Chamaecrista exsudans (Benth.) H.S. Irwin & Barneby, Mem. New York Bot. Gard. 35: 650. 1982 Chamaecrista xanthadena (Mart. ex Benth.) H.S. Irwin & Barneby, Mem. New York Bot. Gard. 35: 650. 1982 Cassia exsudans var. xanthadena Mart. ex Benth. Cassia xanthadena (Mart. ex Benth.) H.S. Irwin & Barneby, Mem. New York Bot. Gard. 30: 58. 1978 Chamaecrista adamantina (H.S. Irwin & Barneby) H.S. Irwin & Barneby, Mem. New York Bot. Gard. 35: 650. 1982 Cassia adamantina H.S. Irwin & Barneby, Mem. New York Bot. Gard. 30: 57. 1978 Chamaecrista ixodes (H.S. Irwin & Barneby) H.S. Irwin & Barneby, Mem. New York Bot. Gard. 35: 650. 1982 Cassia ixodes H.S. Irwin & Barneby, Mem. New York Bot. Gard. 30: 59. 1978 Chamaecrista xanthadena (Mart. ex Benth.) Govaerts, World Checkl. Seed Pl. 3: 14. 1999 Chamaecrista amphibola (H. S. Irwin & Barneby) Irwin & Barneby (1982: 651) Cassia amphibola Irwin & Barneby (1978: 72) Chamaecrista setosa Chamaecrista setosa Chamaecrista setosa: A. Flowering Chamaecrista amphibola Absus subsect. Absus ser. Setosae Setosae Ursinae Ch. amphibola Ch. exsudans Ursinae Ch. amphibola Ch. exsudans Ch. exsudans C. amphibola New taxonomic circumscription to Chamaecrista ser. Setosae (H. S. Irwin & Barneby) H. S. Irwin & Barneby (Leguminosae, Caesalpinioideae) Oliveira, Jaqueline Aparecida De Mendes, Thainara Policarpo Souza, Alessandro Oliveira De Silva, Marcos José Da Phytotaxa 2021 2021-03-12 490 2 118 158 5XPTL (Benth.) H. S. Irwin & Barneby, Mem. H. S. Irwin & Barneby, Mem. Benth. [136,845,1382,1409] Magnoliopsida Fabaceae Chamaecrista Plantae Fabales 34 152 Tracheophyta species exsudans   Campo, 1839, (fl), Claussen 25( lectotype: K-00055549, designated by Bentham in Martius(1870), isolectotype: P- 00836007).  =   Chamaecrista xanthadena(Mart. ex Benth.) H.S. Irwin & Barneby, Mem.New York Bot. Gard. 35: 650. 1982. Cassia exsudans var. xanthadena Mart. ex Benth.in Mart., Fl. Bras. 15: 152. 1870.   Cassia xanthadena(Mart. ex Benth.) H.S. Irwin & Barneby, Mem.New York Bot. Gard. 30: 58. 1978. Type:— BRAZIL: Minas Gerais: “Inter distr. Adamant. et Sa. de S. Antonio, in vepretis siccis deserti”, August 1818, (fl), Martius 1508 ( holotype: M-0217529, M-0217530). =   Chamaecrista adamantina(H.S. Irwin & Barneby) H.S. Irwin & Barneby, Mem.New York Bot. Gard. 35: 650. 1982.   Cassia adamantinaH.S. Irwin & Barneby, Mem.New York Bot. Gard. 30: 57. 1978. Type:— BRAZIL: Minas Gerais: Diamantina,  June 1934, (fl, fr), Brade 13677 ( holotype: RB-00539426, RB-00545310, isotype: NY-00003703). =   Chamaecrista ixodes(H.S. Irwin & Barneby) H.S. Irwin & Barneby, Mem.New York Bot. Gard. 35: 650. 1982.   Cassia ixodesH.S. Irwin & Barneby, Mem.New York Bot. Gard. 30: 59. 1978. Type:— BRAZIL: Minas Gerais: Itamarandiba, Chapada de Itamarandiba,  June 1960, (fl, fr), Mendes-Magalhães 18053 ( holotype: NY-00003821). =   Chamaecrista xanthadena(Mart. ex Benth.) Govaerts, World Checkl. Seed Pl.3: 14. 1999. Nom. illeg.  =   Chamaecrista amphibola(H. S. Irwin & Barneby) Irwin & Barneby (1982: 651). ≡   Cassia amphibola Irwin & Barneby (1978: 72), Type:— BRAZIL. São Paulo: in campis, Vila Franca [ca. 47°W, 2 r s], June 1834, (fl.), Riedel s.n.[ holotype: Sheet 1 (LE00002283!), Sheet 2 (LE00002284!), isotype: NY00003710!]. Syn. nov.   FIGURE 21:  Chamaecrista setosa: A, B.and C.Diversity of habits and habitats, note the variation in habit and growth and effuse inflorescence; D.Portion of the main stem, showing the plagiotropic leaves and vinaceous trichomes; E.Detail of indumentum of the branch; F.Foliage, note the ascending leaves; G.Leaf.   FIGURE 22:  Chamaecrista setosa: A.and B.Inflorescences, note the aspect effuse suberect or pending, with main axes green or vinaceous, and bus nutant; C.and D.Detail of Indumentum of the inflorescence and buds; E.and F.Flowers in frontal view, note the sepals externally yellowish with a central spot vinaceous or completely vinaceous, the apex shortly acuminate or acute; G.Fruit.   FIGURE 23:  Chamaecrista setosa: A.Floweringbranch; B.Detail of indumentum of the branch; C.Detail of the indumentum of inflorescence; D.Stipule; E, F, Gand H.Leaflets shapes; I.Detail of surfaces of the leaflets; J.Bracts; K.Bracteole; L.Bud; M.Flower in frontal view; N.Sepal; O.Petals; P.Androecium and Gynoecium; Q.Stamen; R.Gynoecium; S.Fruit; T.Detail of Indumentum of the fruit; U.Seeds ( J.A. Oliveira 15 and 110—UFG).   Chamaecrista amphibola, included formerly in Ch.sect.  Absussubsect. Absusser. Setosae, is known only from its typuscollection. It was described by Irwin & Barneby (1978)who cited that its could be an intermediate specimen (hybrid) between some taxa belonging to the series  Setosaeand  Ursinae. After its description,  Ch. amphibolawas never collected again and analyzing the morphology of its typuscollection, we concluded that it is more similar to  Ch. exsudansfrom the series  Ursinaethan other species of Setosae, mainly for having 3 or more pairs of leaflets and abundant stellate trichomes in vegetative and reproductive parts, which led us to consider  Ch. amphibolaas a synonym for  Ch. exsudans. Considering that both species were described in the same work, and that  Ch. exsudansis a more collected and known taxon than  C. amphibola, we opted for the binomial as valid. [136,1451,1418,1445] Benth., J. Brazil Cachoeira Ouro Preto 34 152 1 Minas Gerais [136,1451,1454,1481] Bentham in Martius 34 152 1 lectotype [642,918,1674,1696] 1934-06 Brazil Diamantina Type 34 152 1 Minas Gerais holotype [590,866,1782,1804] 1960-06 de Itamarandiba Brazil Chapada de Itamarandiba 34 152 1 Minas Gerais holotype