Rourea cnestidifolia G. Schellenb., in Engler, Pflanzenreich IV. 127(Heft 103): 198. 1938.

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 cnestidifolia G. Schellenb., in Engler, Pflanzenreich IV. 127(Heft 103): 198. 1938. Fig. 1D

Type.

Brazil. Minas Gerais: S. d., F. Sellow s. n. (Holotype: B†). Brazil. Minas Gerais: Lagoa Santa, s. d. (fl.), J. E. B. Warming 1849 (Lectotype: K barcode K 000633716!, designated by Forero 1976).

Description.

Shrubs or scandent shrubs, 1-2.5 m tall; branchlets hirsute to glabrescent, lenticels abundant, inconspicuous. Leaves 9-13-foliolate, loosely disposed; petiole 1.9-2.8 cm long, sparsely hirsute to hirsute or sparsely villous, with glandular trichomes; rachis 4-11 cm long, sparsely hirsute to hirsute or sparsely villous, with glandular trichomes; leaflets opposite to alternate, pulvinulus ca. 1 mm long; blade of the basal pair of leaflets 2.3-4.7 × 1.3-2 cm, ovate, elliptic or oblong, others 4-7.2 × 1.6-3.2 cm, narrowly ovate, oblong or narrowly elliptic, the apical ones always elliptic or narrowly elliptic, chartaceous, slightly discolorous, abaxially hirsute or villous, occasionally subglabrous, more densely in the midvein, brownish or greenish, adaxially glabrous or subglabrous, usually sparsely villous on midvein, slightly shining or dull, base slightly asymmetric to asymmetric, usually symmetric in the apical leaflet, rounded, cordate or subcordate, occasionally acute in the apical leaflet, apex obtuse, acute or narrowly rounded, margin flat, rarely slightly revolute, ciliate or sparsely ciliate; midvein abaxially prominent or slightly prominent, adaxially impressed or slightly impressed, secondary veins 6-7 pairs, abaxially slightly prominent, adaxially flat, tertiary veins abaxially slightly prominent or flat, adaxially flat or slightly prominent. Inflorescences in axillary cymes, rarely pseudoterminal; bracts 2-3 mm long; peduncle 2.8-8 cm long, hirsute, with glandular trichomes; rachis 0.8-1.9 cm long, hirsute, with glandular trichomes. Flowers congested apically; buds 2.5-4 × 2-3 mm, orbicular or broadly elliptic; pedicel 3-5 mm long, with glandular trichomes, 2 bracteoles located up to the lower third, deciduous; sepals 4-5 × 2-2.5 mm, chartaceous, ovate, outer surface hirsute, with glandular trichomes, inner surface subglabrous or sparsely sericeous, margin ciliate; petals 7-8 × 2-3 mm, narrowly obovate or narrowly elliptic, glabrous on both surfaces; stamens connate at base by ca. 1.5 mm, shorter series ca. 1.5 mm long, longer series ca. 2.5 mm long, glabrous; ovary 1-1.3 mm long, densely hirsute, style 2-4 mm long, hirsute, stigma peltate, bilobate. Fruits 1.3-1.4 × 0.4-0.5 cm, orangish, outer surface subglabrous, sparsely hirsute at the apex, inner surface glabrous or subglabrous, apex acuminate, style partially persistent, calyx covering one third of the fruit; seeds 0.9-1 × 0.4 cm, arillode colour not seen.

Distribution, habitat and phenology.

There are only few records of this species, which seems to be restricted to central and northeastern Minas Gerais (Fig. 6 ). This shrubby species occurs in the Atlantic Forest or at the transition with the Cerrado, where it is distributed in areas of “Cerradão” and seasonal forests; it grows in rocky or limestone outcrops, at approximately 600-1,000 m altitude. Specimens have been collected with flowers from August to November and with fruits from October to December.

Specimens examined.

Brazil. Minas Gerais: Rio Doce, localidade Figueira, 11 Sep 1930 (fl.), J. G. Kuhlmann 348 (IAN, RB); Matozinhos: fazenda Cauaia, 31 Oct 1996 (fr.), J. A. Lonbardi 1453 (BHCB); Fazenda Castelo da Jagoara, 19°28'12.0"S, 43°58'59.1"W, 683 m alt., 21 Oct 2006 (fr.), J. C. F. Melo et al. 514 (BHCB, SPF). Vespasiano, região metropolitana de Belo Horizonte, afloramento calcário, adjacente à Lavra da Cia de Cimento Portland Itaú, Dec 1990 (fr.), M. A. L. Rollo 37 (SPF); Serra do Cipó, Aug 1895 (fl.), Senna s. n. (Herb. Schwacke 11747) (NY, P, RB); Lagoa Santa, s. d. (fl.), E. Warming s. n. (P).

Recognition and notes.

Rourea cnestidifolia is recognised by the presence of glandular trichomes, relatively large middle and apical leaflets (4-7.2 × 1.6-3.2 cm), obtuse, acute or narrowly-rounded leaflet apex, a long peduncle (2.8-8 cm long) and a short pedicel (3-5 mm long).

The morphological limits separating Rourea cnestidifolia and R. glazioui present slight discontinuities, but these, along with distribution patterns, are sufficient to distinguish them. They are similar in the presence of glandular trichomes on petiole, leaf rachis and inflorescences, leaflet size and shape and in overall characteristics of flowers and fruits. Schellenberg (1938) separated them based on pedicel length, while Forero (1976, 1983) used number of leaflets. These are useful distinctions despite some overlapping characters, so this revision considers that R. cnestidifolia differs from R. glazioui by the leaves 9-13-foliolate (Fig. 1D ), peduncle 2.8-8 cm long, flowers congested in the inflorescence apex and pedicel 3-5 mm long vs. leaves 13-27-foliolate (Fig. 10 ), peduncle 0.2-1.7 cm long, flowers loosely disposed in the inflorescences and pedicel 5-10(-14) mm long. Additionally, the indumentum of branchlets and leaflets (lower surface) is denser in R. glazioui than it is in R. cnestidifolia . Geographic distribution may also be useful for recognition: R. cnestidifolia is apparently restricted to central and northeast portions of Minas Gerais, while R. glazioui is very common in the coastal zone between southern Bahia and central Rio de Janeiro (Fig. 6 ).

Forero (1976) selected the lectotype of R. cnestidifolia , as the type from B is considered missing. The specimen indicated by Forero (1976) from K has no collection date, although the author cited "18 Nov 1864", probably because he considered it the same collection of specimen Warming 1849/3 from C (barcode C 10009584) and Warming 1849/1 from GH (barcode GH 00043365). However, there are, in C, many specimens Warming 1849, in which collection number is subdivided from 1 to 5 and present different collection dates. All specimens of Warming 1849 from C, GH and K seem to correspond to the same gathering, but as they do not match in collection dates and subdivision of main collection number, the lectotype from K is here considered a unicate.

Figures

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

Figure 6. Geographic distribution of Rourea cnestidifolia (circles) and R. glazioui (triangles).

Figure 10. Rourea glazioui: A fruiting branchlet B leaf, adaxial surface C inflorescence (photo by Thiago Flores) D leaf, abaxial surface.