Spondias expeditionaria J. D. Mitch. & Daly, 2015

Mitchell, John D. & Daly, Douglas C., 2015, A revision of Spondias L. (Anacardiaceae) in the Neotropics, PhytoKeys 55, pp. 1-92 : 23

Spondias expeditionaria J. D. Mitch. & Daly sp. nov. Figs 16, 19, 21

Diagnosis.

Rare, small to medium-sized moist forest tree 8-12 m tall, with densely and shallowly fissured bark; similar to Spondias macrocarpa Engl. because of the 7-12-jugate leaves (to 16 juga in Spondias expeditionaria ), lanceolate leaflets, and long anthers (0.7-0.9 mm long), but S. expeditionaria has shorter pedicels (1.6-2.2 vs. 2.5-3.5 mm long), a taller disk (0.65-0.75 vs. (0.1) 0.3-0.6 mm tall), and the fruit (depressed-)globose vs. oblong to slightly (ob)ovoid.

Type.

BRAZIL. Espírito Santo: Mun. Aracruz, Barra do Riacho, on levee of Rio Guandú, km 22 of Baixo Guandú-Ibituba road, right side, 15 Dec 1991, D. A. Folli 1534 (holotype: CVRD!; isotypes: MO!, NY!).

Description.

Hermaphroditic trees, reproductive height 8-12 m. Trunk 36-77 cm diam.; outer bark brown, densely and shallowly fissured. Resin clear. Trichomes of three types: curved or flexuous or less often (sub)erect hairs to 0.4 (0.7) mm long; yellow to orange glandular hairs to 0.05 mm long; and (petiole and rachis only) fine bristles to 0.05 mm long. Leaves 8-16-jugate, 30-46 cm long; petiole 2.5-6.3 cm long; petiole, rachis and petiolules with dense erect to flexuous hairs, sometimes also with sparse to dense glandular hairs; lateral petiolules 0-2 mm long, the terminal one 3-27 mm long; basal leaflets 1.4-4.2 × 0.9-2.9 cm, ovate, other laterals 2.2-11 × 1.1-3.2 cm, (oblong-)(ob-)lanceolate, terminal leaflet 2.4-5 × 0.8-2.8 cm, (narrowly) elliptic; leaflet apex gradually and narrowly acuminate, the acumen 3-17 mm long; lateral lamina medially symmetrical, the base subsymmetrical or sometimes asymmetrical, slightly cordate or rarely truncate, base insertion excurrent; leaflet margin slightly revolute and sparsely and bluntly serrulate to crenate, the teeth convex-convex and the sinus shallow, the margin sometimes ciliate; leaflets membranaceous to chartaceous, both surfaces dull. Inflorescences terminal on leafy branches, 9.8-19 cm long, ca. 1.3 mm diam at base, broadly branched, the secondary axes 4.5-6.5 cm long, the axes glabrous or sometimes with sparse to scattered glandular hairs; bracts subtending inflorescences 1.5-1.6 mm long, subulate with acute apex, those subtending secondary axes 0.6-1.5 mm long, lanceolate and acuminate, some sparsely ciliate, bracteoles 0.4-0.7 mm long, ovate to lanceolate, acute to acuminate; pedicel 1.6-2.2 mm long, portion distal to articulation 1.2-1.6 mm long. Calyx 0.6 × 1.4-1.5 mm overall, aestivation apert, the lobes 0.35-0.4 mm long, triangular to lanceolate, somewhat fleshy; petals 1.8-2 × 1.1-1.2 mm, slightly obovate, apex acute to slightly acuminate, glabrous, the margin thickened, white or cream, sometimes with scattered glandular hairs, reflexed at anthesis; stamens spreading, the antesepalous and antepetalous ones 2.1-2.8 and 1.9-2.7 mm long, respectively, the anthers 0.7-0.9 mm long, in dorsiventral view broadly ovate, in lateral view oblong; disk 0.65-0.75 mm tall, 0.1-0.25 mm thick, summit craggy and outer margin crenellate; pistil ca. 1.5 mm long, subcylindrical overall, divided ca. 2/3 its length into subulate, apically slightly divergent styles 0.8-0.9 mm long, the stigmas extrorse, linear to lanceolate. Fruits 3-3.3 × 3-3.8 cm (fresh), (depressed-)globose, sometimes slightly rounded 5-costate, maturing yellowish, the surface glabrous, dull, with sparse, small, flat lenticels, the endocarp 2.9-3.2 mm diam, often 5-costate.

Leaflet venation: Fimbrial vein absent; secondary veins 7-14 pairs, spreading, the spacing and angle sometimes irregular, the angle increasing toward the base, insertion excurrent or abruptly decurrent; some perpendicular inter-secondaries present, also sometimes some perpendicular epimedial tertiaries present; intercostal tertiary veins irregular-reticulate with some admedial branching; areoles poorly developed, mostly at tertiary rank, FEVs 4+-branched, dendritic, terminating in tracheoid idioblasts; marginal ultimate venation incompletely looped; on abaxial side the midvein and secondary veins narrowly prominent, tertiaries prominulous and slightly darker than the lamina, the midvein with sparse trichomes, rest of blade with scattered trichomes of all three types; on adaxial side the midvein narrowly prominent, the secondary and tertiary veins prominulous to flat, the midvein and secondary veins with dense to sparse trichomes and sometimes scattered glandular hairs.

Distribution.

Mata Atlântica (Atlantic coastal forests) complex in the states of Minas Gerais and especially Espírito Santo, Brazil.

Ecology.

Three of the four known collections were made in pasture, a coffee plantation, and a secondary forest, so although it appears to be rare, the species is likely adapted to disturbed conditions. It has been collected in flower in Oct-Dec and in fruit in March.

Common name.

Cajá mirim (V. de Souza et al. 390, CVRD).

Etymology.

The specific epithet derives from the collecting locality of Expedicionário Alício in Minas Gerais, an appropriate name considering the obvious need for intensified botanical inventory in the region.

Specimens examined.

BRAZIL. Espírito Santo: Santa Teresa, Pedra Alegre, property of Domingos Demuner, 2 Mar 2003, Demuner 1583 (NY); Baixo Guandú, right side of Baixo Guandú-Mutum Preto road, 9 Nov 1992, Souza et al. 390 (CVRD, MO, NY). Minas Gerais: Mun. Expedicionário Alício, 16 Oct 1997, Lorenzi s.n. (NY, XLORNZI).

Conservation status.

We propose to classify this species as Critically Endangered, with the following justifications: (1) we are aware of only four herbarium collections from only two distinct localities; (2) it is evidently rare considering how few collections have been made; and (3) there is very little forest remaining in these collecting localities.

Discussion.

Spondias expeditionaria resembles Spondias macrocarpa because the leaves have numerous, usually lanceolate leaflets, excurrent leaflet base insertion, sometimes irregular spacing of secondary veins, lack of dense tufts of hairs at the leaflet bases abaxially, relatively long stamens and large anthers, the disk much taller than thick, and relatively large fruits, but the new species differs by having subsymmetric (vs. asymmetric) leaf base, the teeth convex-convex (vs. markedly concave-convex), intersecondaries (when present) perpendicular (vs. parallel); costal tertiaries irregular-reticulate with some admedial branching (vs. very little reticulation and admedially freely ramified), flower pedicel 1.6-2.2 (vs. 2.5-3.5) mm long, calyx lobes triangular (vs. ovate), petals obovate (vs. essentially elliptic), and fruit (depressed-)globose (vs. slightly ovoid to ellipsoid).

Spondias expeditionaria appears as Spondias macrocarpa in Árvores Brasileiras ( Lorenzi 1998), Brazilian Trees ( Lorenzi 2002), and Brazilian Fruits and Cultivated Exotics ( Lorenzi et al. 2006), all published before discovery of the new species. The plates show habit, bark, wood, a flowering branchlet, and mature fruits and endocarps.