Syagrus pompeoi Soares & Pimenta (2013a: 418)

Noblick, Larry R., 2017, A revision of the genus Syagrus (Arecaceae), Phytotaxa 294 (1), pp. 448-450 : 448-450

49. Syagrus pompeoi Soares & Pimenta (2013a: 418) . Type:— BRAZIL. Mato Grosso do Sul: Bela Vista, BR 060, 10 km [N] from the city of Bela Vista , [205 m], [coordinates redacted], 7 June 2012, K. Soares & R. Pimenta 14 (holotype HDCF [HDCF-6238])

Figure 69 plate, Figure 65 map.

Solitary palm 30–60 cm tall. STEMS subterranean, 4 cm at their base, nearly acaulescent. Leaves 3–6; sheathing leaf base ca. 4–18 × 2.6–3.5 cm with fibrous margins; pseudopetiole 3–9 cm long; petiole 1.5–8 × 0.3–0.7 cm, 0.2– 0.3 cm thick; rachis 17–50 cm long; leaflets slightly lighter on the abaxial surface, 7–15 along one side, more or less regularly arranged, inserted in more or less one plane, coriaceous to membranaceous in texture, dark green, linear, moderately covered with a waxy coating with prominently visible raised transverse veins (visible on fresh and dried material) on the adaxial surface, with whitish waxy scales or lepidote on the adaxial leaflet surface on younger leaves, whitish ramenta scales or tomentum present where the leaflets are inserted on the rachis and along the abaxial midvein; basal leaflets 8.5–43 × 0.1–0.7 cm, middle leaflets 27–57 × 0.5–1.1 cm, apical leaflets 14–35 × 0.2–0.6 cm with an asymmetric tip. Inflorescence erect, spicate or rarely branched; prophyll lanceolate, 10–13 × 1.5 cm; peduncular bract (10–) 15–26 cm long, expanded portion 7–11.5 × 2–2.8 cm, including a 0–6 cm beak, 3– 3.8 cm perimeter, 1 mm or less thickness, narrow, woody, sulcate, exterior with scattered thin indument; peduncle ca. 5–17 cm × 3–4 mm, elliptical in cross-section, tomentose; inflorescence axis 4.5–9 cm long; rachis usually absent; rachillae 1–3, glabrous, 4.5–9 cm long; staminate flowers 9–14 × 4–6 mm, yellow, sepals 1–1.5 × 1–1.6 mm, glabrous, no visible nerves, petals 9–13 × 3.3–3.5 mm with acute tips, nerves indistinct, stamens 3.5–5 mm long, anthers 3–4 mm long, filaments not measured, pistillode less than. 1 mm long; pistillate flowers pyramidal, elongate, 12–19 × 5–7 mm at the base, yellow, glabrous, sepals 12–18 × 5–10 mm, glabrous, slightly visible venation, petals 10–13 × 4–6 mm, glabrous, nerved, pistil 4–5 × 2–2.5 mm, glabrous, stigmas not measured, glabrous, staminodal ring not measured. Fruit more or less ellipsoid, 1.8–2.7 × 1.4–2.0 cm, yellow when mature, covered with a fine rusty tomentum, epicarp less than 0.5 mm thick, mesocarp, yellow, thickness not measured, succulent and fibrous; endocarp 1.4–2.5 × 0.9–1.4 cm, thickness not measured; seed ellipsoid to ovoid not measured, endosperm homogeneous. Germination remote-tubular.

Common name:— None recorded.

Etymology:— The specific epithet, pompeoi , honors the Pompeo family of Limeira, São Paulo , in particular José Pompeo Junior, a grower and collector of palms, who for a long time has supported research (i.e. Ricardo Pimenta) on the identification and conservation of native palms.

A REVISION OF THE GENUS SYAGRUS

Phytotaxa 294 (1) © 2017 Magnolia Press • 173 174 • Phytotaxa 294 (1) © 2017 Magnolia Press

NOBLICK

Distribution and habitat:— This species is known only from the type locality in Bela Vista in Mato Grosso do Sul, Brazil, where it grows in sandy, rocky soil.

Conservation:— This palm is very rare, threatened by cattle grazing, as well as by agriculture, road building and fire. After a prolonged search throughout the immediate vicinity, the author and Ricardo Pimenta were unable to locate any additional plants. With only one small location and with only a few reproductive individuals and a small number of seedlings left along the highway and in the fence line, this species is classified as critically endangered, CR B1+2ab(v); D.

Phenology:— Flowering at the end of winter (July to August) and in spring (September to November) and fruiting in summer (January to March).

Uses:— Cattle appear to readily feed on it, and it has horticultural potential.

Notes:— According to its authors, Syagrus pompeoi may be related to Syagrus procumbens by the following characters: both have a subterranean stem, similar arrangement and size of their leaves, and a spicate inflorescence. It differs from S. procumbens by its clustering vs. solitary habit, leaf rachis 33–50 vs. 2.5–20 (30) cm long, number of leaflets (8) 11–15 vs. (3) 5–8 (11), membranaceous leaflets with many visible transverse veins vs. coriaceous leaflets lacking visible transverse veins. There are also differences in the length of the peduncle, which is 10–18 vs. 7–9.5 cm in S. procumbens . The peduncular bract is only lightly covered with a sparse indument when young, while in S. procumbens it is densely covered with tomentum.

The author disagrees with the original description’s indication of a clustering habit for S. pompeoi . All the specimens observed and photographed in the wild by the author were solitary. The clustering habit is probably a misinterpretation of multiple individuals growing in close proximity with each other as was observed in S. emasensis .

Representative specimens:— BRAZIL. Mato Grosso do Sul: Bela Vista, 2008–2009, A. Campos-Rocha & R. Pimenta 614 (paratype HPL!) ; Bela Vista, N on BR-060 (exact location redacted), elevation ca. 205 m, (coordinates redacted), 24 January 2014, L.R. Noblick & R. Pimenta 5647 (paratypes ESA!, HPL!, FTG!, NY!) .

Figures

FIGURE 65. Distribution maps of Syagrus pimentae, pleioclada, S. pleiocladoides, S. pompeoi, S. procumbens, S. pseudococos, S. romanzoffiana, S. rupicola, and S. ruschiana.

FIGURE 69. Syagrus pompeoi. A. Habit. B. Ramenta on abaxial side of leaflets. C. White waxy lepidote scales on abaxial side of young leaves. D. Raised cross-veins on adaxial side of leaf. E. Habit with new emerging spathe or peduncular bract. F. Inflorescence and infructescence. G. Inflorescence. H. Inflorescence with a new emerging inflorescence and one with a few pistillate flowers in habitat.