sequence data (Irimia et al. 2015).
Olof P. Swartz' names were not properly typified before the present revision (Johnston 1949: 128 indicated that the type originates from Jamaica). There are multiple of his gatherings present in different herbaria, but only UPS holds specimens assigned to both names R. cuneata and R. ovata (and O.P. Swartz was active in Uppsala). We designate explicitely such as type material here, because it is most likely that O.P. Swartz saw it and used it for his descriptions. Whether more material of R. cuneata (S-R-5496!) and R. ovata ( B-W5461! C1-8769! LINN-HS471-2! M-196671! SBT12927!) can be considered original material remains conjecture. Lefor (1968) considered the Willdenow specimen as holotype of R. ovata, but his rationale is elusive (and has no taxonomic relevance as his thesis is not effectively published: ICN Art. 30.8.). Swartz (1788) and Swartz (1797) distinguished his two Jamaican species based on differing leaf shapes (i.e., cuneate versus ovate), but we consider that they are in the morphological range of a single species. Common names: "green ebony" and "bois vert" in Jamaica.

Distribution
Abundant in Mexico, but also present in adjacent and other countries in Central America (Belize, Costa Rica, Guatemala, Nicaragua), as well as western Cuba (symbol "⬡" in Fig. 3), in perennial and deciduous forests on acidic and calcareous soils from low altitudes up to 1400 m. Borhidi (1991) considers the species (as R. spinosa) characteristic for the Bombacopsi cubensi-Thrinacetalia morrisii plant community at the order level occurring in western Cuba.

Taxon discussion
The species has a lianescent habit, which is unusual for Rochefortia and for Ehretiaceae as well, and larger stems may bear truly thick and extensive thorns. However, herbarium specimens of R. lundellii are morphologically difficult to distinguish from South American R. spinosa when growth form is not recorded on the label. Consequently, determination has been more or less arbitrary across both species in the past. Molecular data confirm the distinctiveness between both species (Irimia et al. 2015), but acquisition of sequence data for morphological somewhat divergent (e.g., Costa Rican) population remains a future research task.
Rochefortia lundellii is a variable species across its different geographical occurrences, particularly regarding size of leaves and thorns, shape of leaf blades and the apex, but also fruit diameter. Specifically, the Mexican population exhibits the largest mature leaves 6.4-11.0(-13.0) cm long, followed shortly by the Costa Rican population 6.2-10.0(-12.5) cm and the Cuban population 4.8-9.0(-11.0) cm. Other slight differences are observed in thorn size, ranging from 0.7-1.5 cm long in Mexican plants over 0.5-1.0 cm long in Costa Rican plants to 0.3-0.7 cm long in Cuban plants. Some Costa Rican specimens consistently have robust thorns that are slightly curved at tips (the trait is shared with some individuals from Mexico, but also from Venezuela assigned to R. spinosa). Leaf apex is usually rounded or emarginated in R. lundellii, but some specimens from Costa Rica and Mexico display a cuspidate apex. Fruit diameter ranges within the general Rochefortia average values except for Costa Rican specimens having the biggest fruits (1.00-1.20 cm diameter) of all species.
Still in the 60ies of the past century, Lefor (1968) considered R. lundellii a rarely collected species with a very restricted geographic range. The species name was even ignored by Sauget y Barbis [Léon] and Liogier de Sereys Allut [Alain] (1957) and Klotz (1982), and they filed Cuban specimens under R. spinosa with reference to South America. It is impressive to see how collection efforts by herbaria such as MEXU and MO have the potential to completely revise our view on plant species and their distributions. Today, R. lundellii is one of the best known species of Rochefortia and well documented over a wide geographic range in multiple herbaria.

Distribution
Endemic to eastern Cuba (symbol "⌾" in Fig. 3), in tidewater flats and dry bushes at 0-300 m altitude.

Ecology
Fruiting Jun.

Taxon discussion
The species is very similar to Jamaican R. cuneata, but differs in having (at least some) thorns branched and also in leaf traits exhibiting numerous cystoliths and peculiar roughness at touch. Rochefortia oblongata is sympatric with R. cubensis and R. stellata, from which it can reliably be distinguished based on leaves and petioles that are both much longer than in the other species. Moreover, the abaxial surface of pyrenes is entirely smooth (versus reticulate in R. cuneata and all other species of Rochefortia).

Distribution
Northern South America (symbol "□" in Fig. 3) in deciduous costal dry forests, in medium and high moist forests, on dry steep cliffs and limestone soils at altitudes between 0-1300 m.

Taxon discussion
Rochefortia spinosa is among the species with the largest leaf size after R. lundellii. Specimens across different geographical areas are relatively homogenous displaying a low variability of morphological traits (e.g., few collections have leave lengths shorter than 5.5 cm). The species is not sympatric with any other species but morphologically, it resembles R. lundellii. It can be distinguished from the latter by the presence of 2 stylodia and generally by the less extensive developed thorns on stems. In the past, R. spinosa was one of the most confusing Rochefortia species and was believed being distributed across multiple islands of the Caribbean. However, molecular data (Irimia et al. 2015) indicate that the species is restricted to northern South America (primarily Colombia and Venezuela, but also Peru though with few collections available).

Distribution
Rochefortia stellata (symbol "•" in Fig. 3) is endemic to the southern and eastern provinces of Cuba (i.e., Granma, Guantánamo, Holguín, Santiago de Cuba; Borhidi 1991) and occurs in coastal forests and tickets on limestone and serpentine soils as well, between 10-600 m altitude, sympatrically with R. cubensis and R. oblongata.

Taxon discussion
Rochefortia stellata is the most distinctive species and can be easily distinguished from all other Rochefortia species, because of the consistent presence of multi-branched (i.e., stellate) trichomes (Fig. 2) on young twigs, petioles and leaves (on abaxial surface, stellate trichomes are much more abundant and persistent over time, whereas those on the adaxial surface can be lost at maturity). Together with the restricted distribution in eastern Cuba, the species can therefore be reliably identified, even in vegetative stage. Many individuals exhibit branched thorns, which is shared with R. cubensis and R. oblongata only.
Within his Rochefortia sect. Stellatae, Klotz (1980) distinguished a number of taxa at the species level and below, because he observed morphological variation in correlation with geographic occurrence. Specimens with the smallest leave size and narrowest blade (0.8-1.2 cm long, 0.2-0.3 cm wide) occur mainly in Holguín: Sierra de Nipe (being type localities of R. septentrionalis and R. septentrionalis var. obovata) and Sierra Cristal (type locality of R. septentrionalis var. cristalensis), but are also found elsewhere. Plants with scattered stellate trichomes on the upper surface are not confined to Baitiquiri (type locality of R. victoriniana), but can be also observed in other Cuban provinces. Generally, density and occurrence of stellate trichomes rather