Malanea evenosa Muell .Arg. ( Mueller 1875: 453, 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 evenosa Muell.Arg. ( Mueller 1875: 453, 457)

Fig. 2A-B

Type.

BRAZIL - Bahia • "partie méridionale de la prov."; 1840; Blanchet 3201a; lectotype (designated here): G [G00237735]; isolectotypes: F [F0069701F], LD [LD1817538], W [W0028441] .

Description.

Scandent shrub, 2-4 m tall; branchlets greyish brown, striated, glabrous to pubescent when young. Stipules narrow-triangular to triangular, 3.5-6 × 0.8 mm, acute, sericeous outside. Leaves with petioles 2-6(-9) mm long, pubescent to sericeous when young; blades elliptic, (2-)4-6.5 × 2-3.8 cm, obtuse to round at base, acute to acuminate at apex, margin slightly revolute, chartaceous to leathery, discolorous, glabrous above, pubescent with short golden trichomes adpressed below; secondary veins 5-6 on each side of the midrib, inconspicuous above, impressed below; tertiary veins inconspicuous on both sides; domatia hairy below. Inflorescence spiciform, 1.4-3 cm long, 1 per axil, glomerules 2-3 with 5-7 flowers each, peduncle 0.6-1.5 cm long, strigose; bracts lanceolate to narrow-elliptic, 2-2.9 mm long, externally pubescent to strigose, internally glabrous; bracteoles triangular, 0.7-0.9 mm long, pubescent. Flower buds sericeous. Calyx shallowly lobed, lobes ca 1 × 1 mm, externally puberulent. Corolla white to cream, tube 2 mm long, externally glabrous to sparse sericeous, internally lanate near the mouth; lobes acute 1.1 × 0.3-1.1 mm, externally sparsely sericeous, internally lanate. Stamens with inconspicuous filaments; anthers ca 0.6 mm long. Style ca 3 mm long. Fruits oblong, 7-8 × 4-5 mm, purple, glabrous; persistent calyx lobes glabrescent.

Distribution.

Endemic to Brazil, it occurs in Bahia, mostly in forest remnants in the Chapada Diamantina National Park and in the mountains of Minas Gerais (Fig. 1A ).

Phenology.

Flowers in May and November; fruits in March.

Etymology.

The epithet evenosa refers to the inconspicuous tertiary veins ( Müller 1875, 1881).

Preliminary IUCN conservation assessment.

Endangered (EN) B1ab(iii)+2ab(iii). The extent of occurrence (EOO) of this species was calculated as 990 km2, qualifying it for the category Endangered (EN). Its area of occupancy (AOO) was estimated as 16 km2, falling into the category Endangered (EN) ( Bachman et al. 2011; IUCN 2012, 2022). Malanea evenosa is known by six collections in only two locations in the Chapada Diamantina Nacional Park, in the central portion of the state of Bahia where the Atlantic Forest domain mixed with other domains, such as Cerrado and Caatinga, and a single location in the state of Minas Gerais. Since 1701, the economy of Chapada Diamantina region was largely dominated by mining of gold and diamonds that was responsible for the economic development and urban expansion in the area ( Giudice and Souza 2009; Giudice 2022). Only in 1985, the Brazilian government created the Chapada Diamantina National Park, aiming to preserve the natural resources and promote the tourism. Due to this, approval for all mining activities needs previous studies to measure the impacts on flora and fauna. However, currently the permitted mining exceeds the limits established by law, destroying the surrounding vegetation in the area. Therefore, we considered this species as Endangered (EN) according to IUCN criteria ( IUCN 2012, 2022).

Notes.

Müller (1875: 457) described Malanea evenosa in a brief diagnosis and cited the gatherings Blanchet 3201 and Blanchet 3201a. Five specimens of the two collections were found in F, G, LD, and W. One of them, Blanchet 3201a at G, with barcode G00237735, is designated here as the lectotype. It has handwritten notes by the author of the species, as well as leaves, buds, and fruits in good condition, which allows a correct application of the name.

Comment.

Although often misidentified as Malanea revolutifolia , M. evenosa is easily distinguished from the former by its glabrous to pubescent indumentum on young branches (vs hispid to ferruginous-tomentose), the pubescent to sericeous petiole when young (vs strigose), leaves that are acute to acuminate at the apex (vs acute, in young leaves, to rounded), margins slightly revolute (vs strongly revolute), pubescent with short golden trichomes adpressed beneath (vs tomentose to hirsute), hairy domatia in the axils of secondary veins (vs domatia absent), 5-6 secondary veins on each side of the midrib (vs 7-11), inconspicuous on the upper side (vs grooved), and calyx slightly lobed (vs deeply lobed). Few specimens of M. evenosa have been collected so far. Most of the specimens identified as M. evenosa in herbaria are, in fact, M. revolutifolia . These identifications, however, were made before the publication of M. revolutifolia .

Material examined.

BRAZIL - Bahia • Ibiquera; 13°31 ’09” S, 41°18 ’33” W; 22 Jun. 1978; fr.; Vaillant 61; RB • Palmeiras , Parque Nacional da Chapada Diamantina ; 12°27'S, 41°28"W; 1100 m; 18 Nov. 2006; fb., fl.; Cardoso 1417; HUEFS • Serra dos Lençóis, ca 2 km NE de Caeté-Açu ( Capão Grande); 12°36'S, 41°29'W; 25 May 1980; infl.; Harley 22644; HUEFS, CEPEC • Serra do Sincora , Barra da Estiva on the Capao da Volta road; 13°35'S, 41°27'W; 1300 m; 22 Mar. 1980; fr.; Harley 20710; CEPEC, K [K00015533] • s.l.; s.d.; Blanchet 3201; F [F0069701F], LD [LD1817538], W [W0028441]. - Minas Gerais • Serra do Espinhaco , 17°41 ’37” S, 43°47 ’35” W; 950-1150 m; 15 Feb. 1972; fr.; Anderson 36045; H, NY [NY00950457] , US [ US 02506579].

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 2. Species of Malanea from the Atlantic Forest. A - B. M. evenosa (Cardoso 1417). A. Lower surface of leaf with domatia. B. Inflorescence. C - F. M. forsteronioides. C. Lower surface of leaf (Hoehne 3547). D. Stipule (Furlan 1238). E. Inflorescence (Furlan 1238). F. Fruits (Bernacci 1137). G - K. M. harleyi. G. Habit (Carvalho 1364). H. Lower surface of leaf (Thomas 10378). I. Stipule (Mattos-Silva 3929). J. Inflorescence (Thomas 9494). K. Fruits (Thomas 10378). L - P. M. macrophylla. L. Habit (Silva 218). M. Lower surface of leaf (Kollmann 2109). N. Stipule (Bayman 211). O. Flower (Cardoso 1591). P. Fruits (Viana 408).