The semiarid region of northeastern Brazil possesses a set of wetlands characterized by hydrographic basins with deficient drainage networks, a few large and permanent lotic systems and several permanent and temporary lagoons. Aquatic plants are widely distributed in these wetlands and the present study aims to determine if those of Ceará state have similar species compositions and differences in species richness. We hypothesized that lentic ecosystems would have more species and different growth forms of aquatic angiosperms than lotic ecosystems. A total of 1619 records of aquatic angiosperms in 43 wetland areas were analysed. The most representative families were Cyperaceae, Poaceae, Fabaceae, Alismataceae, Malvaceae, Nymphaeaceae and Pontederiaceae. Most of the species are helophytes and bottom-rooted emergent hydrophytes. Permanent lentic ecosystems had the highest number of exclusive species (27.85 %), followed by temporary lentic ecosystems (20.54 %). Contrary to our hypothesis, the different aquatic ecosystems were found to possess distinct species compositions and different proportions of growth forms, and all wetland types contributed to the macrophyte richness of the study area, although they differ in species richness. Therefore, conservation plans for the native aquatic macrophyte biota should include all wetland ecosystems in the semiarid state of Ceará.

The present study analyzed taxa of the family Cabombaceae occurring in the state of Ceará. Only Cabomba species was represented, with C. aquatica and C. haynesii recorded in the state. Populations occur in permanent and temporary lentic environments, such as lagoons and shores of lotic systems. This work presents taxon identification keys, morphological descriptions, illustrations, comments and geographic distribution data.

This floristic survey of Alismataceae from the state of Espírito Santo aims to update the diversity and extinction vulnerability data for the species. The taxa here listed were obtained from Splink and Reflora Virtual Herbarium databases. A total of seven native taxa were registered for Espírito Santo state: Echinodorus grandiflorus, E. macrophyllus, Helanthium bolivianus, Hydrocleis nymphoides, Limnocharis flava, Sagittaria lancifolia and S. rhombifolia; the exotic species Alisma plantago-aquatica presented one single record. The populations occurred in flooded areas located at low altitudes and were primarily collected from some preserved areas and in the coastal region of the state. This study presents a taxonomic identification key, morphological descriptions and species illustrations. Comments on ecology, conservation and geographical distribution of the species are also presented.

This study aimed to provide the floristic survey of Onagraceae in Ceará state. The floristic study consisted of analyzing material deposited in the herbaria EAC, ESA, FUEL, HCDAL, HUEFS, HUVA, HVASF, INPA, K, MO, NY, P, RB, UFRN and US, as well as field work carried out between 2015 and 2017. In the study area, Onagraceae is represented by the genus Ludwigia, and seven species were recorded: L. erecta, L. helminthorrhiza, L. hyssopifolia, L. leptocarpa, L. nervosa, L. octovalvis and L. tomentosa. All seven species were also sampled in Conservation Units, with L. erecta recorded in six of them. L. erecta and L. helminthorrhiza have a broader distribution in the state. L. nervosa and L. tomentosa are indicated as new occurrences for Ceará, both with only one record in the south of the state, expanding their range in Northeastern Brazil. The information in this manuscript allows identification of Onagraceae representatives in Ceará state, through morphological descriptions, identification keys, taxonomic comments, illustrations, photographs and geographic distribution data.