Malanea spicata Muell .Arg. ( Mueller 1881: 457)

Roxo, Rafaela Sales Pereira & Barbosa, Maria Regina de Vasconcellos, 2023, The genus Malanea Aubl. (Rubiaceae) in the Atlantic Forest of Brazil, Plant Ecology and Evolution 156 (3), pp. 257-275 : 257

Malanea spicata Muell.Arg. ( Mueller 1881: 457)

Fig. 4K-N

Type.

BRAZIL • Rio de Janeiro, Mauá; 8 Apr. 1875; fl., fr.; Glaziou 8166; lectotype (designated here): P [P00507166]; isolectotype: G frag. [G00074054] .

Description.

Scandent shrub ca 6 m tall; branchlets greyish brown, glabrous. Stipules obovate, 5-7 × 2.5-3 mm, acute, glabrous. Leaves with petioles 0.4-0.84 cm long, glabrous; blades elliptic-lanceolate to obovate, 8-10.4 × 3.1-4.15 cm, acute to cuneate at base, acute to cuneate at apex, margin flat, membranaceous to chartaceous, concolorous, glabrous on both sides; secondary veins 5-7 on each side of the midrib, impressed above, prominent below; tertiary veins inconspicuous. Inflorescence paniculate, 4.5-7 cm long, 1-2 per axil, glomerules (4-)5-7(-8) with 7-10 flowers each; peduncle 1.2-2.1 cm long, strigose; bracts ovate to triangular, 2.2-6.6 mm long, pubescent; bracteoles triangular, 0.1 × 0.2 mm, externally tomentose. Flower buds glabrous to glabrescent. Calyx subtruncate, ca 0.7 mm long, glabrous. Corolla white or cream, tube 1.2-1.5 mm long, externally glabrescent, internally villous; lobes rounded, 1.1-1.5 × 0.5-0.9 mm, externally glabrous to glabrescent, internally villous. Stamens with filaments ca 0.3 mm long; anthers ca 0.5 mm long. Style on short-styled flowers ca 2 mm beneath the mouth of the corolla, on long-styled flowers 3-3.5 mm long above. Fruits fusiform to ellipsoid, 5.2-6 × 3.5 mm, purple, glabrous; persistent calyx lobes tiny.

Distribution.

Previously known only from Rio de Janeiro. It is registered here for the first time in Bahia (Fig. 1D ).

Phenology.

Flowers from December to February; fruits in January, May, and August.

Etymology.

The epithet spicata refers to the spiciform inflorescence.

Preliminary IUCN conservation assessment.

Endangered (EN) B2ab(iii). The extent of occurrence (EOO) of this species was calculated as 57,711 km2, qualifying it for the category Least Concern (LC). The area of occupancy (AOO) was estimated as 28 km2, falling into the category Endangered (EN) ( Bachman et al. 2011; IUCN 2012, 2022). The species has only the type specimen collected in the state of Rio de Janeiro, in 1875. All the other eight collections are from Bahia, from only three locations in a very restricted and fragmented area in southern Bahia ( Delprete and Jardim 2019). For this reason, we consider this species as Endangered (EN).

Notes.

Müller (1881) described Malanea spicata and cited the gathering Glaziou 8166. One complete specimen of Glaziou 8166 was found in P, a fragment in G, and a photo of the destroyed specimen from B in F. Only the fragment at G has a label handwritten by Müller. Despite that, the specimen at P (P00507166) is being chosen as the lectotype because it is the only one with leaves, flower buds, and flowers in anthesis in good condition, which well characterize this species.

Comment.

Malanea spicata is frequently misidentified as M. obovata Hochr. ( Hochreutiner 1910). However, it can be distinguished by its membranaceous to chartaceous leaves that are acute to cuneate at the base (vs leathery, attenuate at the base in M. obovata ), 5-7 secondary veins on each side (vs 7-9), and the externally glabrous corolla (vs hairy). Furthermore, M. obovata occurs only in the Amazon domain, while M. spicata is endemic to the Atlantic Forest.

Material examined.

BRAZIL - Bahia • Belmonte, Estação Ecológica Gregório Bondar; 16°06 ’11” S, 39°12 ’26” W; 120 m; 8 Jan. 2002; fr.; Nunes 791; HUEFS • Belmonte, Estacao Ecologica Gregorio Bondar ; 12 Aug. 1981; fr.; Brito 57; CEPEC • Belmonte; 16°08'S, 39°15'W; 12 May 1993; fr.; Thomas 9885; CEPEC, NY [416392] • Itacaré, estrada de Itacaré para Maraú, pouco após a desembocadura do Rio de Contas ; 14°15'S, 39°00'W; 12 Dec. 2002; fr.; Fiaschi 1106; CEPEC, NY • Maraú, Rod. BR-030, trecho Porto de Campinhos-Marau , km 11; 26 Feb. 1980; fb., fl.; Carvalho 214; HUEFS, CEPEC • Maraú, mata costeira; 13 Jan. 1967; fl.; Belém 3117; CEPEC, RB • Ubaitaba-Maraú; 13 Dec. 1967; fb.; Vinha 31; CEPEC . - Rio de Janeiro • Rio de Janeiro, Mauá; 8 Apr. 1875; fr.; Glaziou 8166; RB .

Figures

Figure 1. Geographical distribution of the species of Malanea in Atlantic Forest based on georeferenced localities of herbarium specimens. A. M. evenosa (yellow circles) and M. forsteronioides (pink diamonds). B. M. macrophylla (blue circles). C. M. harleyi (turquoise diamonds) and M. martiana (orange circles). D. M. revolutifolia (red diamonds) and M. spicata (green circles).

Figure 4. Species of Malanea from the Atlantic Forest. A - E. M. martiana. A. Habit (Guedes 24971). B. Lower surface of leaf (Sant'Ana 439). C. Stipule (Guedes 24971). D. Flower (Guedes 24971). E. Fruits (Bautista 1748). F - J. M. revolutifolia. F. Habit (Popovkin 25). G. Lower surface of leaf (Ferreira 721). H. Stipule (Ferreira 721). I. Inflorescence (Ferreira 721). J. Fruits (Gusmao 469). K - N. M. spicata. K. Lower surface of leaf (Nunes 751). L. Stipule (Thomas 9885). M. Flower (Carvalho 214). N. Fruits (Fiaschi 1106).