Rhynchosia diversifolia Micheli, Mém. Soc. Phys. Genève

Bezerra, Luísa Maria De Paula Alves, Cândido, Elisa Silva, Vargas, Wanderleia De, Torke, Benjamin Marland, Lewis, Gwilym Peter & Perez, Ana Paula Fortuna, 2024, Taxonomic revision of Rhynchosia Lour. (Leguminosae, Papilionoideae, Phaseoleae) in South America, Phytotaxa 643 (1), pp. 1-67 : 22-24

8. Rhynchosia diversifolia Micheli, Mém. Soc. Phys. Genève 28(7): 33. 1883.

Rhynchosia senna var. diversifolia (Micheli) Hassl. 16: 230. 1919. Type:— PARAGUAY, “Cerro Peron, près de Paraguari, dans les lieux herbeux”, January 1877 (fl./fr.), B. Balansa 1508 (Lectotype, designated inadvertently [as holotype] by Grear [1978]: G 00400127 [digital image!]; isolectotypes: P 00708500 [digital image!]; P 02748443 [digital image!]; K 000502981 [digital image!]). Iconography: Rodriguésia 70: 5. 2019. ( Fig. 6 A–C )

Rhynchosia senna Gillies ex Hook. emend. Griseb. Abh. Böhm. Ges. Wiss. 19: 122. 1874.

Rhynchosia senna var. genuina (Griseb.) Hassl. Repert. Spec. Nov. Regni Veg. 16: 230. 1919. Type : ARGENTINA, Misiones “in campis pr. San Ignacio”, s.d. (fl./fr.) Hassler 459 (Holotype: G [not seen]).

Rhynchosia senna var. diversifolia fo. genuina (Micheli) Hassl. Repert. Spec. Nov. Regni Veg. 16: 230. 1919. Type : PARAGUAY, “in pratis apricis collis Cerro-Hu”, s.d. (fl./fr.) Hassler 1223 (Lectotype, designated here: G 00379284 [digital image!]; isolectotypes: BM 000538497 [digital image!], K 000502980 [digital image!], P 00708601 [digital image!], P 02748423 [digital image!]).

Rhynchosia senna fo. glabrata (Micheli) Hassl. Spec. Nov. Regni Veg. 16: 230. 1919. Type : PARAGUAY, Santo Tomás, December 1900. E. Hassler 6492 (Holotype: G [not seen]) .

Rhynchosia diversifolia var. prostrata Burkart Fl. Prov. Buenos Aires 4(3): 628. 1967. syn. nov. Rhynchosia bicentrica B.L. Turner, Lundellia 15: 22. 2012. syn. nov. Type : ARGENTINA, Buenos Aires, “al leste de Olavarría, Sierra Barja”, December 1913 (fl./fr.), J. Najera 29 (Holotype: SI 002512 [digital image!]).

Rhynchosia edensis Izag. & Beyhaut, Leguminosas Uruguay Reg. Vecin. 1: 134–136. 1997. Type: URUGUAY, Tacuarembo, Valle Edén , November 1990 (fl./fr.), Izaguirre et al. s.n. (Holotype: MVFA 0000185 [digital image!]). syn. nov.

Subshrub prostrate to erect, stems simple to branched, pilose to pubescent, indumentum white to light yellow, with yellow vesicular glands, but lacking bulbous-based trichomes. Stipules 2–5 × 0.5–2.1 mm, free, persistent, lanceolate to triangular, externally pilose to pubescent with yellow vesicular glands, but lacking bulbous-based trichomes. Leaves trifoliolate; petiole 0.3–2.1 cm long; leaf rachis 0.4–1.3 cm long; stipels caducous; leaflets 0.5–5.2 × 0.6–2.8 cm, ovate, lanceolate, elliptical, obovate, oblong, or rounded, surface not bullate, acuminate or cuneate to rounded at apex, truncate, cuneate, subcordate, or rounded at base, margin repand to entire, pilose, with yellow vesicular glands only on the abaxial surface or on both surfaces. Inflorescences axillary, fasciculate, 1.2–2 cm long, bearing 1–7 flowers, not exceeding the length of the subtending leaf; bracts caducous; pedicel 0.3–1.2 mm long. Flowers 6–10 mm long excluding the pedicel; calyx 4–6.5 mm long, pubescent with yellow vesicular glands, but lacking bulbous-based trichomes, lobes lanceolate, not exceeding the corolla in length; standard petal 6–10 × 4–6 mm, obovate or retuse to rounded at apex, glabrous to pilose, with vesicular glands, claw 1–2 mm long, auricle ca. 0.3 mm long; wing petals 6–9 × 1–2 mm, oblong, claw 1–2.6 mm long, auricle 0.3–0.5 mm long; keel petals 6–9 × 2–3 mm, falcate, claw 2–3 mm long; stamens 6–10 mm long; ovary 2.7–3.8 mm long, pubescent, with yellow vesicular glands. Fruits 1.5–2 × 0.5–0.7 cm, brown, without constrictions between the seeds, oblong, obovate, or elliptical, pilose, with few yellow vesicular glands, but lacking bulbous-based trichomes. Seeds 1.8–3.2 × 2–3 mm, suborbicular, unicolored, brown to black.

Nomenclatural and taxonomic notes: — Hassler (1919) described the taxon R. senna var. diversifolia fo. genuina based on the collections Hassler 1223 and 2265. As the author did not designate a holotype, we designate here the Hassler collection 1223 deposited in G (barcode number 00379284) as the lectotype.

According to Burkart (1967), Rhynchosia diversifolia var. prostrata is characterized by its prostrate stems, smaller leaves than the typical variety and leaflets that are often orbicular and obtuse. Grear (1978) and Fortunato (1983) stated that this taxon is also differentiated by the arrangement of the glands on the leaflets, mentioning that in R. diversifolia var. prostrata are densely gland-dotted above and beneath and the typical variety the leaflets are not gland-dotted or sparsely above only. Turner (2012) raised R. diversifolia var. prostrata to species level, naming it R. bicentrica due to its disjunct distribution, and selecting a new species epithet because of the previous existence of R. prostrata Brandegee (1908) . However, we consider the assignment of a new name was unnecessary, because the purported diagnostic characters of R. diversifolia var. prostrata overlap with those of the typical variety. Izaguirre & Beyhaut (1997) described R. edensis , based on an unnumbered collection of Izaguirre from Uruguay. The authors mentioned that their species resembled R. diversifolia var. prostrata , but was distinguished from it by characters related to leaf size and gland arrangement; we have found these distinctions to be unreliable. For the above reasons, we here propose the synonymization of R. diversifolia var. prostrata , R. bicentrica and R. edensis under R. diversifolia .

Since we could not access the type materials of R. senna var. genuina and R. senna fo. glabrata, we keep these taxa as synonyms of R. diversifolia based on the characters described in the protologue.

Rhynchosia diversifolia can be recognized by its fasciculate axillary inflorescences ( Fig. 6 A–B ) bearing 1–7 flowers, not exceeding the length of the subtending leaf ( Fig. 6 A–C ; Bezerra et al. 2019a). It is variable in characters related to the habit, leaflet shape and size, and the arrangement of its vesicular glands, which explains misunderstandings about its circumscription and the assignment of different names by some authors. The species is similar to R. senna , a species commonly sympatric with it and with a similar disjunct distribution. The difference between the two is mainly in their leaflets, which are bigger in R. diversifolia ( Fig. 6 A–C ), and by the fruits, which are oblong, obovate, or elliptical in R. diversifolia ( Fig. 6 A ) and falcate in R. senna ( Fig. 14 K ).

Reproductive phenology: —Flowering from January to March and October to December; fruiting from January to April, July and from October to December.

Distribution and habitat: — Rhynchosia diversifolia occurs in Argentina, Bolivia, Brazil, Paraguay, Uruguay ( Fig. 7 ), northeastern Mexico and the United States. It occurs mainly in areas of the Cerrado domain, in sandy campos rupestres (rocky fields), in pastures and along roadsides.

Conservation status: — Rhynchosia diversifolia is assessed as Least Concern (LC) based on its widespread distribution in central South America and Mexico.

Selected Specimens Examined:— ARGENTINA. Buenos Aires: Arroyo e serranias de Bavard, caminho a Pigüé , 15 November 1928 (fl.), A. C. Scala s.n. ( NY) ; Lincoln , 21 December 1944 (fl./fr.), O. G. Sehulz 5698 ( NY) ; Part. Cnel. Suárez, Villa Arcadia, em cerros próximos al arroyo Sauce Corto , Balneario Los Angelitos , 13 January 1999 (fr.), G. Seijo 1395 ( MBM) . Córdoba: Dep. Colón, camino a Humaitá , via ferrea, 18 November 1976 (fl./fr.), N. Troncoso et al. 1084 ( SP) ; Dep. Punilla, 10km antes del desvio a Copina, por ruta Nac. 20, camino a altas cumbres, 31º31’S 64º37’W, 14 March 1996 (fr.), R. H. Fortunato 5330 ( MBM) ; Dep. Tercero Arriba, Tancacha, caminho de Tancacha a Rio 3º, December 1924 (fl./fr.), A. Scala s.n. ( SP) . Corrientes: Dep. Monte Caseros, Juan Peyol , 10 February 1945 (fr.), F. Ibarrola 2367 ( NY) ; Dep. Santo Tomé, Estancia Garruchos , casco, 10 February 1972 (fr.), A. Krapovickas et al. 21474 ( MBM) . San Luis: Rio de las Barranquitas , January 1934 (fl./fr.), M. A. Vignati 201 ( NY) ; Tucumán: Burruyacú , El Puestilo, 9 October 1928 (fl./fr.), S. Venturi 7357 ( NY) ; Estación Oraoz ( FECA) , 21 November 1925 (fl.), Lehreiter 3971 ( NY) . Misiones: Dep. Apóstoles, Arroyo Cuñá Maná , 6 November 1944 (fl./fr.), F. Ibarrola 1036 ( NY) ; Dep. San Ignacio , 19 December 1944 (fl.), J. E. Montes 492 ( NY) . BOLIVIA. Chuquisaca: Rosal , 3 October 1949 (fl.), Brooke 5752 ( BM) ; Vallegrande, 5.5 km S of Vallegrande, vic. Santa Rosita, Quebrada Huasa Canada , 24 December 1989 (fl./fr.), M. Nee 38346 ( NY) . BRAZIL. Paraná: Guarapuava, Faz. Campo Real , 17 November 1963 (fl.), E. Pereira & G. Hatschbach 7995 ( MBM, NY) . Rio Grande do Sul: Alegrete, Lageadinho cerca de 16 km após Alegrete em direção a Rosário , 12 February 1990 (fl./fr.), D. B. Falkenberg 5273 ( FLOR) ; ibid., parada de trem Perau , 29 October 1989 (fl./fr.)., L. A. Z. Machado 264 ( SMDB) ; ibid., Arroio dos Ratos, BR 290 km 159, 7 November 1988 (fl./fr.), M. L. Abruzzi 1554 ( HAS) ; Bagé , 1 December 1992 (fr.), N. R. Bastos s.n. ( PACA) ; BR 153m km 135, ponte sobre o Arroio Quebradinho , 2 November 1981 (fl.), O. Bueno 3306 ( HAS) ; ibid., ca. 20 km da cidade, 11 November 1995 (fl.), R. Záchia 1977 ( FLOR) ; ibid., em frente a Fazenda Santa Genoveva na estrada de Bagé para Serrilhada , 6 December 1982 (fr.), J. F. M. Valls et al. 6980 ( CEN) ; Balneario Guaruja p. Porto Alegre , 23 November 1947 (fr.), B. Rambo s.n. ( PACA) ; Butiá , 17 January 1989 (fl.), P. Brack & P. L. Oliveria 143 ( HAS) ; Caçapava do Sul, 13 December 1982 (fl./fr.), D. B. Falkenberg 21 ( FLOR, MBM) ; ibid., BR 153 entre km 488 e 489, 21 January 1994 (fl./fr.)., D. B. Falkenberg et al. 6437 ( BHCB, FLOR) ; ibid., Irapuá, Guarda Velha , January 1988 (fl./fr.), L. A. Z. Machado 30 ( SMDB) ; ibid., na rodovia para Bagé , 11 March 1982 (fl.), G. Mattos & N. Mattos 26224 ( HAS) ; ibid., Rincão de Lurdes , 4 November 1989 (fl./fr.), L. A. Z. Machado 354 ( SMDB) ; ibid., Vila Progresso, BR 290, 4 November 1989 (fr.), L. A. Z. Machado 360 ( SMDB) ; Cachoeira do Sul, no km 145 da rodovia P.Alegre - Uruguaiana , 17 October 1984 (fl./fr.), G. Mattos & N. Silveira 30782 ( HAS) ; Candiota, BR 293, em frente a Usina Presidente Médici , 2 November 1997 (fl.), E. N. Garcia & J. Jarenkow 238 ( MBM) ; Canoas, Bairro São José, Av. João Leivas de Carvalho , 31 December 2001 (fl./fr.), A. S. Flores & R. S. Rodrigues 730 ( UEC) ; Cristal, Paradouro Gril , há 158 km de PoA, 7 December 1990 (fr.), L. A. Z. Machado 656 ( SMDB) ; Dom Pedrito, Coxilha de São Sebastião, Cabanha Dois Pinheiros , December 1981 (fr.), N. Bastos s.n. ( BLA) ; ibid., km 203 da BR 293 2km a leste do primeiro acesso a ser trilado na rodovia Bagé-Dom Pedrito , 2 December 1982 (fl./fr.), J. F. M. Valls et al. 6910 ( CEN) ; ibid., porteira do Sarandi na Fazenda Santa Placida de Anibal Osorio , 3 December 1982 (fl.), J. F. M. Valls et al. 6946 ( CEN) ; Espirito Santo p. Porto Alegre , 1945 (fl./fr.), K. Emrich s.n. ( PACA) ; Estrada do Rio Grande do Sul, ca. De 10km de Quaraí na rodovia para Alegrete , 19. October 1984 (fr.), G. Mattos & N. Silveira 26122 ( HAS) ; Faz. da Ronda p. Vacaria , 11 January 1947 (fl./fr.), B. Rambo s.n. ( PACA) ; Faz. do Jarau p. Quaraí , January 1945 (fl.), B. Rambo s.n. ( PACA) ; Granja Neugebauer p. Itapoan , 3 April 1949 (fr.), B. Rambo s.n. ( PACA) ; Guabiju , 29 March 1991 (fl./fr.), L. A. Z. Machado 1344 ( SMDB) ; Guaíba, Fazenda Maximiano , 7 November 1992 (fr.), N. R. Bastos et al. s.n. ( PACA) ; ibid., na estação experimental, 17 January 1984 (fl./fr.), N. Silveira 790 ( HAS) ; Ibaré , há 13 km de Ibaré, 30 March 1991 (fl./fr.), L. A. Z. Machado 1428 ( SMDB) ; Itaqui - Sobradinho / Manoel Viana , 15 January 1991 (fr.), Machado et al. 1056 ( SMDB) ; Jarí p. Tupanceretan , 25 January 1942 (fr.), B. Rambo s.n. ( PACA) ; Lavras do Sul, Arr. Jaguarizinho , 30 March 1991 (fl./fr.), L. A. Z. Machado 1430 ( SMDB) ; ibid., Fazenda dos Ferreira, 7 December 1993 (fr.), N. R. Bastos 412 ( PACA) ; Morro Agudo p. Porto Alegre , 13 April 1949 (fr.), B. Rambo s.n. ( PACA) ; Morro da Polícia p. Porto Alegre , 8 November 1948 (fl./fr.), B. Rambo s.n. ( PACA) ; Morro do Vigia p. Livramento , 12 January 1941 (fr.), B. Rambo s.n. ( PACA) ; Passo do Socorro p. Vacaria , 26 December 1951 (fr.), B. Rambo 51497 ( MBM) ; Passo Fundo , ao leste da cidade, 29 January 1990 (fr.), A. Polking & L. A. Z. Machado 488 ( SMDB) ; Pedro Osório, Alto Alegre , 6 December 1991 (fl./fr.), L. A. Z. Machado 1598 ( SMDB) ; Pelotas, estrada para o Laranjar , 10 November 1995 (fl./fr.), R. Záchia 1946 ( SMDB) ; Pestana p. Ijuí , 26 January 1955 (fl.), Pivetta 1019 ( PACA) ; Porto Alegre, Morro da Polícia , 20 November 1992 (fl./fr.), N. R. Bastos s.n. ( PACA) ; Quaraí , 13 February 1972 (fl./fr.), Andrade-Lima 72-6844 ( IPA) ; Santana do Livramento , 3 March 2015 (fr.), G. Schlineedwein s.n. ( BLA) ; ibid., Estância São Miguel - Sarandi , November 1936 (fl./fr.), E. F. Xavier s.n. ( BLA) ; Santiago, Capão Cipó, Assentamento Santa Rita , 9 March 1989 (fl./fr.), L. A. Z. Machado 199 ( SMDB) ; Santo Angelo , 17 March 1952 (fl./fr.), B. Rambo s.n. ( PACA) ; São Francisco de Assis - Boqueirão , 16 January 1991 (fr.), Machado et al. 1215 ( SMDB) ; São Gabriel , January 1952 (fr.), J. Barreto 110 ( BLA) ; ibid., July 1970 (fr.), Valls & Pott s.n. ( BLA) ; ibid., Estação Experimental de Forrageiras , January 1952 (fl./fr.), I. L. Barreto 11 ( BLA) ; ibid., 5 March 1963 (fr.), J. Mario 28 ( BLA) ; Sanga Funda (rumo a Bagé ), 29 March 1991 (fl./fr.), L. A. Z. Machado 1372 ( SMDB) ; São Luiz Gonzaga, BR 285, de S. Luiz Gonzaga em direção a Santo Antônio das Missões , 10 January 1999 (fr.), E. Biondo s.n. ( SMDB) ; São Sepé, BR 392 próximo ao trevo Santa Maria - São gabriel, 06 November 1990 (fl./ fr.), M. L. Abruzzi 2037 ( HAS) ; Tapes, ca. 10km depois do trevo em direção a Camaquã (BR-116), 16 December 1996 (fl./fr.), J. A. Jarenkow 3330 ( FLOR, MBM) ; Tupanciretã , 28 January 1942 (fl./fr.), B. Rambo s.n. ( PACA) ; Uruguaiana, Arroio Imbaá , 18 November 1984 (fl./fr.), M. Sobral 3445 ( MBM) ; Vacaria , 6 February 1985 (fr.), N. Silveira et al. 2418 ( HAS) ; ibid., na estação experimental, 23 February 1977 (fl./fr.), G. Mattos 16712 ( HAS) ; Viamão, Estação experimental de Viamão, 13 March 1984 (fl./fr.), J. Guaranja & J. Vasconcellos 78 ( HAS) . Santa Catarina: Campos Novos, Rodovia BR 470, km 337, em frente a entrada da fazenda Bom Retiro , 12 January 2001 (fl./fr.), L. D. Rogalski 161 ( ICN) . MEXICO. Nuevo León: Sierra Madre Mts., Monterrey , 18 July 1933 (fl./fr.), C. H. Muller & M. T. Muller 501 (GH 00266851 digital image) . PARAGUAY. Guairá: Vila Rica, Serro Pelado , January 1930 (fl.), Jorgensen 4563 ( US) . UNITED STATES. Texas: rives de l’Aransato pres Goliad , May 1834 (fl./fr.), J. L. Berlandier 3131 (GH 02134195 digital image) . URUGUAY. Colonia: Carmelo, Cerros , 6 December 1934 (fl./fr.), A. L. Cabrera 3202 ( NY) . Florida: Cerro Colorado, Estancia San Pedro , December 1936 (fl./fr.), Gallinal et al. B751 ( NY) ; Montevideo, “du Cerro”, December 1839 (fl./fr.), M. A. Isabelle 24 ( NY) . Rivera, Bajada de Pena , ruta 30 km 253 31º08’33”S 55º54’54’’ W, 262 m. s.m., 26 November 2001 (fr.), G. Seijo et al. 2489 ( MBM) . Salto: Santo Antonio, Escuela de Agronomia , 2 February 1937 (fl.), B. Rosengustt 1069 ( NY) ; Tacuarembó, Valle Edén , 18 February 2005 (fl./fr.), M. Dematteis & A. Schinini 1534 ( NY) .

Figures

FIGURE 6. Rhynchosia species. A–C. R. diversifolia. D–G. R. edulis. H–I. R. erythrinoides. (A, B, E by T.C. Monteiro); (C by L.M.P.A. Bezerra); (D, F, G by D. S. Gissi) and (H, I by N. R. Marcial).

FIGURE 7. Geographical distribution of Rhynchosia diversifolia, R. edulis and R. erythrinoides in South America.

FIGURE 14. Rhynchosia species. A–C. R. phaseoloides. D. R. platyphylla. E–H. R. reticulata. I–J. R. schomburgkii. K–L. R. senna. (A, E–H, L by L. M. P.A. Bezerra), (B, C, K by T. C. Monteiro), (D by C. Martins) and (I–J by A. P. Fortuna-Perez).