RESUMO
Although drosophilids have been extensively studied in laboratories worldwide, their ecology is still relatively poorly understood. This is unfortunate because some species are currently expanding their geographic distribution and infesting fruit crops. Here, we investigated the relationship between drosophilids and potential plant hosts in a commercial fruit and vegetable distribution center in the Neotropical region. We collected discarded fruits and vegetables from this commercial center during two time periods (2007-2008 and 2017-2018). Resources were weighted and individually monitored in the laboratory. The drosophilids that emerged were identified, and the relationship between them and their resources was explored. From the 99,478 kg of potential hosts collected, we identified 48 plant taxa, from which 48,894 drosophilids of 16 species emerged. On both collecting occasions, drosophilid assemblages were strongly dominated by basically the same exotic species, which explore a broader range of resources, especially those of exotic origin, when compared to neotropical drosophilids. These results are concerning because the studied site, Along with other urban markets around the world, might be acting as sources of generalist widespread species that disperse to surrounding natural vegetation and contribute to biotic homogenization.
RESUMO
BACKGROUND AND AIMS: Psidium is the fourthth largest genus of Myrtaceae in the Neotropics. Psidium guajava is widely cultivated in the tropics for its edible fruit. It is commercially under threat due to the disease guava decline. Psidium cattleyanum is one of the 100 most invasive organisms in the world. Knowledge of the phylogenetic relationships within Psidium is poor. We aim to provide a review of the biology, morphology and ecology of Psidium, a phylogenetic tree, an infrageneric classification and a list of species. METHODS: Morphological and geographic data were obtained by studying Psidium in herbaria and in the field between 1988 and 2020. Forty-six herbaria were visited personally. A database of approx. 6000 specimens was constructed, and the literature was reviewed. Thirty species (about a third of the species in the genus) were sampled for molecular phylogenetic inference. Two chloroplast (psbA-trnH and ndhF) and two nuclear (external transcribed spacer and internal transcribed spacer) regions were targeted. Phylogenetic trees were constructed using maximum likelihood (ML; RaxML) and Bayesian inference (BI; MrBayes). KEY RESULTS: Psidium is a monophyletic genus with four major clades recognized as sections. Section Psidium (ten species), to which P. guajava belongs, is sister to the rest of the genus; it is widespread across the Neotropics. Section Obversifolia (six species; restricted to the Brazilian Atlantic Forest), which includes P. cattleyanum, is sister to the innermost clade composed of sister sections Apertiflora (31 species; widespread but most diverse in the Brazilian Atlantic Forest)â +â Mitranthes (26 species; widespread in dry forests and probably diverse in the Caribbean). Characters associated with diversification within Psidium are discussed. CONCLUSIONS: Research on pre-foliation, colleters, leaf anatomy, leaf physiology, staminal development, placentation and germination associated with the anatomy of the opercular plug is desirable. Studies are biased towards sections Psidium and Obversifolia, with other sections poorly known.
Assuntos
Myrtaceae , Psidium , Teorema de Bayes , Florestas , Myrtaceae/anatomia & histologia , Myrtaceae/genética , Filogenia , Psidium/genéticaRESUMO
The state of Sergipe has suffered extreme reduction of its Atlantic Forest area in the last decades. The objective of this study is to present an inventory of the Mata do Crasto flora, the largest Atlantic Forest Remnant in Sergipe (approximately 1,000 ha), located in the Municipality of Santa Luzia do Itanhy. An intensive survey was undertaken with monthly plant collections in the study area, for four years (1995 to 1999). Additionally, collections deposited in herbaria were consulted to complete the species list. A total of 324 species were found, belonging to 84 families and 193 genera. This study adds an additional 29 genera and 96 species to the Sergipe flora as new occurrences. The four most speciose families were the Fabaceae (33 species), Rubiaceae (24 species), Myrtaceae (23 species) and Melastomataceae (15 species), that accounted for ca. 30% of the total species. The taxonomic distinction of the area is very similar to three other lowland forests in Northeastern Brazil, although its species composition is quite distinct.
O estado de Sergipe sofreu extrema redução da área de Mata Atlântica nas últimas décadas. Este trabalho tem como objetivo inventariar a composição florística da Mata do Crasto, maior remanescente de Mata Atlântica de Sergipe (aproximadamente 1.000 ha), situada no Município de Santa Luzia do Itanhy. Um inventário intensivo foi realizado com coletas florísticas na área de estudo por quatro anos (1995 a 1999). Adicionalmente, exsicatas depositadas em herbários foram consultadas para complementar a lista de espécies. Um total de 324 espécies foram identificadas, pertencentes a 84 famílias e 193 gêneros. Este estudo adicionou 96 espécies è flora de Sergipe como novas ocorrências. As famílias com maior número de espécies são Fabaceae (33 espécies), Rubiaceae (24 espécies), Myrtaceae (23 espécies) e Melastomataceae (15 espécies), que juntas somam cerca de 30% do total de espécies. A distinção taxonômica do remanescente é surpreendentemente similar ao de outras florestas de terras baixas no Nordeste do Brasil embora suas espécies sejam bastante distintas.
RESUMO
The genus Peristethium, characterized by determinate inflorescences protected by deciduous bracts, occurs in the northwest of South America, as well as Costa Rica and Panama. The main objective of this paper was to transfer one species to what we believe is its correct generic placement in Peristethium, that likewise implies in a shift of the genus' distribution beyond the Amazon. A new combination, Peristethium reticulatum, is proposed, based on Struthanthus reticulatus, described from Tocantins in 1980. The sexual dimorphism of the inflorescences of P. reticulatum (sessile male flowers and pedicellate female flowers) associated with male inflorescences that are inserted at leafless nodes are unique within the genus. The male flowers have dimorphic stamens, well-developed anthers and a pistiloid, whilst female flowers have robust styles and stigmas, and much reduced staminodes. Peristethium reticulatum and P. polystachyum occurs in the Amazon regions of Brazil, with the former recorded also in the ecotone with the Central Brazilian savannas (Cerrados).
O gênero Peristethium, caracterizado por inflorescências determinadas protegidas por brácteas decíduas, ocorre no noroeste da América do Sul, além da Costa Rica e Panamá. O objetivo do presente trabalho foi transferir uma espécie para o que acredita-se ser seu correto posicionamento genérico em Peristethium, o que também implica em concomitante alteração da distribuição geográfica deste gênero para além da Amazônia. A nova combinação, Peristethium reticulatum, é proposta, baseada em Struthanthus reticulatus, descrita para o Tocantins em 1980. O acentuado dimorfismo sexual das inflorescências de P. reticulatum (flores masculinas sésseis e as femininas pediceladas), juntamente com a origem de inflorescências masculinas em nós áfilos são únicos dentro do gênero. As flores masculinas apresentam estames dimorfos, anteras desenvolvidas e pistilódio, enquanto as flores femininas possuem estiletes e estigmas robustos e estaminódio reduzido. Peristethium reticulatum e P. polystachyum ocorrem em regiões amazônicas do Brasil, sendo a primeira registrada também em ecótono com o Cerrado.
