The family Bignoniaceae in the Environmental Protection Area Serra Branca, Raso da Catarina, Jeremoabo, Bahia, Brazil

Bignoniaceae comprises 82 genera and 827 species distributed mostly in tropical and subtropical regions, with a few species in temperate climates, and is most diverse in South America. The Brazil is the center of diversity for the group, with about 406 species in 33 genera, of which 22 genera and 90 species occur in the Caatinga. The floristic survey of Bignoniaceae in the Environmental Protection Area Serra Branca included analysis of 31 specimens collected from August 2009 to February 2012. The analyses were supplemented with dried collections from the following herbaria: ALCB, HRB and HUEFS. Nine genera and 11 species were recorded: [Anemopaegma Mart ex DC; Bignonia L.; Cuspidaria DC.; Fridericia Mart.; Handroanthus Mattos; Jacaranda Juss; Lundia DC.; Mansoa DC. and Tabebuia Gomes ex DC.]. Fridericia was the most representative genus with three species. The taxonomic treatment includes a key for the identification, descriptions, illustrations, photos, data of the geographical distribution, reproductive phenology and comments about the species.


Introduction
Bignoniaceae comprises 82 genera and 827 species distributed mostly in tropical and subtropical regions, with a few species in temperate climates, and is most diverse in South America (Lohmann & Ulloa, 2007;Judd et al., 2009).According to Gentry (1990), it is the most ecologically important liana family in the American tropics, and so constitutes a good model for studying the great diversity of tropical plant communities.Brazil is the center of diversity for the group with about 406 species in 33 genera, of which 22 genera and 90 species occur in the Caatinga (Lohmann, 2015).Giulietti, Conceição, and Queiroz (2006) considers Bignoniaceae to be the eighth most representative family of the Caatinga.Among the works carried out on taxa of Bignoniaceae in the Northeast Region of Brazil, we highlight the following: Harley and Simmons (1986) recorded three species in the region of Mucugê (Bahia); Gentry (1995) recorded six species at Pico das Almas, Chapada Diamantina; Lohmann and Pirani (1996) identified 17 species of the formerly tribe Tecomeae in the Cadeia do Espinhaço (Bahia and Minas Gerais); Silva and Queiroz (2003) recorded 33 species in Catolés, Chapada Diamantina, Bahia; Silva-Castro, Costa, and Brito (2007) recorded 15 species of Jacaranda in Bahia and Espírito Santo, Silva-Castro, and Rapini (2013) recognized 26 species in their taxonomic treatment of the Tabebuia Alliance.
The Caatinga has a high rate of endemism and diversity, making a better understanding of its flora necessary for proper conservation measures (Prado, 2003).However, Caatinga is probably the most undervalued and poorly known botanically biome (Giulietti et al., 2002), yet is has the lowest number of conservation units and is one of the least protected in Brazil (Leal, Silva, Tabarelli, & Lacher, 2005).
Studies on taxa of Bignoniaceae in areas of Caatinga in Bahia 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 Bignoniaceae in the Caatinga.Towards this aim, a survey of species of Bignoniaceae was conducted in the Environmental Protection Area Serra Branca, Raso da Catarina, to contribute to the knowledge of Angiosperms of the Caatinga in Bahia, as well as support the development of the area's management plan.

Material and methods
The Evironmental Protection Area Serra Branca, Raso da Catarina (EPASB, Figure 1) comprises 67,237 ha, located in the municipality of Jeremoabo in Northeastern, in the State of Bahia, and it is fully inserted into the "polígono das secas" (Fundação CTI/NE, 2016), delimited by the coordinates 09º53 '15.5'' to 09º44'34.6''S and 38º49'36.1'' to 38º52'20.4''W,limited to the South with the Vaza-Barris River and North to the Ecological Station Raso da Catarina (ESRC).The predominant vegetation is the sandy, very dense bushy Caatinga.The climate of the Ecoregion is semiarid, with average rainfalls of 500 mm year -1 and annual temperature is approximately 23ºC (Szabo, Rocha, Tosato, & Barroso, 2007).The soils are generally sandy deep and very fertile relief plan with sandstone formations (Velloso, Sampaio, & Pareyn, 2002).
The study was based on fieldwork carried from August/2009 to February/2012.Additional information was complemented by the analysis of specimens deposited in the following herbaria: ALCB, HRB and HUEFS (acronyms according to Thiers (2016) continuously updated).The field collections and observations were performed during random walks exploring most of the study area.The herborization and material processing followed the methodology by Fosberg and Sachet (1965); Mori, Silva, Lisboa, and Coradin (1989), where fertile material was collected with flowers and/or fruit.The specimens were deposited in the herbarium of the Universidade Estadual da Bahia (HUNEB -Collection Paulo Afonso) and the duplicates will be sent to the main herbaria in the State of Bahia (ALCB, HRB and HUEFS).
Bignonia convolvuloides is found in dry forest vegetation in Bolivia, Paraguay and Brazil [Bahia, Mato Grosso, Minas Gerais and Pernambuco] (Lohmann & Taylor, 2014).In Brazil is distributed in areas of Cerrado and Atlantic Forest (Lohmann, 2015).
In the EPASB it was collected in full bloom in November and December and found only in areas of well-preserved forest.
This species is recognized by branches with bromeliad-like prophylls, calyx with apiculate lobes, nectariferous disk inconspicuous and ovary papillate.Cuspidaria lateriflora is found in dry to wet forest vegetation in Peru Bolivia, Paraguay, and Brazil where is distributed in Amazon Rainforest, Caatinga, Cerrado, and Atlantic Forest (Lohmann & Taylor, 2014;Lohmann, 2015).It can be easily found throughout the study area where it flowers and fruits much of the year, peaking bloom between November and January.

Cuspidaria lateriflora
This species is recognized by relatively small (ca.2.5 × 2 cm) leaflets with tector and glandular stipitate trichomes, which are of a sticky consistency in the fields, filiform bracts, calyx with cuspidate lobes, glandular trichomes stipitate, stamens with forward curved anthers and capsule linear striated.
Fridericia dichotoma is widely distributed on slopes of tropical dry forest and humid forest (Lohmann & Taylor, 2014).It occurs from Mexico to Argentina, with extremely variable blooming during the dry season (Gentry et al., 1973).In Brazil there are records from Caatinga, Cerrado, Atlantic Forest, Pantanal and Amazon Rainforest from the north to the southeast regions (Lohmann, 2015).In the EPASB it was collected in full bloom in December and is poorly represented in the area having been collected only twice.
The species can be recognized by membranaceous leaflets, truncate calyx, tomentose corolla, lilac with magenta lobes and white fauces.
It is characterized by obovate leaflets, corolla red to orange passing to pink after pollination, stamens exserted and fruits with winged margins.
Fridericia limae is characterized 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.
Handroanthus impetiginosus is distributed from northwestern Mexico to northwestern Argentina, mainly in deciduous, semideciduous and seasonly dry forests (Gentry, 1992b).It is widely distributed in Brazil being recorded in Caatinga and Atlantic Forest from the north to the southeast (Lohmann, 2015).In EPASB it blooms and bears fruit from October to January.The species is well represented in the area and widely used as an ornamental.
This species is found in wet sites in Atlantic forest vegetation in eastern Brazil (Lohmann & Taylor, 2014).In Brazil it is distributed widely in Caatinga, Cerrado, and Atlantic Forest environments (Lohmann, 2015).In the EPASB it was collected in flower in July and is well represented.
Tabebuia aurea is typical of Brazilian Cerrado, with records also from areas of Caatinga, Mata Atlantica, Pantanal, and Amazon Rainforest, occurring from the north to the southeast (Lohmann, 2015).It is also distributed in seasonal forests of Argentina, western Bolivia, and southeastern Suriname (Gentry, 1992a).In the EPASB it was collected in full bloom in November.This species is well distributed in the area and is widely used as an ornamental in the region.
It is characterized by digitate leaves with lepidote indumentum, flowers with bilabiate calyx, lepidote and corolla yellow with red or brown nectar guides on the fauces.

Conclusion
Eleven species of nine genera were cataloged from the EPA Serra Branca, among these 27% are endemic to the Caatinga.Most species are widely distributed over the area.The genus most represented in the EPASB is Fridericia Mart., with three species.All other genera were represented by only a single species.The species with the most occurrences were: Anemopaegma laeve, Fridericia erubescens and Jacaranda jasminoides, while the species with lower occurrence were: Fridericia dichotoma and Bignonia convolvuloides.The peak flowering for the group encompasses the months of November to early February.