Bignoniaceae in the Raso da Catarina Ecoregion , Bahia , Brazil

This work presents a floristic survey of the family Bignoniaceae in the Raso da Catarina Ecoregion, Bahia, Brazil, considered as the main family of the Brazilian forests lianas. The samples analyzed were collected from September 2012 to May 2014. The analyses were supplemented with botanical collections kept in the herbaria: ALCB, HRB, HUEFS, IPA and PEUFR. The identifications were made based mainly on specialized bibliographies, protologues, photos of type collections and consulting of the collections in the herbaria that were visited. 11 genera and 20 species of the family were recorded. Fridericia Mart. and Handroanthus Mattos were the most representative genera (5spp.), followed by Jacaranda Juss (2spp.). The other genera presented only one species each. The most representative species in the area were: Anemopaegma laeve DC., Fridericia erubescens (DC.) L.G.Lohmann, Jacaranda jasminoides (Thunb.) Sandwith. and Tabebuia aurea (Manso) Benth. & Hook f. ex Moore. Among the species registered one is new record for the Caatinga biome, ten are endemic to Brazil and three exclusive of the Caatinga. The taxonomic treatment includes a key for the identification, descriptions, illustrations, photos, data of the geographical distribution, economic potential and reproductive phenology and comments about the species.


Introduction
Bignoniaceae with 827 species allocated in 82 genera (Lohmann & Ulloa 2007), has a predominantly Neotropical distribution with its center of diversity in Brazil (Gentry 1980).The species occur in a variety of environments, from open savannas to humid and perennial forests, and represent the main family of lianas in Brazilian forests (Silva & Queiroz 2003), where 413 species and 33 genera are recorded (Lohmann 2015).
The family is included in the order Lamiales (APG IV 2016) based on molecular phylogenetic studies.With the exclusion of the tribe Schlegelieae and the genus Paulownia Siebold & Zucc., which were included in the families Schlegeliaceae and Paulowniaceae, respectively, Bignoniaceae is considered monophyletic, with the synapomorphies of: absence of endosperm, composite leaves, and seeds with hyaline wings surrounding the embryo (Spangler & Olmstead 1999, Olmstead et al. 2009).
After studies involving tribal and intergeneric delimitations, seven clades can be recognized for the family: Bignonieae, Catalpeae, Oroxyleae, Tecomeae, Tourrettieae, Jacarandeae and Crescentiina.This last group is inserted the clade informally denominated of Tabebuia Alliance, a Neotropical lineage formed by the tribe Crescentieae and by genera segregated from the tribe Tecomeae (Grose & Olmstead 2007, Olmstead et al. 2009).Among these groups, we highlight Bignonieae as the largest tribe of Bignoniaceae, and which underwent taxonomic rearrangements after molecular phylogenetic studies resulting in the proposal of synonyms, new combinations and recircumscriptions of genera.Currently it includes 393 species and 21 genera (Lohmann & Taylor 2014), and is the most diverse and abundant group of lianas in tropical forests of the New World (Gentry 1986).The tribe constitutes a monophyletic lineage strongly supported by molecular and morphological data (Spangler & Olmstead 1999, Olmstead et al. 2009).
In addition to its great ecological importance, the family also possesses economic value expressed mainly by species with wood potential.Additionally, trees are ornamental when flowering, and are popular species for use in landscaping in Brazil, while some are still used to cover gates and fences in reforestation areas or in popular medicine (Gentry 1992a, Lorenzi 2008, 2013).
Important studies on the group in the Northeast Region of Brazil have been performed, however, studies on taxa of Bignoniaceae in areas of Caatinga in Bahia, including identification keys and descriptions are few.Given the significant rate of endemism and diversity for the Caatinga biome, and the limited number of surveys for the family therein, this study aims to contribute to a better understand of the family in the Raso da Catarina Ecoregion (Bahia portion), in order to contribute to the knowledge of the local flora and to provide support for the development of management plans for the conservation units (CUs) of this ecoregion.

Material and Methods
The Raso da Catarina Ecoregion comprises 30.800 km 2 and is one of the eight Ecoregions recognized for the Caatinga.In the North-south direction it is narrow and elongated.In the North, West and East it is limited to the southern hinterland depression.The northeastern portion has limits with the Borborema Plateau and the southern part of the Bahia hinterland, in the Zona da Mata.The Ecoregion is a basin with soils that are very sandy, deep and little fertile.Its relief is very flat, but with canyons in the western part (formed by sandstone outcrops).
The altitudes above sea level vary from 400 to 600 m in the southern part (Bahia) and from 350 to700 m in the northern part (Jatobá basin, Pernambuco).In the southern part (Bahia) most of the soils are composed of sand (deep, excessively drained, acid and very low fertility) and oxisol (deep, well drained, acid and low fertility) whereas in the northern part (Pernambuco) sands soils prevail.There exists little surface water in the region except in the areas of the canyons.The predominant vegetation is the sandy, bushy Caatinga, very dense and less thorny than the Caatinga of crystalline soils (Velloso et al. 2002).
The climate of the Ecoregion is semiarid with average rainfalls of 650 mm/year in the southern part (Bahia) and rainy season from December to July.In the northern part (Pernambuco) the climate is drier with average rainfalls of 450 mm/year and the rainy period is from January to April.The ambient temperatures are very high with large differences of temperature between day and night.The soils are generally sandy deep and very fertile relief plan with sandstone formations and the predominant vegetation is the sandy, bushy Caatinga, very dense Figure 1.Location of conservation units of the Ecoregion Raso da Catarina, state of Bahia, Brazil (Varjão et al. 2013, modified).
(continuously updated; Appendix 1).The field collections and observations were performed during random walks exploring most of the study area.Herborization and material processing followed the methodology by Fosberg & Sachet (1965) and Mori et al. (1989), where fertile material was collected with flowers and/or fruit.Observations were made about the distribution of the species and the type of soil (Sampaio 1995, Tricart 1972).The specimens were deposited in the herbarium HUNEB -Paulo Afonso Collection and the duplicates will be sent to the main herbaria in the state of Bahia.
In the RCE (southern part) 11 genera and 20 species were catalogued for the family.Fridericia Mart.and Handroanthus Mattos with five species, were the most representative genus, followed by Jacaranda Juss., with two species.The other genera presented only one species each.The most representative species in the area were: Anemopaegma laeve DC., Fridericia erubescens (DC.)L.G.Lohmann, Jacaranda jasminoides (Thunb.)Sandwith.and Tabebuia aurea (Manso) Benth.& Hook f. ex Moore.

Cuspidaria lateriflora
In the area, the species can be recognized by small (ca.2.5 × 2 cm) leaflets with tector and glandular stipitate trichomes, which are of a sticky consistency in the fields, bracts, calyx with cuspidate lobes, glandular trichomes stipitate, anthers with thecae forward-curved, slightly pubescent and capsule linear striated.
Dolichandra quadrivalvis can be identified by tendrils trifid, with uncinate tips, bracts and bracteoles foliaceous, flowers with spathaceous calyx, with a recurved apicule and yellow corolla.

Fridericia limae
The species can be recognized by chartaceous leaflets, with slightly urceolate, truncate calyx and corolla white passing to cream and linear and compressed capsule.In the field, it is also possible to smell the sweetish odor released by the flowers.
This species is endemic from Brazil, recorded to Alagoas, Bahia, Ceará, Paraíba, Pernambuco, Rio Grande do Norte, Sergipe, Mato Grosso do Sul and Minas Gerais (Lohmann & Taylor 2014, Lohmann 2015).It is distributed through environments of Caatinga, Cerrado and Atlantic Forest (Lohmann 2015).The species is underrepresented in the study area, it was collected three times and recorded only to one conservation units: EBC.It flowers from April to May.
Fridericia parviflora is easily recognized by leaflets with membranaceous consistency and mainly by crenate margins.
Fridericia pubescens spreads in dry to humid forest vegetation distributed from Mexico to Brazil (Lohmann & Taylor 2014), found in Amazon Rainforest, Caatinga, Cerrado, Atlantic Forest and Pantanal (Lohmann 2015).It was collected only once in the municipality of Ribeira do Pombal in an open field.It was found with flowers in January.
In the study area it can be differentiated from the other congeners because it presents pubescence distributed throughout the plant, interpetiolar glands conspicuous, leaflets strongly discolorous with abaxial face densely pubescent and small corolla of 2-2.5 × 1-1.5 cm.
The species occurs in the northeast, southeast and south of Brazil with records Cerrado and Atlantic Forest (Lohmann 2015), being distributed by the coastal region of Brazil, recorded for restingas, open forests and disturbed forests, widely used as ornamental (Gentry, 1992b).In the Ecoregion the species is underrepresented, collected only once with flower and few very young leaves, in an area of slope.It was collected with flowers only in January.
Handroanthus grandiflorus is a species critically endangered, endemic from Caatinga, with records for the state of Bahia, its geographic distribution can also be used to distinguish it from the morphologically most similar species, which predominantly occur in more humid regions (Espírito Santo et al. 2012).In the study area it is underrepresented, with only two individuals registered.It was collected with flowers in October.
In the Ecoregion the species can be confused with other congeners that also present yellow flowers.However, it differs from the flowers with a broadly campanulate calyx, sparsely stellate-tomentose and corolla with ca.11 cm.
The species is widely distributed from El Salvador to Northwest Argentina (Gentry 1992b).In Brazil It occurs from the north to the south of Brazil, in environments of Amazon Rainforest, Atlantic Forest, Caatinga and Cerrado (Lohmann 2015).In the studied ecoregion, it is poorly represented, having been collected only twice.It was collected with flowers in October.
In the study area, H. ochraceus is recognized by obovate to elliptic discolorous leaflets, with adaxial surface green and lepidote, abaxial surfaces whitish-cream, densely stellate-tomentose and greenferruginous calyx, densely vilose, with trichomes stellate and dendroid.
The species is found from Colombia to Bolivia, Guianas and Brazil.In Brazil, it has a wide distribution from the north to the south, with records for the Amazon Rainforest, Caatinga, Cerrado, Atlantic Forest and Pantanal (Gentry 1992b, Lohmann 2015).It is underrepresented in the study area, with only one individual registered.It was collected with flowers in December.
Handroanthus serratifolius can be easily identified by lepidote leaflets with trichomes restricted tectores the midrib or between the midrib and secondary, margins entire passing to the serrated at the apex, glabrous calyx to sparse pubescent, tector trichomes and adpressed stellate and ovary glandular-verrucose.According to Espírito Santo et al. ( 2013) it is a polymorphic species.According to Lohmann (2015) Jacaranda brasiliana is endemic to Brazil, distributed from the north to the southeast, in environments of Amazon Rainforest and Cerrado.Therefore, this work provides a new occurrence for this species in the Caatinga environments.In the studied Ecoregion is represented by few individuals.Flowers and fruits from November to January.
Species recognized by the presence of bipinnate leaves, leaflets small with base asymmetric cuneate, calyx deeply lobed, anthers 1thecate and woody capsules with margins broadly undulating.
Jacaranda jasminoides is endemic to Brazil with records for the states of Alagoas, Bahia, Ceará, Paraíba, Pernambuco, Piauí, Rio Grande do Norte, Sergipe, Espírito Santo, Minas Gerais and Rio de Janeiro.It is distributed through environments of Caatinga, Cerrado and Atlantic Forest (Lohmann 2015).Species easily found by area.It flowers and fruiting the whole year.
This species is characterized by branches with pinnate leaves at base and bipinnate leaves at apex, leaflets with margins entire or serrate, flowers vinaceous-magenta with white nectar guides on the fauces, glandular-pubescent staminode ca.30 mm, and capsule ovate to obovate with flat margins.17.Lundia longa DC., Prodr.[A.P. de Candolle] 9: 180.
In the study area the species can be clearly differentiated from the others by lanceolate to cordate leaflets, flowers with pink to red corolla and yellow fauces, nectariferous disk absent, ovary, anthers and connective pilose.