Taxonomic revision of Chamaecrista sect. Absus subsect. Absus (Leguminosae, Caesalpinioideae) with adjustments in the new classification Author Souza, Alessandro Oliveira De 0000-0002-7057-3942 Programa de Pós-Graduação em Botânica, Instituto de Ciências Biológicas, Universidade de Brasília, Asa Norte, 70.919 - 970, Brasília, DF, Brazil. & alessandro 341 @ hotmail. com; https: // orcid. org / 0000 - 0002 - 7057 - 3942 alessandro341@hotmail.com Author Cavalcante, Raphael Guarda 0000-0001-7556-7819 Instituto de Ciências Naturais, Universidade Federal de Alfenas, 37130 - 001, Alfenas, MG, Brazil. & raphael. cavalcante @ sou. unifal-mg. edu. br; https: // orcid. org / 0000 - 0001 - 7556 - 7819 raphael.cavalcante@sou.unifal-mg.edu.br Author Silva, Marcos José Da 0000-0001-9717-5701 Programa de Pós-Graduação em Botânica, Instituto de Ciências Biológicas, Universidade de Brasília, Asa Norte, 70.919 - 970, Brasília, DF, Brazil. & Instituto de Ciências Biológicas, Departamento de Biologia Geral, Universidade Federal de Goiás, CP 131, 74001 - 970, Goiânia, GO, Brazil & Programa de Pós-Graduação em Botânica, Instituto de Ciências Biológicas, Universidade de Brasília, Asa Norte, 70.919 - 970, Brasília, DF, Brazil. & marcos _ agrorural @ hotmail. com; https: // orcid. org / 0000 - 0001 - 9717 - 5701 * Author for correspondence & Programa de Pós-Graduação em Botânica, Instituto de Ciências Biológicas, Universidade de Brasília, Asa Norte, 70.919 - 970, Brasília, DF, Brazil. marcos_agrorural@hotmail.com text Phytotaxa 2022 2022-09-20 565 1 1 82 journal article 10.11646/phytotaxa.565.1.1 1179-3163 7095806 15. Chamaecrista major (Bentham) Souza & Silva comb. & stat. nov. Chamaecrista viscosa var. major (Bentham) Irwin & Barneby (1982: 661) Cassia viscosa var. major Bentham (1870: 132) . Type :— BRAZIL . Minas Gerais : near Formigas [= Montes Claros, near 17° S , 44° W ] ”, 01 June 1840 , (fl.), Gardner 4535 ( lectotype K000555610 ! Designed by Irwin & Barneby (1978: 262) , isolectotypes BM000793278!, G00370968!). (Figs. 29 and 30) = Cassia cuneifolia Vogel (1837: 51) . nom. nud . = Cassia viscosopilosa Steudel (1843: 760) . Type :— SURINAME . s. loc ., August 1842 , (fl.), W.R. Hostmann & A . Kappler 1185 ( holotype MO-714977!, isotypes G00370971 !, G00370974 !, NY00003974 !, P00836160 !, P00836161 !, S-R-8875!, TUB009711 !, U0003210 !) . = Cassia trachyclada Glaziou (1906: 168) . Type :— BRAZIL . Entre Santa Maria et Panga, Goyaz ”, s. dat .,(fl.), A . F . M . Glaziou 20967 (holotypeK000839038!, isotypes BR0000013455125 !, F0057704 F !, G00370965 !, MPU023786 !, MPU023785 !, NY00978732 !, S- R-8873!, US 00197459!) . = Cassia viscosa var. acuta Ducke (1922: 116) . – Type: BRAZIL . in arenosis prope Gurupa, [Para] ”, 13 August 1918 , (fl.), A . Ducke 17199 ( holotype RB00539512 !, isotypes BM000793279 !, G00370966 !, US 00001721!) . Subshrubs or shrubs perennial, 0.8–2 m tall, single-stemmed, erect and branched distally. Root nodules absent. Branches, brown when mature and green when young, both setulose-viscous and puberulent, including stipules, petiole and rachis; non-exfoliating bark. Stipules 1–2.5 × 0.4–0.5 mm , lanceolate, persistent.Leaves alternate-spiral, evenly distributed on the stem, plagiotropic; petiole 5–22 mm long; rachis 5–13 mm long; leaflets 2 pairs, 0.8–2.5 × 0.5–2 cm , distal pair slightly larger than proximal pair, obcordate, spatulate or obtriangular, less often oboval or elliptical-oboval, apex emarginate or cordate and mucronate, asymmetrical base on the distal pair and cuneate on the proximal pair, papyraceous, concolorous, dark green or opaque, puberulent and sparsely setulose-viscous on both sides, margin entire, revolute, ciliated; secondary veins 3–4 pairs, conspicuous and imprinted on both sides. Leafy appendix inter-petiolule absent. Racemes 5–15 cm long, peduncle 0.4–2.5 cm long, 4–15 flowers, lax, terminal and mostly axillary, erect with straight or curved axis, setulose-viscous and villosule, including pedicel, external face of the bracts, bracteoles and sepals. Bracts 1.5–2 × 0.5 mm , oval-lanceolate, persistent. Bracteoles 1–1.2 × 0.5 mm , lanceolate, persistent. Buds 4–8 × 3.5–4 mm , globoid, ovoid or ellipsoid, apex obtuse, acute or apiculate. Flowers 2–2.2 × 1.3–1.7 cm ; pedicel 1–1.4 cm long, straight even when fruited; sepals 7–8 × 2.5–4 mm , oblong-elliptic, apex obtuse, yellow-green or yellowreddish externally; 4 flat, oboval or oblong-oboval petals and 1 falcate-curled inner petal, 11–15 × 6–8 mm , yellow; stamens 10, 3–4 mm long, anthers not barbulate; ovary 2.5–3 × 0.8 mm , setulose and villous; style 1–1.1 cm long, slightly curved in the upper third, glabrous. Legumes 2–2.5 × 0.6–0.7 cm , oblong, setulose-viscous and puberulent, light brown or greenish. Seeds 4–5, 5–5.5 × 5–5.5 mm , oblong or obovoid, blackish. Etymology: —the epithet “ major ” meaning greater or large, alludes to the height that the species can reach. Geographical distribution and habitat :— Chamaecrista major it has a distribution mainly in the northern and northeastern portion of Brazil , but extends to Bolivia, Venezuela, Guyana and Suriname (Fig. 39 B ). In Brazil , it occurs in the states of Amazonas , Bahia , Ceará , Maranhão , Minas Gerais , Pará , Piauí , Roraima and Tocantins . It grows in areas of caatinga, cerrado, edges of riparian forests and flooded areas or near water courses between 40–900 m altitude . FIGURE . Chamaecrista major . A. Habit, B–D. Fertile branches, E. Leaves, F. Inflorescences, G and H. Flowers, I. Fruit. Photographs by A.O. Souza. FIGURE 0 . Chamaecrista major . A. Fertile branch, B. Detail of the indumentum of the branch, C. Stipule, D. Leaf, E and F. Leaflets, G. Detail of the abaxial face of the leaflet, H. Bud, I. Flower, J. Sepal, K. Petals, L. Stamen, M. Gynoecium, N. Fruit. Drawned by Renato Galhardo. Flowering and fruiting :—species recorded with flowers and fruits throughout the year, both being more common between April and September. Conservation status: As it is distributed in four countries, has an Occurrence Extension greater than 400,000 km 2 , Ch. major has here its conservation framed in the Least Concern ( LC ) category. The species also forms populations with numerous mature individuals (more than 30) and occurs in areas protected by laws, such as the Uruçui-Uma Ecology Station , in Piauí , and the Grande Sertão Veredas National Park , in Bahia , and in, Minas Gerais . Taxonomic history and adjustments :— Cassia viscosa var. major was described by Bentham in 1870, admitted under the same concept by Irwin & Barneby in 1978 and transferred to the genus Chamaecrista (= Ch. viscosa var. major ) in 1982 by the same authors. Morphologically, for the previously cited authors, Ch. viscosa var. major was the only variety with a stem with distally branched secondary branches, similar in size laterally and reaching the same height as the main one, which gives it a “paniculate” or “thyrsiform” aspect of growth, and leaves with minute leaflets (0.8–2. 5 cm long) along the entire stem, characters rarely observed in the other varieties of the species. According to Irwin & Barneby (1982) the distribution of Ch. viscosa var. major differed from the other varieties, as it mainly related to the northnortheast portion of South America ( Venezuela , Suriname , Guyana , and the north and northeast of Brazil ), while the distribution of Ch. viscosa var. viscosa covered northeastern and southeastern Mexico , Colombia and western Venezuela , and that of Ch. viscosa var. paraguayensis comprised the Midwest and Southeast portion of Brazil , Bolivia , Paraguay and northern Argentina . During this study, we also found that populations of Ch. viscosa var. viscosa and Ch. viscosa var. paraguayensis overlaps in Colombia , Bolivia , southern Paraguay and northern Mexico and do not differ morphologically from each other, although they are quite different when compared to Ch. viscosa var. major . Based on phylogenetic inferences demonstrated by Souza et al. (2021) , in the peculiar morphology, above all, in the aspect of growth and leaves of Ch. viscosa var. major and its allopatric distribution, we decided to rank it to species status (= Ch. major (Benth.) A.O. Souza & M.J. Silva ) and not admit any variety for Ch. viscosa , as explained in its comments. Cassia cuneifolia by Vogel (1837) , C. viscosopilosa by Steud. (1843), C. trachyclada de Glaziou (1906) and C. viscosa var. acuta de Ducke (1922) interpreted as synonyms of Ch. viscosa var. major by Irwin & Barneby (1978) are also maintained here. Characterization and morphological relationships:Chamaecrista major resembles Ch. viscosa by congested inflorescences along the leaf axils. However, the peculiar distribution and growth aspect, as well as the leaves of similar size throughout the stem with leaflets predominantly obcordate, spatulate or obtriangular, less frequently oboval or elliptical with an always revolute margin of Ch. major separates her from Ch. viscosa which is a subshrub or shrub with growth different from that of Ch. major , with leaves at the base of the branches larger than those at the apex of these with leaflets, generally elliptical, oboval, largely elliptical or suborbicular, usually larger than those of Ch. major ; and has distribution in Central America and the western region of South America ( Bolivia , Paraguay , to the Midwest region of Brazil ). The shape, texture, indumentum and aspect of the leaflet margin of Ch. major makes it also similar to Ch. chapadae . However, Ch. chapadae is a cespitose subshrub with a maximum height of 50 cm , it has only terminal racemes and is endemic to Chapada Diamantina in Bahia . Specimens examined :— BRAZIL . Amazonas : Nhamundá , margem esquerda do rio Nhamundá , 08 July 1975 , (fl., fr.), S . Assumpção e D. Coelho 76 ( INPA ). Bahia : Baianópolis , rodovia Baianópolis-Santana km 69, 12º50’S , 44º14’W , 01 September 1994 , (fr.), G . P . Silva et al. 2515 ( CEN ); Barreiras , near Rio Piau , ca. 150 km SW. Of Barreiras , 850m , 14 April 1966 , (fl.), H . S . Irwin et al. 14800 ( L / WAG , UB ); Serra 34 km W of Barreiras , 710m , 02 March 1972 , (fl.), W . R . Anderson et al. 36444 ( NY , UB ); ib ., cerrado no entorno da Cachoeira do Acaba Vidas , 11°53’09’’S , 45°35’48’’W , 720m , 01 May 2009 , (fl.), L . P . Queiroz et al. 14438 ( HUEFS ); Correntina , BR-020 divisa Goiás-Bahia , Mimoso do Oeste km 84, 13°20’00’’S , 46°01’00’’W , 860m , 08 July 1993 , (fr.), G . P . Silva et al. 1360 ( CEN ); Formosa do Rio Preto , Fazenda escalvado, 15 May 1982 , (fl., fr.), A . Fernandes & Matos s. n. ( EAC 11327); ib ., estrada para Mateiros ( TO ), BA-458, 18 July 2017 , (fl., fr.), A . O . Souza & L . L . C . Antunes 2146 ( UB ); São Desiderio , Roda Velha , 10 March 1979 , (fl.), G . Hatschbach 42060 ( INPA , XAL ); ib ., Br-020, proximidades, do posto de gasolina de Roda Velha , 12º50’S , 45º58’W , 15 June 1983 , (fl., fr.), L . Coradin et al. 5713 ( CEN ); ib ., BR-463 de São Desiderio em direção a Sítio Grande , 12°24’46.3”S , 45°01’52.4”W , 663m , 14 May 2017 , (fl., fr.), A . O . Souza et al. 2092, 2093, 2094 ( UB , UFG ). Ceará : Crato , 20km ao N . de Crato , Sítio Barreiras de Barbalha , 22 August 1964 , (fl., fr.), A . Castellanos 25215 ( NY ). Maranhão : Carolina , perto de Carolina , 26 May 1950 , (fl.), J . M . Pires & G . A . Black 2268 ( INPA , L / U ); Caxias , 17 July 1973 , (fl., fr.), A . Fernandes s. n. ( EAC0002368 ); Coelho Neto, na estrada para Coelho Neto, perto da BR 316 , 10 June 1979 , (fl., fr.), A . J . Castro & E . Nunes s. n.( EAC0006438 ); Estreito , Rodovia Belém-Brasília , 30 km S of Estreito , J . M . Pires & M . R . Santos 16129 ( F ); Imperatriz , 08 August 1949 , (fr.), J . M . Pires & G . A . Black 1750 ( IAN ); Lajeado , entre Lajeado e Grajaú , 05 August 1978 , (fl., fr.), A . Fernandes & Matos s. n. ( EAC0004055 ); Loreto , Ilha de Balsas region , between the Rio Balsas and Parnaíba , about 15km South of Loreto , falt top pf plateau “Serra do Penitente” on trail from Faz. Trabalhosa to Lorêto , 07°12’00”S , 45°07’00”W , 08 April 192, (fl.), G . Eiten & L . T . Eiten 4205 ( SP ); Porto Franco , BR-10, km 1310- Perto de Porto Franco , 05 August 1978 , (fl., fr.), A . Fernandes & Matos s. n. ( EAC0004071 ); ib ., estrada de Porto Franco a Carolina-Maranhão , 24 April 1979 , (fl., fr.), E . P . Nunes P . Martins s. n. ( EAC0005899 ); São João dos Patos , BR-230, entre São João dos Patos e Grajaú , 23 April 1980 , (fl., fr.), A . Fernandes & E . Nunes s. n. ( EAC0008524 , HUEFS139488 ). Minas Gerais : Claro dos Poções , Rod. BR-365, 11 June 1990 , (fl.), G . G . Hatschbach 54182 ( NY ); Formoso , Parque Nacional Grande Sertão Veredas , Fazenda do Sr. Edgar , 15°09’00”S , 45°47’00”W , 31 July 1989 , (fl.), M . P . Neto 421 ( NY ); Ituiutaba, 25 km N . da cidade de Ituiutaba , 22 May 1963 , (fl.), (fl.), G . M . Magalhães 18974 ( NY ); Paracatu , Ad vias prope Paracatu , 1854, (fl.), P . W . Lund 292 ( NY ); Paraopeba , caminho do Araçaí , Horto Florestal de Paraopeba , 21 September 1955 , (fl.), E . P . Heringer 4079 ( NY , UB ); Uberlândia , Estação Ecológica do Panga , 25 September 2010 , (fl., fr.), P . K . B . Hemsing & A . R . Rezende 315 ( HUFU ). PARÁ , Gurupá , estrada do Rio Pucuruí , 18 August 1954 , (fl., fr.), J . M . Pires & N . T . Silva 4733 ( NY ); ib ., arredores do aeroporto, 07 August 1968 , (fl., fr.), M . S . Silva 1450 , 1451 ( NY ); ib ., margem da estrada Gurupá , Rio Tajapuru , 09 February 1979 , (fl.), N . T . Silva & C . Rosário 5081 ( NY ); ib ., 01°18’44”S , 51°30’54”W , November 2015 , (fl.), F . C . A . Lucas 1685 ( MFS ) Jacareacanga , Reserva Crapuri , 06°12’24”N , 57°49’28”W , August 2012 , (fl.), F . C . A . Lucas 934 ( MFS ); Monte Alegre , encosta alta da serra do Ereré , 15 May 1953 , (fl.), D. A . Lima 53-1608 ( IAN ); Óbidos , arredores do cemitério, 01 September 1968 , (fl., fr.), M . Silva 1799 ( NY ); Porto Trombetas , Areal de Terra Firme , 08 December 1993 , (fr.), S . M . Faria et al. 630 ( F ); Santarém , 10 July 1955 , (fl.), T . Alvarenga s. n. ( NY01161563 ); ib ., Cajutuba , margem direita do Rio Tapajós , 02 December 1978 , (fl.), U . N . Maciel & M . R . Cordeiro 134 ( F , NY ); ib ., rodovia Cuiabá-Santarém , 02º27’S , 54º45’W , 40m , 02 Septembrer 1984, (fl., fr.), L . Coradin et al. 7163 ( CEN ); ib ., Alter do Chão , 17 September 1998 , (fl., fr.), W . E . Magnuson s. n. ( INPA212015 ); Terra Santa , estrada que liga Porto Trombetas a Terra Santa , 03 September2009 , (fl., fr.), R . D. Ribeiro & C . G . Barbosa 1277 ( INPA ). PIAUÍ , Amarante , BR-343 Floriano-Teresina , km 40, 25 May 1980 , (fl., fr.), L . Coradin et al. 2603 ( CEN , EAC ); Barreiras do Piauí , 18 July 1981 , (fl., fr.), A . Fernandes & V . Rodrigues s. n. ( EAC 10610); ib ., APA-Estadual Fazenda Fortaleza ( Chapada das Mangabeiras ), 24 August 1996 , (fl., fr.), A . Fernandes et al. s. n. ( EAC 24260, HUEFS125213 ); Bom Jesus , Estação Ecológica de Uruçui-Una , 14 April 1981 , (fl., fr.), A . Fernandes & Del’Arco s. n. ( EAC 48819); ib ., 16 April 1981 , (fl., fr.), A . Fernandes & Del’Arco s. n. ( EAC 10026) ib ., 17 May 1984 , (fl., fr.), A . Fernandes s. n.( EAC 12582); ib ., 19 May 1984 , (fl.), A . Fernandes s. n.( EAC 12595); Currais , Rodovia PI-392, de Bom Jesus em direção a ESEC Uruçui-Una , 08°51’11.3”S , 44°49’10.3”W , 444m , 21 July 2017 , (fl., fr.), A . O . Souza & L . L . C . Antunes 2175, 2176 ( UB , UFG ); Ribeiro Gonçalves , Estação Ecológica de Uruçui-Una , 18 October 1980 , (fl., fr.), A . Fernandes & A . J . Castro s. n.( EAC9069 ); ib., 13 April 1981 , (fl.), M . R . Del’Arco s. n. ( TEPB1602 ). Roraíma : Uiramutã , cerrado ao lado do aeroporto, 04°35’46”N , 60°09’29”W , 509m , 09 November 2014 , (fl.), R . C . Forzza et al. 8291 ( NY ). Tocantins : Araguaína , ca. 5km N of Araguaína , 300 m , 14 March 1968 , (fl.), H . S . Irwin et al. 21152 ( NY , UB ); Colinas , 24 April 2005 , (fl., fr.), R . Barros 2183 ( TEPB ); Darcinópolis , rio Tocantins via fazenda do Marcelo , km 8 ( Pedra furada), 06º43’03’’S , 47º41’05’’W , 210m , 16 April 2008 , (fl.), G . Pereira-Silva et al. 12935 ( CEN ); Guaraí , 10 km ao Norte , 26 March 1976 , (fl.), G . Hatschbach 38349 ( L / WAG ); ib ., 10 km north of Guaraí along Belém-Brasília higway (BR- 153), 08°44’00”S , 48°31’00”W , 400m , 26 February 1980 , (fl.), T . Plowman et al. 9146 ( INPA , NY ); Itacajá , Reserva indígena Krahó , aldeia Pedra Branca , aproximadamente 500 m a NE da aldeia, 08°18’12”S , 47°34’56”W , 09 May 2000 , (fl.), A . A . Santos et al. 705 ( CEN ); Mateiros , Rio Novo , 10°33’00”S , 46°39’00”W , 469m , 04 May 2001 , (fl.), R . Farias et al. 437 ( CEN , UFG ); ib ., margem esquerda do rio novo, 10º33’S , 46º08’W , 400m , 08 May 2001 , (fl.), C . Proença et al. 2512 ( CEN , UFG ); Novo Acordo , Fazenda São José , margens do Córrego Funil , 216m , 05 July 2008 , (fl., fr.), E . R . Santos et al. 1641 ( HUTO ); Palmas , área do Parque Estadual do Lajeado , 10°09’13.2”S , 48°14’21”W , 16 June 2000 , (fl., fr.), E . A . Soares et al. 784 ( IBGE ); Palmeirante , folha SB-22_Z-D bacia do Tocantins , sub-bacia do rio Tocantins , 07°49’40”S , 48°01’40”W , 13 May 2010 , (fl.), F . C . A . Oliveira et al. 1971 ( ESA , IBGE ); Peixe , estrada para a praia, 30 June 2002 , (fl., fr.), R . A . Kersten & M . Borgo 574 ( FUEL ) . GUYANA . in nova Graneta , s. dat., s. col. ( L .1980011); berbice: Orealla Savannah, 1 mi. W of Orealla , Courantyne R , 04 January 1955 , (fl.), H . S . Irwin 586 ( NY ) . SURINAME . Vicinity of Saramacca river on road between Zanderiz and Tibiti river . ca. 50 km SW of Paramaribo , 12 August 1974 , (fl.), A . A . Lasseigne 4423 ( NY ) . VENEZUELA . Frontier between Territorio do Rio Branco, Brazil and Estado Bolivar , Venezuela. Along watercourse near Caju , 03 January 1955 , (fl., fr.), B . Maguire 40481 ( NY ); Bolívar : Gran Sabana ; ca. 10 km SW of Karaurin Tepui at juction of Río Karaurin and Río Asadon ( Río Sanpa ), 28 April 1988 , (fl., fr.), R . L . Liesner 24002 ( NY ) .