Sabinaria magnifica Galeano & R. Bernal, 2013

Galeano, Gloria & Bernal, Rodrigo, 2013, Sabinaria, a new genus of palms (Cryosophileae, Coryphoideae, Arecaceae) from the Colombia-Panama border, Phytotaxa 144 (2), pp. 27-44 : 28-42

Sabinaria magnifica Galeano & R. Bernal sp. nov.

Diagnosis. Stem solitary, 1–6 m tall, 9–12 cm diam.; leaves 20–35, induplicately palmate, with a long, basally cleft petiole; blade circular, sometimes inequilateral at base, 1.4–1.6 m diam., divided almost to the base into two large halves, these not divided again, each with 36–42 single-fold segments. Inflorescence interfoliar; peduncle at least 30 cm long; rachis 42–62 cm, with 32–40 rachillae up to 20 cm long, the basal portion of proximal rachillae bearing only pistillate flowers and deeply hidden by large rachis bracts, the distal portion and distal rachillae with staminate flowers. Staminate flowers 4–5 mm long, with 20–23 stamens. Pistillate flowers 7–11 mm long, with 14–19 staminodes that bear no anthers. Fruits closely packed, 3.6–4.4 cm long., 3–3.6 cm diam., with inconspicuous,

eccentrically apical stigmatic residue; seeds oblong-ovoid, 2.4–2.7 cm long, 2.2–2.3 cm wide, with ellipsoid hilum and subbasal ascending raphe branches; endosperm homogeneous; embryo basal ( Figs. 1–14 ).

Solitary, unarmed palm. Stem 1–6 m tall, 9–12 cm diam., light brown, smooth, with inconspicuous leaf scars. Leaves 20–35, induplicately palmate; sheath + petiole ca. 319 cm long, sheath basally cleft for ca. 43 cm, brown-woolly internally; petiole biconvex, rhomboid in transverse section, the margins sharp toward base, green, covered below with a deciduous scaly and light brown tomentum, 2 cm wide at the middle; adaxial hastula tubular, truncate, ca. 1 cm long; abaxial hastula forming a low rim; blade flat, rigid, sometimes inequilateral at base, 1.4–1.6 m diam., divided almost to the base into two large halves, these divided to ca. 1/10 their length into single fold segments, each with 36–42 single-fold segments, these free at the apex for 5–9 cm; basal segments 34–50 cm long, 1.4–1.7 cm wide, bifid at the apex for ca. 5 mm; distal segments 104 cm long, 4.2 cm wide, the free portion with a shoulder on each side just above the adaxial split, bifid at the apex for ca. 5 mm, the two tips rounded and slightly unequal, glossy above, with numerous cross-veins of two sizes, silvery-whitish below. Inflorescences and infructescences interfoliar, basally erect, the distal half arching laterally, with branches of first order or sometimes the basal branches with a few rachillae; peduncle at least 30 cm long, 1.5 cm wide at apex, subcylindrical; prophyll deeply buried among the leaves, at least 31 cm long, 3.5 cm wide, slightly two-keeled, acute and abaxially split at the fibrous apex, yellowish when fresh, covered, especially toward base, with a light brown woolly tomentum; peduncular bracts at least five, ca. 26– 27 cm long, 6 cm wide, chartaceous, persistent, acute at apex, covered with light brown, woolly, more or less persistent tomentum; rachis 46–62 cm long, subcylindrical; rachillae 32–40, each raquilla subtended by a large, persistent, chartaceous, cream-coloured bract with indumentum similar to that of the peduncular bracts, progressively smaller toward the apex, fraying into fibres in fruit; basal bracts 20–22 cm long, ca. 7 cm wide, middle bracts 13–16 cm long, 5–6 cm wide, apical bracts 4–6 cm long, 0.5–1.5 cm wide; rachillae of the proximal one half with both staminate and pistillate flowers, those of the distal half bearing only staminate flowers; basal rachillae 18–20 cm long, the proximal 1/3 thick, 5–7 mm wide, adaxially flattened and without flowers, abaxially with pistillate flowers separated from each other 1–2 mm, mostly with no anthers and only a few of them with 1–2 anthers, the distal 2/3 of proximal rachillae almost cylindrical, ca. 3 mm diam., with staminate flowers spirally arranged all around the rachilla, separated from each other 1–3 mm; middle rachillae 12–14 cm long, the proximal 2 cm similar to the corresponding area of the basal rachillae, otherwise as described for the staminate portion; apical rachillae 3–4 cm long, bearing only staminate flowers and appearing like the staminate portion of basal rachillae. Flowers whitish when fresh, borne on a short pedicel and subtended by a small, narrow triangular bract. Staminate flowers 4–5 mm long, 3–3.5 mm wide, oblong; sepals three, 1.3–2 mm long, connate into a 0.8–1 mm long cupule with three ovate long-acuminate lobes ca. 1 mm wide, fused with the corolla at a single place on the margin; corolla tubular, oblong, 2.5–3.2 mm long, the petals connate for ca. ¾ their length, with three rounded to triangular lobes ca. 1 mm wide, sometimes two of the petals completely free to base; stamens 20–23, exserted ca. 1 mm beyond the corolla; filaments connate by their fleshy bases into several irregular groups of 1–6, these in turn connate farther below with each other and basally adnate with the corolla, filiform at the apex, the free portion ca. 1 mm long, tapering to a filamentous apex ca. 0.5 mm long; anthers ca. 1 mm long, 0.2 mm wide, oblong, basally bifid, shortly bifid to rounded apically; pistillode absent. Pistillate flowers 7–11 mm long, ca. 2.5 mm wide, mostly similar to the staminate ones; sepals three, 1.3–2 mm long, connate in a 0.8–1 mm cupule with three ovate long acuminate lobes, fused with the corolla at a single place on the margin; corolla tubular, oblong, 2.5–3.5 mm long, the petals connate for ca. ¾ their length, with three rounded to triangular lobes, sometimes two of the petals completely free to base; staminodes 14–19, only slightly exserted from the corolla, filaments basally connate into a fleshy tube adnate to the corolla base, the free portion fleshy and subulate, ca. 1.5 mm long, sometimes with an apical 0.5 mm filamentous apex; anthers oblong, ca. 1 mm long, similar to those of the staminate flowers; gynoecium unicarpellate, 4–5 mm long, ovoid at the base, tapering to a slender, flattened, curved style and a papillose stigma ca. 2 mm long; ovule hemianatropous, laterally attached, bearing a large oblique aril. Fruits closely packed along the basal portion of the proximal, thickened rachilla stumps, these up to 7 cm long, 7–8 mm thick, individual fruits obovoid to turbinate or subglobose, green when immature, yellowish green when nearly mature, finally turning black, 3.6–4.4 cm long., 3–3.6 cm diam., with inconspicuous, eccentrically apical stigmatic residue; epicarp minutely tuberculate with sparse perforations, smooth with the naked eye; seeds oblong-ovoid, 2.4–2.7 cm long, 2.2–2.3 cm wide, with ellipsoid hilum and subbasal ascending raphe branches; endosperm homogeneous; embryo basal. Seedling with lanceolate eophyll, whitish below, ca. 30 cm long, 4–5 cm wide.

Type: — COLOMBIA. Chocó: Municipio de Acandí , Quebrada El Brillante, 8 km southwest of Capurganá, 130 m elev., 8°34’59.4” N, 77°23’09.9” W, 29 August 2013, G . Galeano , R. Bernal , S. Hoyos & N. Echavarría 9062 (holotype: COL; isotypes: CHOCO, FMB, JAUM, K) .

Etymology: —The Latin epithet magnifica refers to the strikingly beautiful aspect of the palm.

Habitat: —Known only from a small area at the base of the Serranía del Darién ( Fig. 15 ), in the Department of Chocó, northwestern Colombia, between 100 and 250 m elevation. The area lay less than one kilometre away from the Colombia-Panama border, and the species most probably occurs also in that country. The area is covered by premontane moist forest-warm transition (BMh-PM) in Holdridge’s life zone system ( IGAC 1977), with an average annual rainfall of ca. 3000 mm.

Common name: girasol (Spanish, =sunflower)

Uses: The leaves are used casually as umbrellas.

Additional specimens: — COLOMBIA. Chocó: Municipio Acandí, corregimiento de Capurganá, vereda El Brillante, one hour walk from Río Muerto to Capurganá, 100 m elev., 8°34’59.4” N, 77°23’09.9” W, 26 March 2013, S . Hoyos, N . López, P . Trujillo & N . Echavarría 2197 ( JAUM)

Conservation status: —There is too little information available on the distribution of Sabinaria magnifica , and a assessment of its conservation status according to IUCN parameters is therefore not possible at the present time. The area where the palm grows has extensive forests for many kilometres on both sides of the Colombia-Panama border, and the palm was locally abundant, with hundreds of adults and plants in all size categories. No major imminent threats appear to be operating in the area, although selective logging does take place, and the zone is dangerously close to the Urabá region, one of the most severely deforested areas of Colombia. Because of this, the protection of this area should be given a high priority, considering its pivotal biogeographic relevance. The establishment of public and private protected areas in this zone should be strongly encouraged.

Key to the genera of Cryosophileae

1. Perianth uniseriate........................................................ ( Coccothrinax , Hemithrinax , Leucothrinax , Thrinax , Zombia )

1. Perianth biseriate........................................................................................................................................................... 2

2. Carpel 1; leaf sheath basally cleft abaxially ................................................................................................................. 3

2. Carpels 2–4; leaf sheath cleft or not cleft ..................................................................................................................... 5

3. Flowers unisexual; pistillate flowers restricted to the lower portion of the proximal rachillae, tightly hidden by the large rachis bracts; calyx connate with the corolla at one place on its margin; two of the petals sometimes completely free; fruits closely packed and hidden among the leaf bases; leaves with a deep, medial abaxial split and no further deep splits ........................................................................................................................................................ Sabinaria

3. Flowers hermaphroditic throughout the inflorescence or at least along the proximal portion of most rachillae, and then the distal flowers staminate; flowers not hidden by rachis bracts; calyx and corolla free from each other; petals always connate; fruits neither closely packed nor hidden among the leaf bases; leaves with many deep splits in addition to a medial split ..................................................................................................................................................... 4

4. Flowers with a long, stalk-like base; proximal flowers on each rachilla hermaphroditic, distal flowers staminate; stamens 6; leaf divided to below middle into numerous single-fold segments .................................................... Schippia

4. Flowers lacking a stalk-like base, all hermaphroditic; stamens 18–24; leaf divided almost to base into 10–16 similar groups of 4–5 segments .......................................................................................................................................... Itaya

5. Stems with distinctive root spines, these often branched; stamens 6, the filaments connate in a ring; leaf sheath basally cleft abaxially .................................................................................................................................. Cryosophila

5. Stems without root spines; stamens 5–9; leaf sheath not basally cleft abaxially ......................................................... 6

6. Sepals united to approximately half their length; stamens 6, with distinct long filaments, long exserted; seed with a lobed intrusion of the seed coat; upper sheath fibres modified into stout, reflexed spines ........................... Trithrinax

6. Sepals free nearly to base, imbricate; stamens 5–9, with fleshy wide filaments, only slightly exserted; seeds lacking a conspicuous intrusion of the seed coat; sheath fibres not modified into spines .................................... Chelyocarpus

Figures

FIGURE 1. Habit of Sabinaria magnifica near Capurganá, Colombia.

FIGURE 2. Stem of Sabinaria magnifica.

FIGURE 3. Leaf base of Sabinaria magnifica.

FIGURE 4. A leaf of Sabinaria magnifica held by Angie Henao.

FIGURE 5. Leaf undersurface of Sabinaria magnifica.

FIGURE 6. Adaxial hastula of Sabinaria magnifica.

FIGURE 7. Apex of middle leaf segments of Sabinaria magnifica.

FIGURE 8. Inflorescence of Sabinaria magnifica.

FIGURE 9. Detail of staminate flowers of Sabinaria FIGURE 10. Proximal rachilla of Sabinaria magnifica showing stammagnifica. Photo by Saúl Hoyos. inate flowers (above) and pistillate flowers (below).

FIGURE 11. Details of flowers and fruits of Sabinaria magnifica. A, portion of a basal rachilla at the transition between pistillate and staminate flowers (bar = 7 mm); B, staminate flower (bar = 2 mm); C, staminate flower seen from above (bar = 2 mm); D, detail of filaments and anther of staminate flower (bar = 1 mm); E, detail of sepals fusing with petals (bar = 2 mm); F, detail of two free petals in a staminate flower (bar = 2 mm); G, pistillate flower with two anthers (bar = 2 mm); H, pistillate flower (bar = 2 mm); I, detail of staminodial tube (bar = 1 mm); J, gynoecium (bar = 1 mm); K, fruit (bar = 20 mm); L, M, seed (bar = 10 mm); N, seed in vertical section (bar = 10 mm). Drawn by Marcela Morales Sánchez.

FIGURE 12. Infructescences of Sabinaria magnifica hidden among leaf bases. Photo by Saúl Hoyos.

FIGURE 13. Fruits of Sabinaria magnifica.

FIGURE 14. Seedlings and a juvenile of Sabinaria magnifica. Photo by Saúl Hoyos.

FIGURE 15. Google Earth image showing the type locality of Sabinaria magnifica (placemark).