Rourea discolor Baker, in Martius, Fl. Bras. 14(2): 180. 1871.

Toledo, Cassio A. P., Souza, Vinicius Castro & Lucas, Eve J., 2020, Nomenclatural and taxonomic updates in Rourea subgen. Rourea sect. Multifoliolatae (Connaraceae), PhytoKeys 169, pp. 137-175 : 137

Rourea discolor Baker, in Martius, Fl. Bras. 14(2): 180. 1871. Fig. 1A

Santalodes discolor (Baker) Kuntze, Revis. Gen. Pl. 1: 155. 1891.

Eichleria lucida Progel, in Martius Fl. Bras. 12(2): 1877. Rourea progeliana Kuhlm., Arq. Inst. Biol. Veg. 1: 40. 1934. Type. Brazil. Bahia: S. d. (fl.), J. S. Blanchet 3145A (Lectotype: P barcode P 02274093!, designated by Forero 1983; isolectotypes: G!, OXF, W!).

Type.

Brazil. Bahia: Ilheos, 04 Sep 1839 (fl.), B. Luschnath s. n. (Holotype: BR barcode BR 697465!).

Description.

Lianas or scandent shrubs, 2-3 m tall; branchlets glabrous, lenticels sparse or abundant, conspicuous or inconspicuous. Leaves 9-25(-29)-foliolate, loosely disposed; petiole 1.7-4 cm long, glabrous or subglabrous, rarely sparsely villous, eglandular; rachis 6.7-12.5(-18) cm long, glabrous or subglabrous, rarely sparsely villous, eglandular; leaflets opposite to subopposite, pulvinulus 1-2 mm long; blade of the basal pair of leaflets 1.3-2.7(-3.3) × 0.8-1.6 cm, elliptic, narrowly elliptic, oblong or narrowly ovate, others 1.8-4.5(-5.8) × 0.8-1.7(-2.3) cm, narrowly elliptic, oblong or narrowly obovate, apical ones usually elliptic, chartaceous or subcoriaceous, discolorous, abaxially glabrous, sparsely puberulous, rarely pubescent, glaucous, occasionally greenish, adaxially glabrous, dull or shinning, base symmetric or slightly asymmetric, cordate, subcordate, occasionally truncate, sometimes obtuse in the apical leaflet, apex rounded, occasionally slightly obtuse, margin flat or revolute, glabrous; midvein abaxially prominent, adaxially flat, secondary veins 6-8 pairs, abaxially flat, adaxially slightly prominent, tertiary veins abaxially flat, adaxially slightly prominent. Inflorescences in axillary or pseudoterminal cymes or panicles; bracts ca. 1 mm long; peduncle 0.2-2.7 cm long, glabrous or subglabrous, eglandular; rachis 3.5-11.5 cm long, glabrous or subglabrous, eglandular; lateral branches 2.2-9.5 cm long, glabrous or subglabrous, eglandular. Flowers loosely disposed; buds 2-3 × 2-3 mm, orbicular or ovate; pedicel 6-16 mm long, eglandular, 1-2 bracteoles located up the lower half, deciduous; sepals (3.5-)4.5-5.5 × 2-2.5 mm, chartaceous, ovate, outer surface glabrous, pubescent only at the apex, eglandular, inner surface glabrous, margin glabrous or ciliate; petals (4-)6-8 × 2-2.5 mm, narrowly obovate, glabrous on both surfaces; stamens connate at base by ca. 1 mm, shorter series ca. 2.5 mm long, longer series ca. 3.5 mm long, glabrous; ovary ca. 1 mm long, densely hirsute, style ca. 1 mm long, sparsely hirsute, stigma peltate, bilobate. Fruits 1.2-1.7 × 0.4-0.6 cm, orangish or reddish, outer surface glabrous or subglabrous, sparsely hirsute only at the apex, inner surface glabrous, apex acuminate, style partially persistent or deciduous, calyx covering one third of the fruit; seeds ca. 1.3 × 0.5 cm, arillode yellowish.

Distribution, habitat and phenology.

Rourea discolor is exclusive to Bahia, where the individuals are distributed mainly in the southern coastal zone (Fig. 9 ). Its limits range from the municipality of Valença (near Itacaré) to the municipality of Porto Seguro. This is a lianescent species up to 3 m tall and occurs in dense ombrophilous, “Tabuleiro” or swamp forests, sometimes reaching areas of restinga (coastal vegetation), growing on clay or sandy soils. Specimens have been collected with flowers from August to September and with fruits from October to February.

Specimens examined.

Brazil. Bahia: Estrada que liga Serra Grande/ Itacaré, coletas a 8 km partindo da Serra Grande, 26 Aug 1992 (fl.), A. M. Amorim 671 (CEPEC, HUEFS, NY); Reserva Biológica do Mico-Leão (IBAMA), estrada no km 48 da Rod. BA-001 Ilhéus /Una, região da mata higrófila Sul Baiana, 15°09'S, 39°05'W, 18 Aug 1997 (st.), A. M. Amorim et al. 2069 (CEPEC); Jussari, RPPN Serra do Teimoso, rodovia Jussari-Palmira, estrada ca. 7.5 km de Jussari, 15°09'16"S, 39°31'52"W, A. M. Amorim et al. 4135 (CEPEC); 10 km S de Pontal ( Ilhéus), camino a Olivença, local de extraccion de arena, aprox. 14°54'S, 39°02'W, 04 Dec 1992 (fr.), M. M. Arbo et al. 5559 (SPF); Reserva Biológica de Una, estrada no km 46 da Rodovia BA-001, Ilhéus /Una, estrada principal para a sede, trilha piedade, 15°09'S, 39°05'W, 10 Sep 2006 (fl.), A. M. Amorim et al. 6274 (CEPEC, NY, SPF); Valença, estrada para Orobó, com entrada no km 3 da estrada Valença /BR 101, coletas entre o km 3-10 do ramal para Orobó, 07 Feb 1983 (fr.), A. M. de Carvalho & T. Plowan 1506 (CEPEC); Distrito de Serra Grande, 7.3 km na estrada Serra Grande/ Itacaré, Fazenda Lagoa do Conjunto Fazenda Santa Cruz, 14°25'S, 30°01'W, 11 Nov 1991 (fl.), A. M. de Carvalho et al. 3512 (ALCB, CEPEC, HUEFS, NY, US); Olivença, mata do Balneário Tararomba, 15°26'S, 39°06'W, 17 Sep 2016 (fl.), M. L. Guedes et al. 24980 (ALCB); Rod. BA-001 Ilhéus /Una ca. 50,5 km de Ilhéus, área de influência da REBIO de Una, 12 Aug 2000 (fl.), J. G. Jardim et al. 3094 (CEPEC, NY, RB); Distrito de Serra Grande, Faz. Lagoa do Conjunto e Conjunto Faz. Santa Cruz, ramal que dá acesso à sede da fazenda, ca. 300 m da rodovia, 07 Jan 2000 (fr.), F. do S. Juchum et al. 09 (CEPEC, NY); Porto Seguro, 02 Sep 1961 (fl.), A. P. Duarte 6118 (NY, RB, US); Una, Reserva Biológica da Una (REBIO da Una), estrada ca. 45 km S de Ilhéus, margem da estrada que lava à sede da reserva, 15°10'46"S, 39°03'50"W, Jan 2001 (fr.), F. do S. Juchum et al. 117 (CEPEC, NY); Rod. Una-Camandatuba, mata litorânea, solo arenoso na Faz. De Antônio Pimenta, 26 Oct 1971 (fr.), R. S. Pinheiro 1656 (CEPEC, NY); Ilhéus, Sep 1821 (fl.), L. Riedel s. n. (NY barcode NY 00393556); Serra Grande, 25 Aug 1996 (fl.), A. L. B. Sartori et al. 293 (CEPEC, UEC); 3 km north of Rodoviaria, Mata da Esperança, forest north of dam and reservoir, 14°46'55"S, 39°04'09"W, 20 Sep 1994 (fl.), W. W. Thomas et al. 10574 (MBM, NY); Uruçuca, 7.3 km north of Serra Grande on road to Itacaré, Fazenda Lagoa do Conjunto Fazenda Santa Cruz, 14°25'24"S, 39°03'38"W, 15 Nov 1995 (fr.), W. W. Thomas et al. 11015 (CEPEC).

Recognition and notes.

Rourea discolor is recognised by the glabrous or subglabrous inflorescence rachis measuring 3.5-11.5 cm long and pedicel 6-16 mm long. It is morphologically similar to R. glazioui due to the number and shape of its leaflets; however, individuals of R. discolor do not have glandular trichomes and the inflorescence rachis is glabrous or subglabrous, while in R. glazioui , they have glandular trichomes and the inflorescence rachis is hirsute or densely so. Rourea discolor can be confused with R. bahiensis as well, although they are differentiated by the characteristics of the leaflets and inflorescences (see "Recognition and notes" section of R. bahiensis ).

In the original description, Baker (1871) indicated only the specimen Luschnath s. n., without mentioning either herbarium, collector number or date. This specimen is deposited in BR and is likely to be the holotype, as no other duplicate has been found.

Rourea discolor was once treated in Oxalidaceae by Progel (1877) under Eichleria lucida . Kuhlmann (1934) proposed the combination of Eichleria in Rourea , but the basionym Rourea lucida already existed, so he named it as R. progeliana . This name is, however, a heterotypic synonym of R. discolor , as the latter had been published previously ( Baker 1871).

Figures

Figure 1. Leaves in Rourea subgen. R. sect. Multifoliolatae: A R. discolor B R. martiana C R. tenuis D R. cnestidifolia.

Figure 9. Geographic distribution of Rourea discolor.