Coccothrinax spissa Bailey (1939b: 253)

Henderson, Andrew, 2023, A revision of Coccothrinax, Hemithrinax, Leucothrinax, Thrinax, and Zombia (Arecaceae), Phytotaxa 614 (1), pp. 1-115 : 84

1.37. Coccothrinax spissa Bailey (1939b: 253) . Lectotype (designated by Reveal & Nixon 2013):— DOMINICAN REPUBLIC. Hispaniola, Santo Domingo, near Bani , 27 July 1939, L. Bailey 271 (lectotype BH!). Plate 26

Stems 4.9(2.5–6.5) m long and 24.2(11.0–50.0) cm diameter, solitary, often swollen. Leaves more or less deciduous or only leaf bases persisting on stem; leaf sheath fibers 0.4(0.1–0.7) mm diameter, thin, closely woven, not forming persistent ligules and soon disintegrating at the apices; petioles 16.6(11.9–26.4) mm diameter just below the apex; palmans 22.4(14.0–31.5) cm long, relatively long, without prominent adaxial veins; leaf blades not wedge-shaped; segments 60(47–71) per leaf, the middle ones 74.5(51.5–99.5) cm long and 3.3(2.5–4.4) cm wide; segments not pendulous at the apices, giving the leaf a flat appearance; middle leaf segments relatively long and narrow, tapering from base to apex, scarcely folded, flexible and not leathery, a shoulder or constriction absent or poorly developed, the apices thin, deeply splitting and breaking off; 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, with well-developed transverse veinlets. Inflorescences curving, arching, or pendulous amongst the leaves, with few to numerous partial inflorescences; rachis bracts swollen, woody, not or sparsely tomentose; partial inflorescences 5(3–6); proximalmost rachillae straight, 13.6(7.5–22.0) cm long and 1.6(0.9–2.4) mm diameter in fruit; rachillae glabrous at or near anthesis; stamens 10(9– 13); fruit pedicels 1.3(0.5–2.7) mm long; fruits 8.6(6.7–10.1) mm long and 8.6(6.5–9.9) mm diameter, purple, red-purple, white to purple, magenta, magenta to blackish; 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:— Haiti and Dominican Republic ( Fig. 18 ) in broad leaf forest or dry forest, and persisting in disturbed areas, at 243(7–675) m elevation.

Taxonomic notes:— Two preliminary species ( C. spissa , C. fragrans from Hispaniola) share a unique combination of qualitative character states and are recognized as a phylogenetic species, for which the earliest name is C. spissa . Note that the preliminary species C. fragrans refers here only to specimens from Hispaniola, which were mistakenly referred to by Bailey (1939b) as C. fragrans . Stems, leaves, and inflorescences of Coccothrinax spissa are the largest of any species in the genus, and stems may be swollen or columnar. Sometimes C. spissa is sympatric with C. argentea and it can be difficult to distinguish specimens. It seems likely that there are hybrids between the two.

Subspecific variation:— Coccothrinax spissa is widely distributed throughout Hispaniola. The population in the southern part of the Dominican Republic, which includes the type locality, occurs in a dryer habitat. Stems of this population are usually considered to be consistently swollen. However, according to the label of one specimen (Moore 7592) there is considerable variation in the amount of swelling. As shown in the image in Sayers (2012, pages 26–27), some stems are swollen and some columnar. Nevertheless, specimens from this southern population seem quite similar to one another, especially in their rachillae that dry a distinctive light brown color. One specimen (Zanoni 31093) from the southern population was determined by the collector as C. argentea and said to occur in a mixed population with C. spissa . However, Zanoni 31093 is here considered to be a depauperate plant of C. spissa .

In other areas, specimens appear much more variable. Stems within a population may be either swollen or columnar, as illustrated in Hodel (2013, fig. 43) and Fernández & Gottschalk (2017, page 130). There is one unusual population in northeastern Dominican Republic. This comprises two specimens from near Cabrera. One of these (Montrero 433) has a slightly costapalmate leaf and shorter pedicels, and fruits mature from white to reddish-purple. The second specimen (Zanoni 35835) has longer pedicels. A few other specimens, from scattered localities, have unusually long pedicels.

Figures

FIGURE 18. Distribution of C. spissa, C. torrida, and C. yunquensis.

PLATE 26. Coccothrinax spissa, Dominican Republic, with swollen stems. (Image by Eladio Fernández).