Desmodium polygaloides Chodat & Hassl., Bull. Herb. Boissier, Spec. Nov.
Creators: name: Lima, Laura Cristina Pires
name: Queiroz, Luciano Paganucci De
name: Tozzi, Ana Maria Goulart De Azevedo
name: Lewis, Gwilym Peter
Publisher: name: Zenodo
Year: 2014
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Fabales
Fabaceae
Desmodium
Desmodium polygaloides

description: 22. Desmodium polygaloides Chodat & Hassl., Bull. Herb. Boissier, sér. 2, 4(9): 889. 1904. Meibomia polygaloides (Chodat & Hassl.) Schindl., Repert. Spec. Nov. Regni Veg. 23: 282. 1926. Lectotype (designated here):— PARAGUAY. Yeruti: San Blas, December, E. Hassler 5782 (lectotype G00070244!, isolectotypes BM!, G00070243!). Remaining Syntypes: Paraguay. Tobaty: September, campo arenoso, E . Hassler 6272 (BM!, G!, NY!); rio Apa, campo saxoso, December, E . Hassler 8240 (BM!, G!). Fig. 24 .   
 Desmodium pachyrrhizum var. subsimplex Benth., Fl. Bras. 15(1): 101. 1859. Desmodium subsimplex (Benth.) Malme, Ark. Bot. 18(7): 11. 1922. Meibomia subsimplex (Benth.) Schindl., Repert. Spec. Nov. Regni Veg. 20: 148. 1924. Lectotype (designated here):— BRAZIL. Brasilia, F. Sellow s.n. (lectotype K000328113!, isolectotypes B!, E!, G!, K!, L!, LE![2 sheets], P!, M!, W!). Remaining syntypes: Brazil. Rio Grande do Sul: Fox s.n. (K![2 sheets]), J. Tweedie s.n. (K!).   
 Desmodium dutrae Malme, Ark. Bot. 18(7): 10. 1922. Desmodium polygaloides var. dutrae (Malme) Malme, Ark. Bot. 23(13): 29. 1931. Lectotype (designated here):— BRAZIL. Paraná: Piraguara, 7 January 1909, P. Dusén 7760 (lectotype S10- 14478!, isolectotypes BM!, E!, K!, S10-14472!). Remaining syntypes: Brazil. Paraná: Curitiba, 26 January 1904, P. Dusén 3297 (S!), Desvio Ribas, 22 February 1910, P. Dusén 9453 (K!, E!, LE!, S!); Rio Grande do Sul: Vacaria, J. Dutra 330 (BM!, S!).   
Erect, slightly branched subshrub, 0.5–2 m tall, with a xylopodium; stems not virgate, slender, cylindrical, striate, sparsely puberulous-uncinate, tomentose and hispid, not glaucous; internodes 0.5–2.5 cm long. Stipules 2–3 × 0.3–0.4 mm, narrowly triangular, not auriculate, not amplexicaul, inserted perpendicularly at the base of the leaf petiole, free from each other, apex acute, margin ciliate, glabrescent, veins conspicuous, early caducous. Leaves unifoliolate; petiole 1–5 mm long, cylindrical, sulcate, sparsely hirsute; stipels 3–7 mm long, subulate, margin straight, sparsely uncinate, persistent; leaflet concolorous, chartaceous, venation brochidodromous, primary, secondary, tertiary and quaternary veins prominent on the abaxial surface, indumentum tomentose on the primary, secondary and tertiary veins on the abaxial surface, adaxial surface glabrescent, uncinate hairs covering both surfaces, leaflet 5–14.5 × 0.3–0.8 cm, linear, base atenuate, apex obtuse or retuse, mucronate. Inflorescence a terminal pseudoraceme or paniculate; the main axis longer than the adjacent leaves, 5–20 cm long, densely hispid and uncinate, 2 flowers per node; primary bract 3–7 mm long, lanceolate, margin ciliate, sericeous on the outer surface, caducous, veins conspicuous on the outer surface; secondary bract 1–2 mm long, linear, margin ciliate,  
 DESMODIUM (LEGUMINOSAE, PAPILIONOIDEAE) IN BRAZIL   
 Phytotaxa 169 (1) © 2014 Magnolia Press • 69 sericeous on the outer surface, caducous, veins inconspicuous on the outer surface; pedicel 2–3 mm long, sparsely or densely hirsute–uncinate. Flowers 8–12 mm long; calyx bilabiate, tube campanulate, 1.5–2 mm long, pubescent and tomentose on the on the outer surface; upper lip bifid, slightly fused, the 2 teeth joined for a ca. ¾ of their length, acute, 0.1–0.3 mm long; lower lip trifid, lateral tooth lanceolate, 1.5–2.5 mm long, central tooth lanceolate, 2.5–3.5 mm long; corolla lilac, standard 9–11 × 6.5–8 mm, orbicular, apex obtuse or retuse, maculate at the base, claw 1–1.5 mm long; wing petals 11–13 × 4–4.5 mm, obovate, apex obtuse, without callosities, claw 1–1.5 mm long; keel petals 11–13 × 1.5–2.5 mm, narrowly obovate, apex subacute, with callosities, claw 2.5–3.5 mm long; androecium monadelphous, 8–12 mm long, vexillary stamen partially fused with the other from the base 3–4 mm long; ovary 3–3.5 mm long, velutinous, stipe 0.5–1 mm long, glabrescent. Loment 0.9–1.8 cm long, stipe ca. 1 mm long, glabrous, isthmus central, both margins sinuate; articles uniform 4–6, 3–5 × 2–3.5 mm, orbicular, not tortuous, indehiscent, membranaceous, veins conspicuous, densely uncinate and sericeous. Seed 2 × 1 mm, oblong, hilum subcentral.   
 Selected specimens examined:— BRAZIL. Mato Grosso do Sul: Bonito: fazenda baía das Garças, próximo a fazenda Baía das Garças, próximo a sede, direção às Cachoeiras do Aquidaban, 11 November 2002, fl., fr., V. J . Pott et al. 5970 (CGMS, HUEFS). Paraná: Guarapuava: rodovia BR-277, próximo do rio Campo Real, 22 January 1998, fl., fr., E . Barbosa et al. 106 (HUEFS, MBM). Rio Grande do Sul: Alegrete: BR 290, ca. de 43,5 leste de Alegrete, 9 December 2008, fl., fr., L. C. P . Lima et al. 460 (HUEFS); Manoel Viana: RS 176, ca. 234km Nordeste de Manoel Viana, 10 December 2008, fl., fr., L. C. P . Lima et al. 461 (HUEFS); São Gabriel: s. loc., 10 January 1969, fl., fr., A . Pott 150 (BLA, ICN). Santa Catarina: Chapecó: s. loc., 24 January 1952, fl., R . Reitz 4328 (B, PEL).   
 Distribution and Ecology:— restricted to Subtropical South America in Argentina, Brazil, Paraguay and Uruguay (Izaguirre & Beyhaut 1998, Vanni 2001, Lima et al. 2010). In Brazil D. polygaloides occurs in the States of Mato Grosso do Sul, Paraná, Santa Catarina, and Rio Grande do Sul. Collected in wet grasslands, and on foodplains.   
 Conservation Assessment:— Least Concern (LC), not endangered (IUCN 2001).   
 Phenology:— flowering and fruiting from January to October.   
 Etymology:— in a reference to the similarity of the flowers and leaves with the genus Polygala L.   
 Common Name:— pega-pega.   
 Taxonomic notes:— unifoliolate linear leaves, pseudoracemose or paniculate inflorescences, flowers 8–12 mm long, and orbicular fruit articles are characters that assist in the recognition of D. polygaloides. It is morphologically similar to D. platycarpum (see notes under that species) and D. sclerophyllum due to the linear leaflets and orbicular fruit articles, but it can be distinguished by the presence of pinkish or lilac flowers which are more than 8 mm long, a velutinous ovary, and hirsute fruit articles with conspicuous venation.   
 Among the syntypes of Desmodium polygaloides analysed, Hassler 5782, deposited in the Gherbarium (G00070244!), is designated as the lectotype as the specimen best fits the protologue.   
 Vogel (1838) described Desmodium pachyrhiza var. β based on the collection: “In Montevideo aliisque locis Brasil. Merid.; Sellow Leg.” However, he did not name this variety and therefore it is considered an invalid publication following article 34.1 of the ICBN. Bentham (1859) established Desmodium pachyrhizum var. subsimplex based on the collection cited by Vogel (1838) together with additional specimens (e.g., from Rio Grande do Sul, Fox, Tweedie, and São Paulo, Riedel).   
 Schindler (1928) commented that there was a mixture of Meibomia polygaloides and Meibomia pachyrhiza in Desmodium pachyrhizum var. subsimplex, an observation confirmed in this study through the analysis of the syntypes cited by Bentham (1859), of which “ São Paulo, Riedel 448” (K!, LE!, LECB!, and OXF!) corresponds to Desmodium pachyrhizum and the other collections: “Sellow, Fox, Tweedie” are Desmodium polygaloides.   
 As Desmodium pachyrhizum var. subsimplex was described from heterogeneous syntypes, the collection of “Sellow” deposited in K (K00328113) is here designated, in conformity with article 9.2, note 2 of the ICBN (McNeill et al. 2006), as the lectotype of this taxon as it best fits the taxon protologue.   
 Vanni (2001) considered Desmodium dutrae as a new synonym of D. polygaloides although Schindler (1928) had already made this association. Amongst the syntypes examined in our sttudy “P. Dusén 7760” (S10–14478) is selected as the lectotype because it concords best with the protologue, as well as the plate published by Malme (1922).   
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 LIMA ET AL. DESMODIUM (LEGUMINOSAE, PAPILIONOIDEAE) IN BRAZIL   
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description: Published as part of Lima, Laura Cristina Pires, Queiroz, Luciano Paganucci De, Tozzi, Ana Maria Goulart De Azevedo & Lewis, Gwilym Peter, 2014, A Taxonomic Revision of Desmodium (Leguminosae, Papilionoideae) in Brazil, pp. 1-119 in Phytotaxa 169 (1) on pages 69-71, DOI: 10.11646/phytotaxa.169.1.1, http://zenodo.org/record/10089817