Coccothrinax scoparia Beccari (1908: 95)

Henderson, Andrew, 2023, A revision of Coccothrinax, Hemithrinax, Leucothrinax, Thrinax, and Zombia (Arecaceae), Phytotaxa 614 (1), pp. 1-115 : 80-82

1.35. Coccothrinax scoparia Beccari (1908: 95) . Type:— HAITI. Without locality, no date, W. Buch 1908 (holotype B, destroyed). Neotype (designated here):— DOMINICAN REPUBLIC. Prov. Pedernales, near Aceitillar , port at Cabo Rojo , up Alcoa mine road (via Las Mercedes), 18°08’N 71°34’W, 1,200 m, 15 September 1981, T. Zanoni & M. Mejía 16531 (neotype JBSD!, isoneotype NY!). Plate 24

Stems 4.8(2.5–10.0) m long and 5.7(5.0–6.6) cm diameter, solitary. Leaves more or less deciduous or only leaf bases persisting on stem; leaf sheath fibers 1.3(0.8–2.7) mm diameter, stout, woody, loosely woven, ± joined or briefly free at the apices; petioles 9.1(5.5–14.2) mm diameter just below the apex; palmans 8.3(3.5–15.3) cm long, relatively short, with the adaxial veins prominent and terminating in a slight raised ridge and distinct pulvinus; leaf blades not wedge-shaped; segments 33(26–44) per leaf, the middle ones 40.3(23.5–73.0) cm long and 2.8(1.6–4.2) cm wide; segments not pendulous at the apices, giving the leaf a flat appearance; middle leaf segments tapering from base to apex, often folded, stiff and leathery, with or without scarcely developed shoulders, the apices sharply pointed and briefly splitting; middle leaf segment apices attenuate; leaf segments not waxy or sometimes with a deciduous, thin layer of wax adaxially, densely indumentose abaxially, with irregularly shaped, semi-persistent, interlocking, fimbriate hairs without an obvious center, sometimes without indumentum, scales, or wax abaxially, with well-developed transverse veinlets. Inflorescences curving, arching, or pendulous amongst the leaves, with few partial inflorescences; rachis bracts somewhat flattened, loosely sheathing, usually tomentose with a dense tuft of erect hairs at the apex; partial inflorescences 2; proximalmost rachillae straight, 4.0(2.8–6.5) cm long and 1.4(1.0–1.8) mm diameter in fruit; rachillae glabrous at or near anthesis; stamens 6–7; fruit pedicels 0.2(0.1–0.7) mm long; fruits 10.7(8.3–13.2) mm long and 10.7(9.2–13.1) mm diameter, black, blue-black, or white; fruit surfaces smooth or sometimes with projecting fibers; seed surfaces deeply lobed, the lobes running from base of seeds almost to apices.

Distribution and habitat:— Dominican Republic (Sierra Martín García and Sierra de Baoruco) and Haiti (Massif de la Hotte and probably Massif de la Selle) ( Fig. 17 ) in open pine forest, transition forest, or broadleaf forest at 1,189(667–1,603) m elevation.

Taxonomic notes:— As a preliminary species, Coccothrinax scoparia was found to be polymorphic for leaf indumentum. However, splitting the specimens into two species such that variables were consistent within each one led to improbable species that could not be justified morphologically or geographically. Otherwise, specimens have a unique combination of qualitative character states and are recognized as a phylogenetic species.

In the protologue, the type locality of Coccothrinax scoparia in Haiti was given only as “in regione sicca calcarea”. Urban (1920), for unknown reasons, reported the type locality to be “propre Ennery”, a town in northern Haiti. Beccari (1931), who must have seen the type, considered it to be from southern Haiti. Given that Buch’s later numbers were collected in southeastern Haiti ( Jiménez 1985), the type locality of C. scoparia is likely to be on or near the Massif de la Selle in southeastern Haiti. No other specimens from there are known. A specimen (Ekman 1673) was cited by Burret (1929) from the Massif de la Selle at 1,700 m, but this specimen has not been seen in the present study and is presumed destroyed (and was identified by Burret as C. montana ). There are other specimens from Haiti, but from much further west on the Massif de la Hotte. A specimen from southwestern Dominican Republic, near the Massif de la Selle, is therefore designated as neotype. Beccari (1931) described and illustrated C. scoparia as having laciniate perianth segments, but these have not been seen in the present study.

Coccothrinax scoparia is notable for its few partial inflorescences, short rachillae, and large fruits. In these it is similar to C. montana , and these two species occur at higher elevations compared to most other species of Coccothrinax . Coccothrinax scoparia differs from C. montana in its relatively short palman with the adaxial veins prominent and terminating in a slight raised ridge and distinct pulvinus. Coccothrinax scoparia also has markedly smaller leaves.

Subspecific variation:—There are five different populations of Coccothrinax scoparia (Sierra Martín García; Sierra de Baoruco, Barahona province; Sierra de Baoruco, Independencia province; Sierra de Baoruco, Pedernales province; Massif de la Hotte, Fig. 17 ). Some populations appear slightly different from others, and occur in different habitats, although in most cases there are few specimens and quantitative differences cannot be tested.

The population from the Sierra Martín García is represented by only one specimen. It occurs in the transitional zone between dry and humid forest. It is reported to have white fruits.

The population from the Sierra de Baoruco in Barahona province is represented by two or possibly three specimens. It occurs in broadleaf forest (illustrated in Fernández & Gottschalk 2017, page 149, as C. montana ). Leaves appear to lack indumentum abaxially and transverse veinlets are somewhat obscure compared to other populations. This population appears to be the same as the one mentioned by Morici & Verdecia (2006) from El Maniel, and is also said to have white fruits.

From the Sierra de Baoruco in Independencia province there are five specimens. This population occurs in broadleaf forest or pine forest, or transition forest between the two.

From the Sierra de Baoruco population in Pedernales province there are 16 specimens. This population occurs in pine forest or pine savannas on limestone soils (illustrated in Fernández & Gottschalk 2017, page 153). Fruits are recorded as blue-black or black. There are no quantitative difference between the Independencia and Pedernales populations although there are rather few data for testing.

The population from the Massif de la Hotte in Haiti is represented by five specimens. One specimen records the habitat as wet forest on jagged limestone. This population appears to have larger leaves and longer pedicels than others. It is illustrated in Fernández & Gottschalk (2017, pages 150, 151). Leaf size may be related to habitat with specimens from more open habitats having larger leaves.

It seems possible that with more data, four taxa might be recognized: Sierra Martín García; Sierra de Baoruco, Barahona province; Sierra de Baoruco, Independencia and Pedernales provinces (and probably Massif de la Selle); and Massif de la Hotte. These four are all geographically separate from one another .

Figures

FIGURE 17. Distribution of Coccothrinax samanensis, C. saxicola, C. scoparia, and C. spirituana.

PLATE 24. Coccothrinax scoparia, Dominican Republic, with leaf segments not pendulous at the apices, giving the leaf a flat appearance, the middle segments tapering from base to apex, folded, stiff and leathery, with scarcely developed shoulders, the apices sharply pointed. (Image by Eladio Fernández).