First record of Utricularia breviscapa C.Wright ex Griseb. (Lentibulariaceae) in Rio de Janeiro state, Brazil

Utricularia breviscapa C.Wright ex Griseb. belongs to the Lentibulariaceae, a family of carnivorous plants with many aquatic species. We report a new record of U. breviscapa in a perennial wetland along the São João River, in a Lowland Forest within the Atlantic Forest biome. This is the first record of this species from the state of Rio de Janeiro, southeastern Brazil. Utricularia breviscapa differs from the its aquatic congeners in South America by the presence of a whorl of 3–7 basally connate cylindrical floats at the base of the floral scape, and by the primary and secondary leaf-segments arranged into groups of threes.


Introduction
Utricularia L. (Lentibulariaceae, Lamiales) is a genus of aquatic, terrestrial, epiphytic, rheophytic, or lithophytic carnivorous herbs which display a sensitive utricle (prey trap) composed of modified leaves specialized in capturing and digesting small insects, aquatic microorganisms, and algae (Sirová et al. 2009;Guedes et al. 2020).Species of this genus form stolons and do not exhibit roots, but may bear rhizoids, which are anchorage organs that do not uptake nutrients from the substrate.Leaves are on the scape or rhizoid, aerial or submerged, filiform to circular, entire or divided into many filiform segments, and arranged in rosettes.The utricules are most commonly developed in stolons, but also in leaves and rarely in rhizoids.Inflorescences are emergent in aquatic and amphibious species, and the flowers are bilabiate with a spur (Taylor 1989).The genus comprises approximately 240 species in tropical and subtropical regions (Guedes et al. 2021).In Brazil, 71 species are distributed in all biomes, but only 20 are currently recorded from the state of Rio de Janeiro; two of them are endemic (Guedes et al. 2020).The state of Rio de Janeiro presents a great diversity and many endemic species, despite the marked deforestation and forest fragmentation (Myers et al. 2000;Ribeiro et al. 2009).The biodiversity in Rio de Janeiro is still poorly documented (e.g., Colli-Silva et al. 2020), highlighting shortfalls in biodiversity knowledge that hamper the accurate recognition of biodiversity patterns and predictions, as well as the effectiveness of conservation strategies (Hortal et al. 2015).Here, we report the first record of U. breviscapa from the state of Rio de Janeiro, where it was found in a small wetland in the Atlantic Forest biome.

Methods
Expeditions were carried out in the wetland Ribeirão das Crioulas (near the Biological Reserve Poço das Antas, Rio de Janeiro state, Brazil.Ribeirão das Crioulas is a perennial wetland area connected to the São João River, within a Lowland Forest of the Atlantic Forest biome.Samplings took place monthly between May 2019 and February 2020.However, the species was recorded only in May 2019, with a single flower found.The regional climate is hot and wet in summer and cold and dry in winter (Aw climate of the Köppen climate classification; Bernardes 1952).Specimens were stored in 70° GL alcohol, photographed, and deposited in the herbarium of Museu Nacional, R (Thiers 2021).We consulted GBIF (2021) and SpeciesLink ( 2021) platforms for records of U. breviscapa for building a geographical distribution map in QGIS.We only included records identified by taxonomic specialists in the group or records with digitized images enabling confirmation of the identifications.The description was based on collected material and the literature.Additionally, we recorded abiotic data for characterizing the habitat of the new record.Rainfall data were collected from the nearest weather station, transparency with Secchi disk, depth was measured with measuring tape, and water temperature and pH with Akso portable sensors.The area is dominated by Salvinia auriculata Aubl.(Salviniaceae), a free-floating species.
The species was recorded in a perennial wetland bordering the São João River and Juturnaíba dam, located in one of the rare fragments of the Lowland Forest in the Atlantic Forest biome.
Identification.In the Rio de Janeiro population, it was observed a spongy peduncle with a whorl of 4 spongy floats.There are 11 species of Utricularia with a leaf-life whorl on the base of the peduncle.Only three of them occur in Brazil: U. platensis Speg., U. benjaminiana Oliver, and U. breviscapa; the latter exhibiting a broader distribution than the former ones.Utricularia breviscapa differs from the other ones by having primary and secondary leaf segments arranged in threes.This species is most abundant in the Pantanal (Pott and Pott 2000) and the Amazon Forest, with rare occurrences in the Atlantic Forest (Guedes and Alves 2020).
Habitat.The new record comes from a eutrophic wetland bordering a large river within a Lowland Forest of the Atlantic Forest biome.During sampling expeditions, we recorded the following environmental conditions (minimum-maximum): 1-2 m depth, pH 5.1-8.1,photoperiods 10.8-13.5, rainfall 50-330 mm/month, transparency 0.2-1.5 m, and water temperature 18.7-31 °C.

Discussion
We recorded Utricularia breviscapa in the rainy season and only one flower in May 2019.It has low coverage and is locally rare.Utricularia breviscapa is usually found in wetland and shallow lakes in nutritionally poor, acidic waters (Juniper et al. 1989).Nevertheless, Ribeirão das Crioulas eutrophic and dominated by Salvinia auriculata, highlighting that U. breviscapa can occupy a wider environmental conditions than previously thought, including eutrophic ecosystems and basic waters.In the study area, we found another aquatic species of Utricularia, U. foliosa L., which differs from U. breviscapa by not having floats.
The occurrence of U. breviscapa in Rio de Janeiro state was thought to be unlikely, as the family was recently monographed in the state, and U. breviscapa was not reported (Baleeiro et al. 2017).The nearest record is approximately 300 km from Ribeirão das Crioulas, in the Rio Doce basin in Minas Gerais state.The IUCN Red List classified the species as Least Concern (Clarke 2018), even though Brazilian wetlands are highly threatened by human activities, such as urbanization and agriculture (Junk et al. 2014).The site of the new record is near one of the largest dams in Rio de Janeiro (Rocha and Neto 2018).Damming may favor species associated with lacustrine environments and disrupt macrophyte dispersal, compromising the distribution and long-term persistence of other species (Ceschin et al. 2015;Jones et al. 2020).

Figure 2 .
Figure 2. Distribution of Utricularia breviscapa.Occurrence data used in this map are presented in Appendix TableA1.