Syagrus procumbens Noblick & Lorenzi (2010b: 39)

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

50. Syagrus procumbens Noblick & Lorenzi (2010b: 39) . Type:— BRAZIL. Mato Grosso do Sul: Agua Clara, collected near km 107, at an entrance to a side road that gives access to a cerrado, 33 km from Agua Clara , 370 m, – 20.55, –52.58, 16 June 2008, R. Tsuji, H. Lorenzi, L.R. Noblick and R. Ventura 2677 (holotype HPL!, isotypes R!, SP!, CGMS!, UB!, CTES!, NY!, FTG!, K!, AAU!)

Figures 70–71 plates, Figure 65 map.

Short, solitary palm to less than 50 cm tall. Stem subterranean appearing acaulescent. Leaves emerging as a semicircular leaflet fan when young, later, ca. 70 m long, 2–4 in the crown, the older ones lying procumbent on the ground, only the newest leaf erect, fan-like; sheath 9–16 cm long; pseudopetiole with fibrous margins, 2–9 cm long; petiole 0–6 × 0.5 cm, 0.4 cm thick; rachis 2.5–13.0 cm long; leaflets medium to dark green (3–)5–8(–11) along each side of the rachis, linear, with long acute to acuminate, asymmetrical apex, distributed mostly regularly, arranged in one plane with the two sides forming a shallow V; no ramenta scales or tomentum present where the leaflets are inserted on the rachis and along the abaxial midvein; basal leaflets 18–55 × 0.1–0.8 cm, middle leaflets 31–78 × 0.4–1.5 cm, apical leaflets 13–59 × 0.1–1.5 cm. Inflorescence erect, spicate (rarely branched), prophyll 4.0–8.5 × 1.0– 1.5 cm; peduncular bract 6.5–20.0 cm long, expanded part 4.5–10.0 × 3.0– 4.8 cm, including a beak 0–2 mm; peduncle 7.0– 9.5 cm long; inflorescence axis 3.3–10.0 cm long; rachis absent; rachilla 1, 3.3–10.0 cm long; staminate flowers 4–13 × 4–6 mm, sepals 1–2 × 1.5–2.0 mm, petals 6–8 × 2.5–5.0 mm with acute tips, nerves indistinct, stamens 3.5–5.0 mm long, anthers 3–4 mm long, filaments 0.5–1.0 mm long; pistillate flowers elongate pyramidal, 8–19 × 4–9 mm, glabrous, sepals 8–13 × 4–9 mm, petals 9–13 × 5–8 mm, nerved, valvate tips ca. ½ to 2/3 the length of the petals, 6–7 mm long, pistil 4 × 2.0– 2.5 mm, nearly glabrous, stigmas 2–3 mm long, glabrous, staminodal ring ca. 1.5–2.0 mm high, short dentate to nearly truncate. Fruit ellipsoid, 2.5 –3.3 × 1.8–2.2 cm, yellowish tinged when mature, epicarp covered with a fine reddish brown lepidote, less than 0.5 mm thick, mesocarp ca. 3 mm thick, succulent and fibrous (pulpy); endocarp 1.5–2.6 × 1.3–1.6 cm, ca. 0.5–2.0 mm thick; seed ca. 1.1 cm in diameter with an internal cavity, endosperm homogeneous. Germination remote-tubular.

Common name:— ariri-rasteiro.

A REVISION OF THE GENUS SYAGRUS

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Etymology:— The specific epithet, procumbens , means procumbent and refers to the manner in which the lower leaves tend to lay nearly flat against the ground.

Distribution and habitat:— Goiás and Mato Grosso do Sul, Brazil, in cerrado, generally in sandy soils.

Conservation:— This small acaulescent palm is doomed to extinction in the areas of soybean production, but it is well protected within the borders of a large national park in Goiás (Parque Nacional das Emas) and within a reserve set aside by a large cellulose company near Agua Clara, Mato Grosso do Sul. Therefore, it is classified as least concern, LC.

Phenology:— Fruiting in December.

Uses:— The fruits are eaten by rodents. The plant possesses potential for cultivation in gardens.

Notes:— This is an acaulescent palm with its lower leaves lying flat or procumbent on the ground, with long narrow leaflets inserted on a relatively short rachis (2.5–13 cm). The procumbent posture of the leaves is a distinctive character, and its leaflet anatomy helps to separate if from all other acaulescent Syagrus that have spicate inflorescences ( Noblick 2013a).

Representative specimens:— BRAZIL. Goiás: Chapadão do Céu, no Parque Nacional das Emas, a beira de estrada de terra sentido Portaria do Jacuba, seguindo a partir de ponte sobre Rio Formoso , 8 June 2011, A. Campos-Rocha & H. Lorenzi 753, 761 ( HPL!) ; Mineiros, Parque Nacional das Emas , –18.08, –53.08, 10 May 1992, L.R. Noblick and H. Ferreira 4868 ( FTG!, UFG!) ; Mato Grosso: Alto Araquaia : ca. 9 km S of the city on MT-100, (a side dirt road) and 11 km S of the intersection for BR-364, ca. 748 m, –17.39, –53.25, L.R. Noblick & H. Lorenzi 5634 ( ESA!, HPL!, FTG!, NY!) ; Mato Grosso do Sul: Água Clara, em ramal da rodovia para Três Lagoas (km 10), –20.56, –52.59, 20 November 2009, H. Lorenzi 6779 ( HPL!) ; Água Clara , ca. 33 km do municipio de Água Clara (km 107), 11 December 2007, R. Tsuji s.n. ( HPL!) .

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 70. Syagrus procumbens. A. Habit. B. Underground stem. C. Leaf. D. Leaflets. E. Fruit. F. Infructescence. G. Inflorescence. H–J. Pistillate flowers. K–L. Staminate flowers. M–O. Endocarp side view, cross-section showing the interior cavity, side view, and basal end view showing the pores. A–D drawn from images taken by L. Noblick and H. Lorenzi, E–O drawn from R. Tsuji et al. 2277. All scales are in centimeters except C which is in decimeters. Drawn by Wes Jurgens.

FIGURE 71. Syagrus procumbens. A. Habit showing how the older leaves are often procumbent, laying nearly flat on the ground. B. Habit with short rachis and long pendulous leaflets. C. Habit showing the fan-like orientation of the new emerging leaf. D. Spicate inflorescence. E. Short underground stem. F. Endocarps. G. Infructescence. Scale of E is in inches and centimeters. F and G grids are in centimeters. Photos F and G are by Harri Lorenzi.