Chamaecrista carobinha (H.S. Irwin & Barneby) Irwin & Barneby (1982: 661)

Souza, Alessandro Oliveira De, Cavalcante, Raphael Guarda & Silva, Marcos José Da, 2022, Taxonomic revision of Chamaecrista sect. Absus subsect. Absus (Leguminosae, Caesalpinioideae) with adjustments in the new classification, Phytotaxa 565 (1), pp. 1-82 : 34

8. Chamaecrista carobinha (H.S. Irwin & Barneby) Irwin & Barneby (1982: 661)

≡ Cassia carobinha Irwin & Barneby (1978: 270) .

Type:— BRAZIL. Bahia: Juazeiro, February 1912 (fl.), A. Löfgren 891 (holotype RB00539437!, isotypes NY01529148!, RB00545299!) . (Figs. 15 and 16)

Subshrub perennial, prostrate, creeping or decumbent with supporting branches, in this case, plants up to 10 cm tall. Root nodules absent. Branches brown or green-yellow, puberulent indumentum with sparse or absent glandular trichomes, including stipules, petiole and rachis; non-exfoliating bark. Stipules 1.5–2.5 × 0.4–0.5 mm, linear or lanceolate, persistent. Leaves alternate-spiral, regularly distributed on the stem, plagiotropic or ascending; petiole 1.3–3(3.5) cm long; rachis 0.5–1.6(2) cm long; leaflets 2 pairs, 0.9–3.7(–4.5) × 0.5–2(2.3) cm, distal pair slightly larger than proximal pair, elliptical, oblong-elliptical or oval, apex obtuse, rounded or emarginate and mucronulate or not, asymmetrical base on the distal pair and rounded or slightly asymmetrical on the proximal pair, papyraceous, discolored, adaxial face dark green, sometimes vinaceous and puberulent, abaxial face opaque green, villosule and sparsely setulose-viscous; margin entire, revolute and ciliate; secondary veins 4–6 pairs, conspicuous and slightly prominent on abaxial surface. Leafy appendix inter-petioluleabsent. Racemes (7)10–35(–60) cm long, sessile or falsely pedunculated due to early fall of the first flower, 20–45 flowers, lax, terminal, generally with the flowers all oriented to the same side and opposite the ground, decumbent, suberect or pendant with slightly curved or sinuous axis, setulose-viscous and villous, including pedicel, external surface of bracts, bracteoles and sepals. Bracts 1.5–2 × 1 mm, triangular, persistent. Bracteoles 1–2 × 0.5 mm, or lanceolate, persistent. Buds 5–8 × 3–4 mm, ovoid or globoid, apex acute or obtuse.Flowers 2.5–4.5 × 2–3.7 cm; pedicel 1–3.3 cm long, straight, ascending or recurved when fruited; sepals 9–11 × 3.5–4 mm, elliptical, apex acute or obtuse, green or with vinaceous macules externally; 4 flat, oboval or oblong-oboval petals and 1 falcate-curled inner petal, 1.3–1.7 × 0.5–1 cm, yellow; stamens 10.5– 6 mm long, anthers not barbulate; ovary 2.8–3 × 1 mm, densely villous; style 8–9 mm long, curved in upper third, glabrous. Legumes 2.8–3.5 × 0.5–0.6 cm, oblong, puberulent and sparsely setulose-viscous, brown. Seeds 5–8, 5–6 × 3.4–3.5 mm, oblong, blackened.

Geographical distribution and habitat:— Chamaecrista carobinha is a Brazilian very common in the state of Bahia, less frequent in Piauí and now first referenced to Minas Gerais (Fig. 38 A). It lives on the edges of caatingas or thin savannas on sandy latosols, in preserved or anthropic environments, including the margins of roads and highways, between 400 and 800 meters of altitude .

Flowering and fruiting:—Species registered with flowers from February to September, with its most intense flowering from July onwards.

Conservation status: —Its estimated Range of Occurrence around 200,000 km 2 allowed us to consider the species as Least Concern (LC). However, the species is usually found in anthropized areas such as roadsides, which concerns its conservation.

Taxonomic history:— Cassia carobinha was described by Irwin & Barneby in 1978 based on the collection of “ A. Löfgren 891 ” from Bahia and transferred to the Chamaecrista genus by the same authors in 1982.

Characterization and morphological relationships: — Chamaecrista carobinha , Ch. fagonioides and Ch. hispidula have decumbent, creeping or prostrate growth, which makes them often confused and mistakenly identified in herborized collections, especially with Ch. fagonioides which it also resembles by the terminal racemes and the leaflets with revolute margins. However, Ch. carobinha can be safely distinguished from Ch. fagonioides by puberulent and non-viscous branches with sparse or absent glandular trichomes; slightly discolored leaflets and yellow petals. While Ch. fagonioides has setulose-viscous and puberulent branches; concolor leaflets and orange or reddish petals. In addition to having prostrate growth, Ch. carobinha usually has inflorescences with flowers all oriented to the same side, and its inflorescences can reach up to 60 cm long, while Ch. fagonioides is decumbent the flowers are arranged spirally in the inflorescence measuring between 2–30 cm long.

Specimens examined:— BRAZIL. BAHIA: Barreiras, BR-242, km 989, Brasília-Fortaleza, beira de estrada, 29 September 1978, (fl., fr.), L . Coradin et al. 1180 ( CEN, EAC); Brotas de Macaúbas, estrada Ibotirama – Lençóis (BR-242) Km 125, 12°25’00”S, 42°22’00”W, 09 September 1992, (fl.), L . Coradin et al. 8530 ( CEN); Caetité , cerca de 7 km de Caetité em direção a Paramirim, 14°00’12”S, 42°28’44”W, 15 July 2001, (fl., fr.), V. C . Souza et al. 26075 ( ESA); ib., Estrada de Caetité para Licínio de Almeida , BA-156, 14°19’43.2”S, 42°32’31.6”W, 1027m, 01 August 2017, (fl., fr.), A. O . Souza 2188, 2189, 2190, 2191 ( UB, UFG); Ibitiara , ca. 40 km W do entroncamento de Seabra, na BR 242 , 12°27’00’’S, 42°09’00’’W, 23 July 1993, (fl.), L. P . Queiroz et al. 3414 ( NY); Jacobina , 16 February 1986, (fl.), A . Fernandes & Matos s. n.( EAC 14056); ib., Rodovia Várzea Nova – Jacobina, 27 km de Jacobina, 11°04’41’’S, 40°43’38’’W, 794m, 24 September 2004, (fl.), E. L . Borba et al. 1945 ( HUEFS); Macaúbas, Rodovia Macaúbas a Bom Jesus da Lapa , Serra Poções, 15 June 2004, (fl.), G . Hatschbach et al. 77859 ( IBGE, SP); Morro do Chapéu , ca. 22 km W . of Morro Chapéu, 1000m, 20 February 1971, (fl.), H. S . Irwin et al. 32629 ( NY, UB); Pilão Arcado, entrada para Goiabeira do Brejo de Zacarias , 09°59’39’’S, 42°31’29’’W, 403m, 06 September 2005, (fl., fr.), L. P . Queiroz et al. 10853 ( HUEFS); Sento-Sé, 54 km de Juazeiro – Sento-Sé, 09°55’74”S, 40°97’94”W, 18 June 1985, (fl.), G . Folius 4071 ( HUEFS). Minas Gerais: Jaíba, Reserva Legal, 19 March 1998, (fl.), C. V . Mendonça et al. 417 ( UEC). Piauí: Santa Cruz , BR-316 Picos-Floriano km 27, 690m, 25 May 1980, (fl., fr.), L . Coradin et al. 2576 ( CEN) .