Biology subjects

Simoes, A. R. G.

Publications and source records attributed to Simoes, A. R. G..

4 recordsLinked to original sources

bioRxiv2024

Too hot for the weeds? Exploring the impact of climate change in herbaceous Convolvulaceae in Cerrado and Mata Atlantica biomes (SE Brazil)

AimWe investigated the potential resilience to climatic change of nine species of weeds in Convolvulaceae, using predictive spatial modeling across two contrasting biomes in Southeastern Brazil: Cerrado (=Savanna) and Mata Atlantica (=Atlantic Forest). We inferred future changes in distribution area, the climatic variables that will be most impactful, and the potential occurrence of future climatic refuges. LocationSoutheastern Brazil (Sao Paulo, Brazil). MethodsA total of 195, taxonomically vetted, distribution records were compiled for nine species of Convolvulaceae. Potential distribution areas were modelled in RStudio 1.3.1056 with R 3.6.3 using modleR; environmental layers used were the 19 bioclimatic variables with 30 seconds resolution. After a correlation analysis, four bioclimatic variables were selected for distribution modelling: Temperature Seasonality (BIO4), Mean Temperature of Wettest Quarter (BIO8), Precipitation of Wettest Month (BIO13) and Precipitation of Driest Quarter (BIO17). The species distribution modelling was performed using the Maxent algorithm for the present time (1960-1990) and for future projections (2050 and 2070), under two different scenarios of projections, moderate and pessimistic.. The final distribution models were generated through the selection of primary models with a minimum level of TSS (True Skills Statistics) equal to 0.7. ResultsThe analysed species demonstrated different levels of response to climatic change: Distimake aegyptius, D. dissectus, and Evolvulus pteurocaulon exhibited a gain in the climatic suitability range, regardless of the future scenarios. Other species, such as E. glomeratus, Ipomoea bonariensis, and I. alba showed a decline in climatic suitability range, more accentuated in the pessimistic scenario. Three species showed a positive response in a moderate future scenario, but a decline in the most extreme projection. Areas that may act, in the future, as climatic refuges for the displaced species are also highlighted, in view of being prioritised for conservation. Main ConclusionThis study reveals that climate change will have varied impacts on herbaceous species of Convolvulaceae occurring in the Brazilian Cerrado and Mata Atlantica biomes. Some species are likely to benefit from climate change, showing an increase in climatic suitability in both moderate and pessimistic future scenarios. Other species, however, are expected to experience a decline in suitable climatic conditions, in particular under the most pessimistic climatic scenario, and are more likely to be threatened in the future, due to the constriction of suitable habitats. The analysis also highlights that certain regions may serve as important climatic refuges for these species in the future. These findings emphasize the necessity for targeted conservation plans to protect the biodiversity of the Cerrado and Mata Atlantica phytogeographic domains and weed management strategies - not only in the present but also in future climatic conditions.

ecology↗

bioRxiv2024

Convolvulaceae of Guinea: taxonomy, conservation and useful plants

Convolvulaceae is a diverse and economically important plant family in Tropical Africa, including the crop sweet potato (Ipomoea batatas (L.) Lam.) and its wild relatives, morning glories (Ipomoea L.), bindweeds (Convolvulus L.), invasive weeds (e.g. Cuscuta L.) and several other species with food, medicinal, or traditional uses. A taxonomic treatment of Convolvulaceae for Guinea is here presented, including comprehensive morphological descriptions, identification keys to genera and species, distribution and ecological information, specimen data, and documentation of known uses. A total of 51 species belonging to 16 genera are documented, 38 of which are native, and 13 presumed introduced; 33 of these are used as medicine, 18 as ornamental, 12 as food and 15 with a range of other uses. Preliminary IUCN Red List assessments were carried out for 45 species for which there were no previous assessments All 45 preliminary conservation assessments were categorised as Least Concern for the global Red List, with 61% of native species having at least one occurrence point falling within protected areas.

plant biology↗

bioRxiv2024

Advancing knowledge of West African morning glories: a taxonomic revision of Ipomoea L. (Convolvulaceae) from Ghana

Ghanas plant diversity is estimated at 2,974 plant species, belonging to 1,077 genera and 173 plant families. However, a Flora of Ghana is yet inexistent: targeted floristic and taxonomic studies are still much needed to document the plant diversity of the country fully at the family, generic and species levels. This is essential for identifying priority conservation areas in the country and support further research in crop wild relatives or medicinal plants, which will help tackle food insecurity and improve livelihoods. In this study, we provide a taxonomic revision of the Ipomoea spp. in Ghana to enhance their identification, conservation and sustainable utilization as food and medicine among other uses. An extensive literature review was carried out, including historical references and online taxonomic databases, to recover information on accepted names, type specimens and synonyms, followed by consultation of herbarium specimens at GC herbaria, to retrieve morphological information and database specimens. Specimen locality information was georeferenced, and records plotted onto distribution maps. As a result, this work provides an identification key to the species of Ipomoea of Ghana, nomenclatural information, comprehensive morphological descriptions, detailed list of examined specimens, distribution maps and notes on conservation status and traditional plant uses. In total, 28 species are fully described, 20 of which are native and eight introduced from the Americas; five are new records to Ghana.

plant biology↗

bioRxiv2023

New to Ehretiaceae: Keraunea. Re-evaluation of a genus of climbers from Brazil.

We definitively place Keraunea, a genus of showy forest climbers from remnants of the Mata Atlantica of Brazil, in Ehretiaceae. Previously Keraunea had been ascribed to Convolvulaceae based on morphology, or divided between Malpighiaceae and Ehretiaceae based on molecular analyses (polyphyletic). Keraunea is morphologically anomalous in the Ehretiaceae, having fruits which are held in the centre of a large wing-like bract by adnation of the pedicel, and due the stem-twining habit of some species. However, morphologically Keraunea shares two apomorphies with monotypic Cortesia Cav., halophytic shrubs of Argentina: 1) "two parted endocarps" (the fruit contains two endocarps each with two 1-seeded cells, while four 1-seeded endocarps are plesiomorphic in Ehretiaceae) and 2) a large bract that subtends the flower (absence of bracts is plesiomorphic in Ehretiaceae). A combined tree using four markers (ITS, trnL-F, rbcL and matK) places the three species of Keraunea sampled unambiguously in a clade with Ehretia + Cortesia + Halgania and monophyly for Keraunea is shown with high support. In an ITS tree Keraunea is sister to Cortesia with low support. We expand the generic description of Keraunea including the first account of the internal fruit structures and the seed, and present new data on the vegetative architecture including variation within the genus, some species being stem twiners while one species at least, is described as a scandent shrub. Keraunea lombardiana, previously included within K. brasiliensis, is formally described from Minas Gerais and Bahia as the third species of the genus and both these species are described. In all five species are recognised but two, known to us only from digital images, are not formally described because sufficiently detailed descriptions cannot be made. All five species are mapped, and provisional conservation assessments are recorded, of either Endangered or Critically Endangered. The state of Bahia, with three species, has the highest species diversity, mainly in dry forest. Three species appear confined to moist coastal forest, extending southwards from Bahia to the state of Rio de Janeiro. Keraunea remains incompletely known. Not one of the species has both anthetic flowers and fruits described. Studies on pollen, germination, anatomy, embryology and phytochemisty are entirely lacking. Field observations of pollination, seed dispersal and phenology are also required. However, the most urgent requirement is undoubtedly a formal taxonomic revision based on a full herbarium search and targeted fieldwork, with full IUCN 2012 extinction risk assessments for each taxon. This is urgent because it seems that all the taxa that we present in this paper (and more that can be expected to be found) appear to be highly range restricted and generally not to occur in protected areas, and so appear to be highly threatened.

plant biology↗