Pholidostachys pulchra Wendl. ex Burret (1930: 130)

Henderson, Andrew, 2012, A revision of Pholidostachys (Arecaceae), Phytotaxa 43, pp. 1-48 : 13-15

5. Pholidostachys pulchra Wendl. ex Burret (1930: 130) .

Calyptrogyne pulchra (Wendl. ex Burret) Wessels

Boer, 1968: 74. Type: COSTA RICA. Heredia: “flum. Sarapiquí”, 1857, H. Wendland s. n. (holotype GOET n.v., isotype K!).

Stems 3.7(1.5–6.6) m long, 4.6(3.0–8.0) cm diameter, solitary or rarely clustered. Leaves 12(7–23) per stem; sheaths 32.1(20.0–48.0) cm long; petioles 85.3(49.0–150.0) cm long; rachises 70.5(32.0–130.0) cm long, 6.8(3.3–13.1) mm diameter; pinnae 6(3–9) per side of rachis; basal pinna 48.1(35.5–61.0) cm long, 1.2(0.4– 3.0) cm wide, forming an angle of 62(42–93)° with the rachis; apical pinna 40.3(30.0–54.0) cm long, 11.3(4.0–20.0) cm wide, forming an angle of 16(11–27)° with the rachis. Inflorescences spicate, with a welldeveloped peduncle, absent rachis, and 1 rachilla, this arching or erect at anthesis; prophylls 14.8(5.0–29.0) cm long; peduncular bracts 31.4(12.5–59.0) cm long, inserted 3.4(1.1–10.0) cm above the prophyll; peduncles 13.1(4.5–33.0) cm long, 5.7(3.6–11.8) mm diameter; rachilla 1, 37.2(7.5–85.0) cm long, 9.4(6.2–16.2) mm diameter; proximal lips of flower pits regularly shaped, rounded, completely covering pits before anthesis and not recurved; fruits compressed, obovoid in lateral view with an asymmetric base, ellipsoid in frontal view, with a pronounced longitudinal ridge on one side and several lesser ridges on opposite side, 22.3(11.5–29.2) mm long, 11.1(6.6–14.6) mm diameter.

Distribution and habitat. From 11°22’– 3°10’N and 76°13’– 84°24’W in Nicaragua, Costa Rica, Panama, and western Colombia at 331(12–1000) m elevation in lowland rainforest ( Fig. 6 ).

Taxonomic notes. Pholidostachys pulchra shares with P. panamensis a spicate inflorescence and unequal prophyll and peduncular bract. It is a widespread and variable species.

Subspecific variation. Pholidostachys pulchra occurs in at least six geographically separate populations. However, no subspecific division is made here for two reasons. It is not clear if the gaps between some of the populations are artifacts of insufficient collecting, and in most cases there are too few specimens to test for differences amongst populations.

From the north, at low elevations of 245(15–750) m in Nicaragua and Costa Rica there is a large and apparently uniform population. This population has proximal lips that are slightly different from other populations; they are wider than long and the apex of each lip slightly overlaps the bases of the next two, distal lips ( Fig. 3C , left). One specimen from near Puerto Viejo in Costa Rica is reported to have clustered stems; all others are solitary. There is a single outlier in Costa Rica, from the Osa Peninsula.

The gap between the Nicaraguan and Costa Rican population and the next, in Veraguas, Panama appears real since there are collections of many other palms from the intervening region. The Veraguas population occurs at higher elevations of 712(400–1000) m and has shorter stems, smaller leaves, smaller inflorescences, and larger fruits than the Nicaragua / Costa Rica population.

The next population, in Coclé, Panama, occurs at slightly lower elevations at 519(100–775) m. It has shorter and narrower apical pinnae with a narrower angle and longer peduncular bracts and interbract distances than other populations. One specimen from here is reported to have clustered stems.

The next population occurs east of the Canal Zone, in three areas, the Santa Rita Ridge, Cerro Brewster, and the western end of the Serranía de San Blas. These are likely to represent collecting localities rather than populations, and all are treated together. This population occurs also occurs at slightly lower elevations at 426(200–850) m. It has longer stems, longer and wider rachises, longer and wider peduncles, and longer and wider rachillae than other Central American populations. One specimen (de Nevers 5206) has an unusually short inflorescence. In this population, several specimens are reported to have clustered stems. This and other Panamanian populations (Veraguas, Coclé) have different proximal lips from the Costa Rican/Nicaraguan population; they are usually longer than wide and do not overlap the two distal lips ( Fig. 3C , right). However, a few specimens from San Blas have proximal lips more like the Costa Rican/Nicaraguan population.

Almost 500 km further south, there are two populations in western Colombia. One of these, from near Quibdó at 356(200–450) m elevation, comprises several specimens that have unusually short inflorescences and smaller fruits. These tend to have the inflorescence bracts surrounding, although not covering, the rachilla at anthesis.

Furthest south, from Valle at 129(12–600) m elevation, there are several specimens that also have unusually small fruits, like those of the population from near Quibdó. However, unlike that population, the Valle specimens have the longest rachillae of any population of Pholidostachys pulchra .

Figures

FIGURE 3. A. Proximal lips of flower pits irregularly shaped, often acute or acuminate, completely covering pits before anthesis (Pholidostachys dactyloides; left de Nevers 8402, right Arguëllo 477). B. Proximal lips of flower pits regularly shaped, rounded, completely covering pits before anthesis and not recurved (P. panamensis; de Nevers 6767). C. Proximal lips of flower pits regularly shaped, rounded, completely covering pits before anthesis and not recurved (P. pulchra; left Henderson 712, right Henderson 59). D. Proximal lips of flower pits regularly shaped, rounded, not covering pits before anthesis, recurved (left P. occidentalis, Henderson 138; right P. synanthera subsp. synanthera, Henderson 161). Scale bar = 1 cm.

FIGURE 6. Distribution maps of Pholidostachys pulchra, P. sanluisensis, P. synanthera subsp. synanthera, and P. synanthera subsp. robusta.