Summary1. The effects of the present biodiversity crisis have been largely focused on the loss of species. However, a missed component of biodiversity loss that often accompanies or even precedes species disappearance is the extinction of ecological interactions. 2. Here, we propose a novel model that (i) relates the diversity of both species and interactions along a gradient of environmental deterioration and (ii) explores how the rate of loss of ecological functions, and consequently of ecosystem services, can be accelerated or restrained depending on how the rate of species loss covaries with the rate of interactions loss. 3. We find that the loss of species and interactions are decoupled, such that ecological interactions are often lost at a higher rate. This implies that the loss of ecological interactions may occur well before species disappearance, affecting species functionality and ecosystems services at a faster rate than species extinctions. We provide a number of empirical case studies illustrating these points. 4. Our approach emphasizes the importance of focusing on species interactions as the major biodiversity component from which the 'health' of ecosystems depends.

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Jacquemontia reclinata House (Convolvulaceae) is a federally listed endangered species endemic to coastal strand habitat of south-eastern Florida. In order to identify the closest relatives of J. reclinata, a phylogenetic reconstruction was performed based on nucleotide sequence data from the internal transcribed spacer region of nuclear ribosomal DNA and from the trnH-psbA intergenic spacer of chloroplast DNA. The three putative relatives of J. reclinata and the majority of Jacquemontia Choicy species known to occur in the Caribbean Islands were included. The strict consensus tree concurs with previous morphological studies, indicating that J. reclinata is closely related to the Caribbean species J. cayensis Britton, J. curtisii Hallier f., and J. havanensis (Jacq.) Urb. These three species and J. reclinata form an unresolved clade. Nucleotide divergence within this clade is low, suggesting that the group is recent, perhaps diversifying after the latest glacial period. These taxa need to be studied further using population-level DNA markers. Most species endemic to the Caribbean Basin form a strongly supported clade. Our phylogeny supports Convolvulus nodiflorus Desr. as part of Jacquemontia. In addition, J. ovalifolia (West) Hallier f. ssp. sandwicensis (A. Gray) K.R. Robertson is sister to the Antillean endemic J. solanifolia (L.) Hallier f.

Ipomoea microdactyla Griseb. (Convolvulaceae) is restricted to the Bahamian archipelago, Cuba, and southeastern Florida. The species is listed as a state endangered species in Florida, where it is mostly restricted to the hyperfragmented pine rockland of Miami‐Dade County. Using seven DNA microsatellite loci, we assessed levels of genetic diversity for 12 populations of this species from Andros Island in the Bahamas (six sites), Cuba (one site), and Florida (five sites). We found significantly greater mean numbers of alleles, and higher mean values for both observed and expected heterozygosity in populations from the continuous forest on Andros than those from the habitat fragments in Florida. It is unknown if these patterns of genetic diversity in the Florida populations are the result of habitat fragmentation or founder effects. The population from Cuba exhibited relatively high levels of genetic variation, suggesting that this island is a major center of diversity and dispersal for this species. It appears that hybrid introgression for I. carolina alleles within I. microdactyla individuals occurred at a single site on Andros Island. Overall, the mean inbreeding coefficient value was 0.089, suggesting low levels of inbreeding. The highest inbreeding coefficient values were mostly recorded in Florida. Two groups were revealed, one containing the populations from Florida, and the second one encompassing those from the Bahamas and Cuba. Our results highlight the negative genetic consequences of habitat fragmentation and support initiatives recently established to establish corridors to connect the remnants of the pine forest of the Miami‐Dade County.

Oviedo, R., Traveset, A., Valido, A. & Brull, G. 2009. On the presence of Cneorum (Cneoraceae) in Cuba: an example of biogeographic disjunction between the Mediterranean and the Caribbean? Anales Jard. Bot. Madrid 66(1): 25-33 (in Spanish).The main goal of the study was to shed light on the enigmatic world distribution of the Cneoraceae family, frequently, and until very recently, used as an example of the connection between the Mediterranean and the Caribbean floras. Specifically, we wanted to document the presence/absence of an endemic taxon, first collected in 1861 by Charles Wright from Cuba (Cneorum trimerum). During the last five years, we have visited all the localities where this taxon was originally collected, at Sierra Maestra in eastern Cuba, and revised all available herbarium material. Moreover, we checked all botanical and historical references, and also interviewed local people, to whom we showed pictures of the Mediterranean Cneorum. The conclusions of our survey are the following: i) nowadays, there are no Cneorum plants growing in their type localities in Cuba; ii) all the collected material from Cuba and deposited in herbaria by Wright, and also others studied by Carlquist, correspond unequivocally to C. tricoccon. The material collected by Ekman in 1922, and identified as C. trimerum, is sterile, and cannot be identified with certainty, however we think it is unlikely to be C. tricoccon; iii) this plant was probably introduced during the mid 19 th century from Southern France, although it never become naturalized. The presence of French colonist settlements in coffee plantations in those areas where Cneorum was collected, together with the fact that the plant has medicinal properties, lead us to suggest that the colonist themselves were those introducing the plant in Cuba. Lastly, iv) Schoepfia stenophylla (Olacaceae) has also been recently misidentified as Cneorum tricoccon due to the resemblance of their leaves. Schoepfia stenophylla is an endemic El objetivo del presente estudio es esclarecer la, hasta ahora, enigmática distribución mundial de la familia Cneoraceae y confirmar la existencia de un posible taxon de esta familia en Cuba, el cual es frecuentemente usado como ejemplo de conexión entre la floras del Mediterráneo y el Caribe. Para ello, durante los últimos cinco años, se han realizado intensas prospecciones de campo en aquellas áreas donde previamente se había documentado la presencia de una especie de Cneorum (identificada inicialmente como C. trimerum y como C. tricoccon posteriormente) en Sierra Maestra, Cuba. Además, se ha revisado material de herbario y bibliografía diversa. La presencia de antiguos asentamientos de cafeteros franceses en las localidades donde se colectó esta especie, junto con el hecho de presentar propiedades medicinales (en hojas y frutos), hace posible que fuera introducida intencionadamente en Cuba desde el sur de Francia por los propios colonos a mediados del siglo XIX. Concluimos que esta especie no se encuentra ya en Cuba, y creemos que nunca...