Eschweilera sphaerocarpa M. Ribeiro & S.A. Mori, 2016

Ribeiro, Michel, Mori, Scott A., Alves-Araújo, Anderson & Peixoto, Ariane L., 2016, A new species of Eschweilera (Lecythidaceae) from the Brazilian Atlantic Forest, Phytotaxa 255 (3), pp. 267-273 : 268-271

Eschweilera sphaerocarpa M. Ribeiro & S.A. Mori , sp. nov. ( Figures 1A – E & 2A – I ).

Type:― BRAZIL. Espírito Santo: Jaguaré, Estrada Jaguaré para Fátima, 18°54’50”S, 40°06’22” W, 28 December 2010, Folli 6755 (holotype CVRD! isotype NY!).

Eschweilera sphaerocarpa is characterized by its deeply fissured bark, laminate outer bark, calyx-lobes valvate and with apex irregular, and pixidium globose. It is morphologically similar to E. complanata , but can be distinguished from it by smaller leaf blades 5.8–7.4 × 2.6–5 cm (versus 9-20 × 5.5–9.5 cm), smaller flowers 2.5–3 cm diameter (versus 3–4.5 cm diameter), petals white and androecial hood light yellow (versus petals and androecial hood dark yellow), pixidium globose and seeds ellipsoid (versus pixidium depressed globose and seeds globose).

Trees, to 23 m × 45 cm dbh, without buttresses. Bark deeply fissured; the outer bark brown, laminate, thicker than inner bark; the inner bark light yellow. Leaves present at flowering, deciduous; petioles 13 – 15 × 1 – 2 mm, semicylindrical, rarely canaliculate, glabrous; blades 5.8 – 7.4 × 2.6 – 5 cm, elliptic, obovate, rarely suborbicular, coriaceous, glabrous, the base cuneate, obtuse, rarely round, margins entire to inconspicuously crenate in the upper third, slightly revolute, apex obtuse, rounded, rarely retuse; venation brochidodromous, secondary veins in 7 – 12 pairs. Inflorescences in spikes, sometimes in panicles of spikes, terminal and axillary, glabrous; rachis 3.5 – 11 cm long, lenticellate, with horizontally oriented squamulae, 8 – 12 flowers; caducous bract and bracteoles. Flowers 2.5 – 3 cm diam., glabrous, sessile; hypanthium 5 – 10 × 10 – 13 mm, campanulate, slightly angular, lenticellate, without mucilage-bearing ducts, green; calyx-lobes valvate, forming calycine rim ca. 2 mm wide, irregularly split around rim, light green; petals 4(6), 12 – 20 × 10 – 20 mm, subequal, orbicular, oblong, elliptic, cucullate, white; androecium zygomorphic, 150 – 170 stamens in staminal ring, the filaments 1.3 – 3 mm long, unequal, largest next to ligule, clavate, few sigmoid, white, the anthers 0.5 – 0.7 mm long, yellow; the hood (14 –) 20 – 24 mm diam., with single coil, light yellow, staminodes and vestigial stamens present on the interior surface of coil, vestigial stamens on the exterior surface of coil, yellow; ovary 2-locular, the ovules 5 – 10 per locule, the style oblique, poorly differentiated from summit of ovary. Pixidium 3.8 – 5 × 5.9 – 7.4 cm, globose, brown, calyx not persistent, the pericarp 11 – 20 mm thick; the infracalycine zone rounded, the supracalycine zone erect; the operculum ca. 2.7 × 4.4 cm, convex, without umbo. Seeds 1 – 3 per fruit, 2.5 – 2.7 × 1.5 – 1.8 cm, ellipsoid, circular in cross-section, reddish-brown, the veins impressed, aril basal, small.

Distribution and ecology: ―Only known from Atlantic Forest of northeastern Espírito Santo where it grows in tabuleiro forest (coastal lowland forest on Tertiary deposits). It is known only one population represented by five collections from three trees growing in a disturbed forest fragment at 82 – 90 m elev. in the municipality of Jaguaré. The Sooretama Biological Reserve and the Vale Natural Reserve represent the largest continuous area of Atlantic Forest (ca. 50,000 ha) found from north of the state of Rio de Janeiro to the south of the state of Bahia ( Garay 2003) and, located ca. 5 and 24 km from the type locality, respectively. This area possesses the greatest diversity of Lecythidaceae in the state of Espírito Santo ( Ribeiro et al. 2014). But curiously, this species has not been found in this continuous area. Collected in flower from October – December and in mature fruit with seeds in February.

Common name: ―sapucarana (Folli, D.A. 6755).

Etymology: ―the epithet refers to the shape of the fruits, an almost perfect sphere, which is different from those in other species of the section.

Additional specimens examined: ― BRAZIL. Espírito Santo: Jaguaré, Estrada Jaguaré para Fátima , 18º54’14”S 40º09’38”W, 82 m, 4 February 2010, Folli 6542 ( CVRD) ; idem, Comunidade São Jorge de Pádua , 90 m, 26 December 2013, Ribeiro, M. et al. 927 ( RB) ; Jaguaré, Comunidade São Jorge de Pádua , 18°54’28”S 40°08’46”, 90 m, 19 December 2013, Ribeiro & Costa 943 ( RB) ; Vista Alegre , 18°54’28”S 40°08’46”W, 90 m, 22 October 2014, Ribeiro & Azevedo 1136 ( RB) .

Conservation assessment: ― Eschweilera sphaerocarpa has only been collected in the municipality of Jaguaré, Espírito Santo. Based on the five known collections, its EOO and AOO are estimated to be less than 100 km ² and 10 km ² (AOO calculated in 4 km ²), respectively. The ongoing degradation of forest caused by agricultural and timber production; especially the cultivation of coffee, selective timber removal, and replacement of native forest with eucalyptus plantations impacts negatively the forest ( Fig. 2A ). This species has not yet been found in protected areas and, because of its restricted distribution, possibly E. sphaerocarpa population levels will be drastically compromised in the not too distant future. According to the IUCN (2014) criteria, the species is assigned as Critically Endangered (CR B1ab(ii)+2ab(ii)).

Figures

FIGURE 1. Eschweilera sphaerocarpa. A. Branch with flowers (based on Folli 6755). B. Flower in medial section. C. Stamens: clavate (left) and sigmoid (right) (B–C based on Ribeiro & Azevedo 1136). D. Fruit. E. Seed (D–E based on Folli 6542).

FIGURE 2. A. Tree of Eschweilera sphaerocarpa (see arrow) in a forest fragment. B. Trunk with bark deeply fissured. C. Trunk showing the outer and inner bark. (A–C Ribeiro et al. 927) D. Inflorescence. E. Details of the hypanthium and calyx. F. Flower, front view. G. Corolla with 5 and 4 petals (D–G Ribeiro & Azevedo 1136). H. Fruits. I. Fruit in tree (see arrow) (H–I Ribeiro et al. 927). Photos by M. Ribeiro, except “A” by N.P. Smith.