Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

This article explores the historical significance of urban informality, understood both as a mode of urbanization and as a key element in broader histories of racial inequality, governance and social struggle. It analyzes the relationship between urban informality and three important historical threads: the evolution of racialized governance, the tense coexistence of private and public power, and the contradictory interweaving of social struggle and inequality. Keywords: favela; urban history; racial inequality; informality.

Background and Aims: The flora of the dry forest of Cerros del Tabacal and the semi-deciduous forest of Loma del Agua of the Reserva Forestal Guanito in the Cordillera Central of the Dominican Republic, is presented. There are few species records of this reserve. Hence, the main objective was to inventory the vascular flora of both hills, and the specific objectives, to determine the diversity and richness of species in the Reserva Forestal Guanito and to document the biogeographic, conservation status, and life forms, and to register the floristic composition variation. Methods: Three plots of 10 × 10 m and two transects of 60 × 2 m were made on each hill, based on the species expression minimum area, and they were located in the areas with dense plant cover. The Shannon diversity index, Berger-Parker dominance index and Jaccard similarity coefficient were calculated. Key results: In the dry forest 81 species were recorded, distributed in 72 genera and 31 families; in the semi-deciduous forest, 110 species belonging to 96 genera and 50 families were registered. Fabaceae was the richest family in genera number on both hills (eight and nine, respectively), and Tillandsia the richest genus in species number (six and five, respectively). Tillandsia recurvata stands out with the highest abundance of individuals (173 individuals) in the dry forest, and Savia sessiliflora (39) in the semi-deciduous forest. The Shannon index showed that the semi-deciduous forest has more diversity than the dry forest, and the results of the Jaccard coefficient indicated that both hills have a highly differentiated floristic composition. Conclusions: This study reaffirms the importance and floristic richness of the forests of the Domincan Republic and at the same time constitutes the first floristic inventory for the Reserva Forestal Guanito.

Background and Aims: The Libellus de Medicinalibus Indorum Herbis (Little Book of the Medicinal Herbs of the Indians) includes 185 beautifully illustrated plants, 131 interpreted to species. Only some have been investigated regarding their attributed properties. Therefore, we selected six plants used as anti-inflammatories. The objectives of this work were to corroborate their botanical identity and to determine if contemporary chemical and pharmacological information supports their ancient therapeutic applications.Methods: The illustrations of the chosen plants were compared with specimens from the MEXU Herbarium to propose their possible taxonomic identity. The phytochemistry and anti-inflammatory activity of these species were reviewed in databases.Key results: The six plants selected from the Codex correspond to five species, since we consider that tetzmitl (Folium 13r) and texiyotl (Folium 22v) plants are the same species: Sedum dendroideum. Extracts from the leaves of S. dendroideum have shown anti-inflammatory activity in different pharmacological models due to derivatives of the flavonoid kaempferol, which supports its ancient medical applications to treat swollen face, eyes, and mouth. In Folium 48v, tzihuac copalli and tlacoecapatli are prescribed when “the vein punctured by the phlebotomy swells.” We agree they are Bursera bipinnata and Litsea glaucescens, respectively. To date, their possible anti-inflammatory properties have not been investigated, but other related species do present these. The Folium 22v recommends tememetla and tequixquiçacatl to relieve inflamed mouth. We corroborate that they are Echeveria gibbiflora and Distichlis spicata, respectively. These species do not have chemical-pharmacological studies.Conclusions: The bibliographic review suggests that anti-inflammatory properties attributed to S. dendroideum in the Codex have chemical and pharmacological support. Chemotaxonomic and pharmacological information suggests that B. bipinnata and L. glaucescens could bear these attributes and should be investigated experimentally. These three species are still used as anti-inflammatory in contemporary traditional medicine.

Background and Aims: Gonolobus comprises around 150 species in the world, with just over 40 of them distributed in Mexico. In the last two years, at least five new species have been described for this country. This paper describes a new species within the subgenus Pseudolachnostoma.Methods: Thirteen herbaria, three digital databases, and specialized literature were revised. Based on this, similar species were compared, and an identification key was generated. Field expeditions were made from 2019 to 2022 to gather botanical collections and monitor the phenology of the species of interest. The cohesive species concept was proposed as an explanatory hypothesis for the recognition of the taxa discussed here. Key results: The new species, Gonolobus gonzaleriarum, is described and located in two forests of Pinus-Quercus between the southeastern and southwestern limits of the states of Sinaloa and Durango, respectively. It differs from the species of the subgenus Pseudolachnostoma by having a gynostegium with a reduced stipe, lobes of the corolla and sepals of shorter length than the tube, citrus aroma, and a dense inflorescence. We included photographic plates, and an illustration with the distinctive characters, as well as a dichotomous key for the species of the subgenus Pseudolachnostoma. Based on its reduced range and impacted habitat, it is considered a threatened species, according to IUCN criteria. Conclusions: With the present discovery, the genus Gonolobus reaches 45 species in Mexico with 24 endemics. Gonolobus gonzaleriarum has great ornamental potential considering its conspicuous inflorescences and pleasant citrus aroma, which could encourage strategies for its conservation, since it is found in a restricted distribution and threatened habitat.

Background and Aims: Most fruits of Psittacanthus mistletoes (Loranthaceae) depend on frugivorous birds for seed dispersal, and their spatial distribution patterns within and between hosts are strongly influenced by the behavior of seed dispersers. Despite the importance of birds in their dispersal and distribution, the effects of host species on fruit size variation have not been investigated to any large extent. The aim of this study was to characterize fruit size variation of Psittacanthus schiedeanus ripe fruits growing on different host species. We expect that the fruit size traits will vary according to the quality of host species, and that this variation will correspond to those in mistletoe reproductive success. Methods: Fully ripe fruits from Psittacanthus schiedeanus mistletoe plants growing on different host tree species were collected at two locations (Tlalnelhuayocan and Coapexpan) of cloud forest in central Veracruz, Mexico, measured (length and width and length of cupular pedicels) and weighed to describe fruit size differences. Key results: Cupular pedicel length and fruit size were significantly affected by host species. On average, longest cupular pedicels and larger fruits were found on plants growing on naturally growing Acacia pennatula, Quercus germana, Ostrya virginiana and Liquidambar styraciflua, whereas the smaller ones were found generally on cultivated host trees. Conclusions: The results provide us with valuable information for further species comparisons regarding the effects of host species on fruit size variation. Although the effects of host species on fruit size variation might vary across space, fruit size differences might be the result of host-resource differences. Further study on fruit selection and fruit handling by seed dispersers is needed to discuss whether the observed fruit size variation correlates with fruit selection and handling by main consumers, and with successful attachment and establishment to host branch after gut passage.

Background and Aims: Humaria (Pyronemataceae, Ascomycota) is an ectomycorrhizal genus of fungi, mainly distributed in temperate forest. It is characterized by cupuliform to discoid apothecia that are covered with abundant hairs throughout the exterior of the brown ascomata, and by ellipsoid, hyaline, warty ascospores. There are 66 accepted species of which only one has been recorded in Mexico. The present study aims to describe a new species of Humaria with morphological, ecological and molecular data, found in Quercus forests from Tamaulipas, Mexico. Methods: The specimens were collected in 2019 in the Victoria municipality, Tamaulipas, Mexico. Description and morphological studies were performed according to traditional mycological techniques. Studied material was deposited in the José Castillo Tovar Mycological Herbarium of the Instituto Tecnológico de Ciudad Victoria (ITCV) and the Escuela Nacional de Ciencias Biológicas Herbarium (ENCB) of the Instituto Politécnico Nacional. Phylogenetic analyses were performed using ITS and LSU sequences of the nuclear rDNA. Key results: Humaria setimarginata sp. nov. is described and illustrated. This species is well differentiated by its morphological, molecular and ecological characteristics. It forms typically cupuliform apothecia with straight margin, abundant dark brown colored short hairs at the margin, and a greyish-white hymenium. It presents a dextrinoid reaction in the ectal excipulum in contact with Melzer´s reagent. It grows around Quercus rysophylla and Q. polymorpha in oak forests. Conclusions: Humaria setimarginata is the second species of this genus reported in Mexico, after Humaria hemisphaerica. There are several collections under the name Humaria sp. that need a revision, to expand the diversity knowledge of this genus in this country. It is possible that several species exist, considering that this genus is ectomycorrhizal and the diversity of its potential hosts is high.