Bromeliaceae exhibits significant pollen diversity. Within the family, pollen grains are dispersed either as monads or tetrads and may be monosulcate, bi-, tri-, tetra-, or pantoporate, or even inaperturate. Ornamentation includes reticulate, foveolate, microreticulate, perforate, or psilate patterns. Additional variations are observed in the margins of the apertures and in the exine deposition on the aperture membrane. In general, pollen grains are relatively well-documented in Bromeliaceae. However, there is a lack of systematization and organization to provide a comprehensive and integrated understanding of its pollen structure. This study aims to conduct a general review of pollen morphology in Bromeliaceae, analyze character diversity based on the current phylogeny of the family, and propose the ancestral states of pollen traits. The study sampled 127 species from 47 genera, supplemented by literature data of 220 species (from 14 additional genera). Together, this dataset encompasses over 70
Fabaceae (Leguminosae) is one of the most species-rich and ecologically important angiosperm families, encompassing extraordinary diversity in growth form, floral architecture, fruit morphology, and symbiotic nitrogen fixation. Despite the central role of MADS-box transcription factors in controlling key developmental processes underlying these traits, their evolutionary history in legumes remains poorly understood. Here, we present a comprehensive phylogenetic and comparative genomic analysis of MIKCc MADS-box genes across Fabaceae, sampling representatives from three of the six subfamilies and spanning major evolutionary lineages using genomic and transcriptomic data. Our analyses reveal that all type II MIKCc MADS-box gene lineages known from angiosperms are represented in Fabaceae, except for TDR8 homologs. However, several clades, including MAF/FLC, AGL16/17/ANR1, ABS, and XAL1, are consistently poorly represented, suggesting lineage-specific constraints or gene loss. While numerous MADS-box genes remain single copy across most legumes, others show duplications prior to the diversification of Fabaceae, including AGL6, AGL24b, PI, SEP, and SOC1. Subfamily-specific expansions were detected in key developmental regulators, with duplications of AGL14/19-like, FUL, TM6, and SOC1 in Caesalpinioideae, and AG, AGL6, AGL79, AP1, FUL, and SEP lineages in Papilionoideae. These patterns coincide with documented whole-genome duplication events in both subfamilies. In addition, pervasive gene duplication in Glycine reflects a genus-specific polyploidization history. Together, these results suggest that differential retention and loss of duplicated MADS-box genes have played a central role in shaping floral and inflorescence diversity, phenological variation, and ecological adaptation in legumes. By integrating phylogenetic patterns with existing functional data, this study provides an evolutionary framework for understanding how MADS-box gene diversification has contributed to the remarkable developmental and adaptive radiation of Fabaceae.
The Caatinga harbors the largest continuous expanse of Seasonally Dry Tropical Forests and Woodlands (SDTFW) in South America, characterized by a highly diverse flora and a significant number of endemic species. In this study, we compiled data on species distribution within the Caatinga by gathering information from 112 peer-reviewed floristic and phytosociological studies published up to December 2020. We characterized this database by identifying woody and non-woody species, checking their International Union for Conservation of Nature (IUCN) Red List status, highlighting the families represented by most species, and analyzing species distribution across Neotropical biomes, biogeographical districts, and Holdridge life zones. Our database includes 1,775 taxa identified at the species level (conservative richness), while the total estimated richness was 2,978 species, including unidentified specimens. However, our analysis revealed that the proportion of unidentified taxa in Caatinga studies decreased from 27.10
This study integrates and updates the ethnobotanical knowledge of Asteraceae in the Yucatán Peninsula, Mexico. A comprehensive literature review was conducted, complemented by descriptive methods such as interaction networks and use value indices, to assess the associations between species and their uses, as well as ecological and distributional aspects. A total of 126 Asteraceae taxa with ethnobotanical uses were identified, of which 84 are native (including 12 endemic). Thirteen categories of use were documented, with melliferous (86 species) and medicinal (66 species) being the most prominent. Ecologically, in the region the majority of Asteraceae species are herbaceous (68.8
Fern hybrids, a remarkable proportion of which are sterile, provide the basis for hypotheses for species-level divergence between hybrid progenitors using the biological species criterion. Thus, these hybrids can be used to distinguish taxa in complex arrays of understudied and cryptic species. Qualitative morphological features such as anomalies in spore shape, size, and color have often been used to infer sterility as part of identifying fern hybrids. To establish a protocol for quantitative distinction of species and hybrids using spore variation in size and shape, we used spore length and width data originating from an array of 30 genetically profiled specimens of species and 11 of hybrids in the fern genus Polystichum. To assess the possibility of inferring working hypotheses for circumscriptions of species and hybrids using the quantitative data alone, we used a separate set of spore length and width data from a set of 17 type specimens of Polystichum, all without genetic profile. Using the genetically profiled plants, we found that the best quantitative representations of spore variation for distinguishing hybrids from species were coefficients of variation for length and shape (= length/width). These statistics yielded hypotheses for hybrids and species in the type-specimen dataset. The approach developed here is likely to be useful for testing hypotheses for species and hybrids across the ferns, notably in complex arrays including cryptic species, using the biological-species criterion.
