Syagrus rupicola Noblick & Lorenzi (2010b: 41)

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

53. Syagrus rupicola Noblick & Lorenzi (2010b: 41) . Type:— BRAZIL. Goiás: Teresina de Goiás, in the region of the Chapada dos Veadeiros , on the GO-118 highway towards Alto Paraíso de Goiás —km 215 (ca. 35 km from the town of Alto Paraíso), 1,140 m, –13.87, –47.34, 7 March 2009, H. Lorenzi, R. Pimenta & R. Campos 6647 (holotype HPL!, isotypes FTG!, NY!, K!, RB!)

Figure 74 plate, Figure 65 map.

A short, robust solitary palm, slightly over 1 m tall. Stem, 10–20 cm long, short or subterranean, often appearing acaulescent. Leaves arched, with 3–6 in the crown, ca. 1 m long; sheath 17–35 cm with fibrous margins, pseudopetiole 36–55 cm long; petiole 16–30 cm long; rachis 70–120 cm long, the underside of the sheath and rachis covered by a thick white tomentum; leaflets 45–66 along each side, linear, rigid-coriaceous with apex acuminate, asymmetric, silver or bluish-green, slightly lighter on the lower surface, distributed irregularly in clusters of 2–5, inserted at different angles along the rachis, often patches of ramenta scales or tomentum present near the base along the abaxial midvein, especially where the leaflets are inserted on the rachis, basal leaflets 6–22 × 0.1–0.4 cm, middle leaflets 24–34 × 2–3 cm, apical leaflets 4.0–8.5 × 0.2–0.6 cm. Inflorescence erect, spicate to branched; prophyll 16–21 × 4.5–6.0 cm; peduncular bract covered on the exterior with a grayish indument, 56–64 cm long, expanded part 20–29 × 4–7 cm; peduncle 30–40 cm long; inflorescence axis ca. 24 cm long; rachis absent to ca. 8 cm; rachillae 1–6, ca. 9–15 cm long; staminate flowers 13.1–13.9 × 3.7–4.0 mm at the apex, 18–19 × 4.4 mm at the base, green to yellow, sepals 1.5–3.1 × 1.9–2.6 mm, glabrous, faint visible nerves, petals 11.3–12.4 mm long at the apex, 16.1 × 3.6–4.4 mm at the base with acute tips, nerves indistinct, stamens 4.4–5.4 mm long, anthers 3.0– 4.8 mm long, filaments 0.7–1.4 mm long, pistillode less than ca. 1 mm long, 0.4 mm, basal pistillate flowers pyramidal, 16–20 × 11–18 mm, glabrous, sepals 11–19 × 5.1–7.7 mm, petals 14.6–18 × 4.4–5.5 mm, upper 1/3–1/2 of petals valvate, ca. 5.8–9 mm long, glabrous, pistil 12.8–16.8 × 4.4–4.7 mm, glabrous to finely lepidote, stigmas 5 mm long, glabrous, staminodal ring ca. 1.5–2.5 mm high, 6-dentate. Fruit 3.5–3.9 × 2.5–3.4 cm, nearly globose, pale yellowish to reddish brown, epicarp covered with a fine reddish-brown lepidote indument, less than 0.5 mm thick, mesocarp thickness not measured, succulent and fibrous (pulpy), visibly splitting at the apices when mature; seed not measured, endosperm homogeneous. Germination remote-tubular.

Common name:— palmeira-da-pedra.

Etymology:— The specific epithet, rupicola , means rock dweller and alludes to the rocky habitat of this species.

Distribution and habitat:— Occurs in the northern part of the state of Goiás, Brazil, in the Chapada dos Veadeiros region, in high elevation (above 1,000 m) campo rupestre or cerrado, generally in very rocky, well-drained soils.

Conservation:— Most of the distribution of this species is contained and protected within a national park (Parque Nacional da Chapada dos Veadeiros ). The palm itself grows in very rocky places, making extraction very difficult and cultivation of such areas impossible. This species is classified as least concern, LC.

Phenology:— Fruiting in December.

Uses:— This species is a spectacular ornamental and should be successfully cultivated in rock gardens in full sun. It may grow in both tropical and subtropical regions, because it should be capable of tolerating weak freezes.

Notes:— This is a medium-sized to fairly large-sized, acaulescent to short-stemmed palm with beautiful bluish or silvery rigid-coriaceous leaves. It has large female flowers (16–20 mm long), and its fruits split at their apex, like several other rock-loving Syagrus species (i.e. S. picrophylla , S. ruschiana ).

Representative specimens:— BRAZIL. Goiás: Cavalcante, beira da estrada entre Cavalcante e Engenho II, próxima a roça do Jorge, 16 January 2010, R.C. Martins et al. 1063 (UB!); Cavalcante, Estrada entre Cavalcante e Engenho II, próxima a roça do Jorge, November 2011, R.C. Martins et al. 1145, 1148, 1149 (UB!); Cavalcante; cerca de 4 km da vila Veneno, em direção ao Rio Sã, 25 January 2001, G.P. Silva et al. 4653 (CEN); Cavalcante, Balsa do Rio Tocantins ( Serra Branca ), para Serra, 410 m, –13.57, –48.10, 23 May 2001, G.P. Silva et al. 5070 (CEN).

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 74. Syagrus rupicola. A. Habit. B. Above ground portion of the stem with persistent leaf sheaths. C. Infructescence showing the tendency of the fruit to split at their apices. D. Underside of leaflets showing the ramenta and tomentum along the rachis. E. Large old pistillate flower. Grid is in centimeters.