PALMS Baker & Heatubun: Biak and Supiori Palms New Palms from Biak and Supiori, Western New Guinea Vol. 56(3) 2012 WILLIAM J. BAKER Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AB, United Kingdom w.baker@kew.org AND CHARLIE D. HEATUBUN Fakultas Kehutanan, Universitas Papua, Jl. Gunung Salju, Amban, Manokwari 98314, Papua Barat, Indonesia charlie_deheatboen@yahoo.com 1. View from Samber across the limestone cliffs of western Biak. (Photo: W.J. Baker) The Indonesian islands of Biak and Supiori sit at the mouth of Cenderawasih Bay, the broad arc of ocean to the north of the neck of New Guinea’s Bird’s Head Peninsula. Already known for their remarkable animal endemism, the islands are home to four unique palm species, three of which are described here for first time. PALMS 56(3): 131–150 131 PALMS Baker & Heatubun: Biak and Supiori Palms Of the many islands scattered around Cenderawasih Bay (also known as Geelvink Bay), Biak, Supiori, Numfor and Yapen stand out on account of their relatively large size. Yapen, a land bridge island, sits close to the New Guinea mainland to which it was once connected, while the remaining three are oceanic in origin and located in the north of the bay. Biak forms an island pair with the smaller Supiori, the two being separated only by a narrow channel, and Numfor is located some 60 km to the south-west. Together, Biak and Supiori measure some 125 km in length and 40 km at the widest point. In common with other islands in the region, they are dominated by rugged limestone (Fig. 1) perforated by sink-holes and caves, with sporadic occurrences of other geologies. Biak played an important role in World War II and was the scene of some of the bloodiest fighting in the Pacific. The Japanese made use of some of Biak’s caves as bases and defensive position, but were ultimately defeated by Allied forces after a bitter stand-off. Biak’s large airstrip dates back to that time and has allowed Biak to function as a hub for air travel in the region. The relative accessibility of Biak by boat and air has no doubt contributed to the degradation of the island’s rain forest, much of which has now been destroyed. The North Biak Island Reserve encompasses a portion of the northern tip of the island and much of Supiori is also protected, although the effectiveness of these reserves is not clear. Some unprotected areas of the interior of the island also appear to retain good forest, though further analysis of the condition of the remaining primary vegetation is urgently required. The plants of Biak and Supiori are poorly known. The palms, however, have been the subject of a series of expeditions to Biak, two led by Rudi Maturbongs with colleagues from Universitas Negeri Papua in 1998 and 2001, and three involving the authors and various colleagues from Universitas Negeri Papua, Herbarium Bogoriense and the Royal Botanic Gardens, Kew in 2000, 2009 and 2010. The 2001 expedition also included a short visit to Supiori. As a result of these expeditions, we have obtained sufficient material for the description of four remarkable new endemic species, three from Biak and one from Supiori. The first of these, Hydriastele dransfieldii was described following the expeditions led by Maturbongs (Baker et al. 2000). This palm had 132 Vol. 56(3) 2012 already been introduced to cultivation prior to its formal description but was poorly known in the wild until these expeditions. The remaining three new species are described here for the first time. As a whole, the palm flora of Biak is not particularly rich (Table 1). Nineteen species have been recorded, with all non-endemic species being shared with mainland New Guinea. Widespread New Guinean species are present, such as Arenga microcarpa, Caryota rumphiana and Hydriastele costata, as well as two that are distinctive western New Guinean species, Pigafetta filaris and Pinanga rumphiana (Figs. 2 & 3). The Biak palm flora also includes several widespread New Guinea rattan species such as Calamus aruensis, C. heteracanthus, C. pachypus, C. vitiensis, C. zebrinus and Korthalsia zippelii. Of Biak’s non-endemic palms, only Calamus dasyacanthus and Hydriastele brassii (Back Cover) could be regarded as less well known. Our knowledge of the palm flora of Supiori is less complete. We expect that it is likely to be broadly similar to that of Biak, although the presence of a high peak (>1000 m) and somewhat different geology (Masria et al. 1981) may result in the occurrence of additional montane species. In contrast to the relatively ordinary nonendemic palm flora, the endemic palms are remarkable in various ways. Hydriastele dransfieldii was originally described in Siphokentia (Baker et al. 2000), a genus that was later reduced into synonymy with Hydriastele, following in depth molecular phylogenetic studies (Baker & Loo 2004, Loo et al. 2006). While this taxonomic change is corroborated by morphology, the two species formerly accepted in Siphokentia (H. dransfieldii and the Moluccan H. beguinii) remain a distinctive pair of sister species within Hydriastele, characterized by the fused petals and sepals in the female flower. We found H. dransfieldii to be widespread on limestone in Biak and abundant in places. Occasionally, it can even be observed in disturbed roadside vegetation, although it is unlikely to be regenerating in such secondary habitats. Hydriastele dransfieldii has been reported (sight records only) from Numfor and Supiori, but the species is not known from Yapen or mainland New Guinea. The three remaining endemic species, described as new to science below, are apparently far less common on Biak and face a greater threat of extinction. Like H. dransfieldii, they are palms of limestone, two Supiori Actinorhytis calapparia (Blume) H.Wendl. & Drude ex Scheff. Sight record (cultivated?) – Adonidia maturbongsii W.J.Baker & Heatubun Heatubun et al. 971 – Arenga microcarpa Becc. Maturbongs et al. 548 – Calamus aruensis Becc. Sight record Jitmau et al. 308 Calamus dasyacanthus W J. Baker & al. Maturbongs et al. 687 – Calamus heteracanthus Zipp. ex Blume Baker et al.1334 – Calamus pachypus W J. Baker & al. Sight record – Calamus vitiensis Warb. ex Becc. Maturbongs et al. 568 – Calamus zebrinus Becc. Baker et al.1340 Maturbongs et al. 683 Calyptrocalyx sp. – Maturbongs et al. 681 Caryota rumphiana Mart. Sight record – Heterospathe porcata W.J.Baker & Heatubun – Maturbongs et al. 680 Hydriastele biakensis W.J.Baker & Heatubun Baker et al. 1342 – Hydriastele brassii (Burret) W.J.Baker & Loo Baker et al. 1339 Maturbongs et al. 679 Hydriastele costata F.M.Bailey Maturbongs et al. 573 – Hydriastele dransfieldii (Hambali & al.) W.J.Baker & Loo Maturbongs et al. 555 – Korthalsia zippelii Blume Sight record Maturbongs et al. 684 Licuala sp. Heatubun et al. 972 Maturbongs et al. 682 Nypa fruticans Wurmb. Sight record – Pigafetta filaris (Giseke) Becc. Maturbongs et al. 565 – Pinanga rumphiana (Blume) J.Dransf. & Govaerts Maturbongs et al. 558 – Vol. 56(3) 2012 Biak Baker & Heatubun: Biak and Supiori Palms 133 Species PALMS Table 1. Checklist of the palms of Biak and Supiori. Where available, a voucher to substantiate the record is given, though additional vouchers are available for many of these species (specimens at K, variously duplicated at MAN, BO, AAU, NY and FTG). Sight records for species lacking vouchers were made by the authors in 2009 and 2010. A dash indicates that a species has not been observed. PALMS Baker & Heatubun: Biak and Supiori Palms Vol. 56(3) 2012 2. Pigafetta filaris, a common palm in disturbed vegetation on Biak. (Photo: W.J. Baker) of which (like H. dransfieldii) show biogeographic relationships with species on islands to the north-west, remarkable in view of the much greater species pool in nearby New Guinea to the south. All three represent significant additions to our knowledge of the palms of the New Guinea region and serve to focus attention on the importance and plight of Biak’s dwindling rain forest. Taxonomic treatment 1. Adonidia maturbongsii W.J.Baker & Heatubun, sp. nov. Type: Indonesia, Papua, 134 Biak Island: forest on the road side, main road from North Biak Nature Reserve to Biak town, July 2009, Heatubun et al. 971 (holotype K, isotypes BO, FTG, MAN, NY). (Figs. 4–11) Diagnostic characters: Adonidia maturbongsii is distinguished from A. merrillii by the arching leaf, broad, pendulous leaflets in a single plane, wide, concave leaflet tips and staminate flowers containing 30–32 stamens. Medium, solitary, mid-story to emergent palm. Stem 10–15 m tall, 10–20 cm in diam., tapering towards apex, surface brown with PALMS Baker & Heatubun: Biak and Supiori Palms Vol. 56(3) 2012 3. Pinanga rumphiana, Biak. (Photo: W.J. Baker) white blotches, leaf scars prominent, internodes 2–4 cm apart. Leaves ca. 10 in crown, arching; sheath 60–70 cm long, pale, dull green, with thin grey scurfy indumentum with scattered purple-brown scales, somewhat eroded or fibrous at mouth, forming crownshaft 80–90 cm × 10–12 cm; petiole 26–45 cm long, channelled adaxially, rachis 2.5–3 m long, indumentum as on sheath; leaflets 25–30 pairs each side of the rachis, regularly arranged (or somewhat subregularly), in one plane, drooping or pendulous in emergent individuals, slightly discolorous, with persistent reins attached to lowermost 135 PALMS Baker & Heatubun: Biak and Supiori Palms Vol. 56(3) 2012 4. Adonidia maturbongsii. A. Habit. B. Leaf apex. C. Mid-leaf portion. D. Inflorescence. E. Portion of rachilla with triad. F. Staminate flower. G. Pistillate flower in section. H. Fruit whole and in section. I. Endocarp showing longitudinal fibers. Scale bar: A = 2 m; B–D = 6 cm; E = 1.5 cm; F, G = 7mm; H, I = 7 mm. From Heatubun et al. 971, except A from photograph and F from Baker et al. 1338. Drawn by Lucy T. Smith. 136 PALMS Baker & Heatubun: Biak and Supiori Palms Vol. 56(3) 2012 5. Adonidia maturbongsii on the outskirts of Kota Biak. (Photo: W.J. Baker) pair of leaflets, with minute brown punctate scales and scattered medifixed ramenta abaxially; middle leaflets 40–49 cm long, 9–12 cm wide, oblanceolate, cucullate, apex obliquely praemorse, concave, transverse veinlets inconspicuous; terminal leaflets linear or narrowly elliptic, apex truncate, praemorse. Inflorescence 60–70 cm long, infrafoliar, protandrous, divaricate, patent, deflexed in fruit, branched to 4 orders, axes white, rubbery, with caducous floccose orange-brown indumentum when young; prophyll 24–26 cm long, 6–8 cm wide, greenish white, splitting apically, caducous later; first peduncular bract 137 PALMS Baker & Heatubun: Biak and Supiori Palms 31–35 cm × 5–7 cm, attached 15–20 mm above prophyll insertion, exserted from prophyll apex and enclosing inflorescence prior to anthesis, caducous later; peduncle 8–14 cm long, 2–2.5 cm wide, scurfy indumentum of Vol. 56(3) 2012 black-brown scales basally; primary branches 25–28, longest primary branch (basalmost) 40–65 cm; rachillae 8–19 cm long, 1.5–3.5 mm in diam., triads 3–9 mm apart, spirally arranged. Staminate flower 6.5–8 mm long, 6 (top). Adonidia maturbongsii, a young specimen emerging from the canopy with less pendulous leaflets than adults, Samber forest, Biak. 7 (bottom). Adonidia maturbongsii leaf. (Both photos: W.J. Baker) 138 PALMS Baker & Heatubun: Biak and Supiori Palms 2.5–3.2 mm in diam. in bud; sepals 2–2.4 mm long, ca. 3 mm wide, rounded, thickened; petals 7–7.5 mm long, ca. 3 mm wide, bony, narrowly elliptic; stamens 30–32, 4.5–6 mm Vol. 56(3) 2012 long; filaments 1.5–4 mm long, briefly connate at base, awl-shaped; anthers 3–3.8 mm long, 0.5–0.8 mm wide, dorsifixed near the base, dehiscence latrorse, connective dark; pistillode Adonidia maturbongsii. 8 (upper left). Inflorescence at staminate anthesis, held by Charlie Heatubun. 9 (upper right). Staminate flowers. 10 (bottom). Infructescence. (All photos: W.J. Baker) 139 PALMS Baker & Heatubun: Biak and Supiori Palms Vol. 56(3) 2012 11. Adonidia maturbongsii, fruits. (Photo: W.J. Baker) ca. 5 mm long, 1.2–1.4 mm in diam., lageniform. Pistillate flower 4.5–5 mm long, 140 ca. 4.5 mm in diam., borne in proximal half to two-thirds of the rachilla; sepals 3–4 mm PALMS Baker & Heatubun: Biak and Supiori Palms long, 4–4.5 mm wide, thickened, rounded; petals 4–4.5 mm long, 3–3.5 mm wide, similar to sepals; staminodes few, minute, tooth-like; gynoecium ca. 4 mm long, ca. 3 mm in diam., pyriform, stigmas at anthesis not seen. Fruit 24–31 mm long, 14–16 mm in diam., ellipsoid, ripening through orange to red, perianth cupule clasping; endocarp 23–30 mm long, 12–12.5 mm in diam., straw-colored with thick longitudinal fibers, closely adhering to seed. Seed 14–20 mm long, 9.5–12 mm in diam., ellipsoid; endosperm ruminate; embryo basal. Distribution: Scattered throughout Biak Island. Habitat: Lowland forest on limestone with thin soils and many sink holes, 80–170 m elevation. Vernacular names: Manjek (Biak dialect) Uses: Stem used for flooring and pillars in traditional houses. Conservation status: Endangered (EN B1, 2 (a, b [i, ii, iii, iv, v]), C2a (i); IUCN 2001). Though widespread on Biak, many sites for this species are threatened by ongoing forest degradation. The species is protected in the North Biak Nature Reserve. Specimens examined: Indonesia, Papua, Biak Island: forest on the road side, main road from North Biak Nature Reserve to Biak town, July 2009, Heatubun et al. 971 (holotype K, isotypes BO, FTG, MAN, NY); North Biak Nature Reserve, Sansundi village, September 1998, Maturbongs et al. 559 (BO, K, MAN), Maturbongs et al. 560 (BO, K, MAN); Samber forest, July 2009, Baker et al. 1336 (BO, K, FTG, MAN), Baker et al. 1338 (BO, K, FTG, MAN); locality uncertain (given incorrectly on the label as Merauke district, but number sequence indicates the collector was active in Biak), June 2001, Maturbongs et al. 686 (AAU, BO, FTG, K, MAN). Notes: It has been known for some time that an undescribed species from subtribe Ptychospermatinae occurs on Biak (Baker pers. obs. 2000, Zona 2000). The species appears to have been first recorded by Greg Hambali who introduced it to cultivation as Drymophloeus “veitchioides,” an unpublished name under which it persists in some collections today. However, new molecular phylogenetic data provide evidence that the species is most closely related to Adonidia merrillii, the sole species of a hitherto monotypic genus restricted to parts of the Philippines and far Vol. 56(3) 2012 northern Borneo (Zona et al. 2011). Although the study was based on only two DNA regions and the relationships only moderately supported by the data, we describe the new species as Adonidia maturbongsii as the best solution given the available data and because of morphological similarities discussed below. Generic limits in subtribe Ptychospermatinae are fine and sometimes problematic (Zona 1999, Dransfield et al. 2008), as evidenced by the initial, but erroneous assignment of this new species to Drymophloeus, a genus that has experienced substantial changes in circumscription recently (Zona et al. 2011). Nevertheless, A. maturbongsii and A. merrillii share a combination of features that lends support to a close relationship between the two. Both species are moderately robust palms of limestone habitats that bear white inflorescences branched up to four orders. They produce red fruit with endocarps covered in pale, flattened, longitudinal fibers interspersed with finer fibers and seeds with ruminate endosperm. Nevertheless, A. maturbongsii is very different from its congener, most obviously in its arching leaf with broad, pendulous leaflets in a single plane with wide, concave, praemorse tips (in contrast to the ascending, narrower leaflets in slightly different planes with less conspicuously praemorse tips in A. merrillii). In addition, the staminate flowers of A. maturbongsii contain 30–32 stamens compared to 45–50 in A. merrillii. Adonidia merrillii is a geographically disjunct species, occurring to the west of Wallace’s Line whereas all other Ptychospermatinae occur to the east of this important biogeographic interface (Baker & Couvreur 2012). The expansion of the genus elaborates this biogeographic story. The link between New Guinea and the Philippines has been explained by westward stepping-stone dispersal along the Philippine-Halmahera arc during the Neogene (Zona et al. 2011), which may also account for similar biogeographic links in other taxa, such as the palm genera Heterospathe and Orania, and Sararanga in the Pandanaceae (Baker et al. 1998, Norup et al. 2006). Adonidia maturbongsii is named for our friend and collaborator Rudi Maturbongs of Universitas Negeri Papua, the collector of the first herbarium specimens of the new species, in recognition of his contributions to palm exploration in Biak. 141 PALMS Baker & Heatubun: Biak and Supiori Palms 2. Heterospathe porcata W.J. Baker & Heatubun, sp. nov. Type: Indonesia, Papua, Supiori Island: North Supiori Nature Reserve, Fanjur village, June 2001, Maturbongs et al. 680 (holotype K; isotypes AAU, BO, CANB, LAE, MAN). (Fig. 12) Diagnostic characters: Heterospathe porcata is distinguished from other species in the genus by its inflorescence with elongate peduncle, the peduncular bract inserted in the proximal half of the peduncle, and the fruit with a bony endocarp with 6–7 longitudinal ridges. Slender, ?solitary, understory palm. Stem to ca. 6 m tall, ca. 3 cm in diam.; leaf scars prominent; internodes 1–2 cm. Leaves 16 in crown; sheath open, margins eroded, not forming crownshaft; petiole ca. 50 cm long, adaxially channeled; rachis ca. 100 cm long, with sparse, floccose indumentum of orangebrown scales throughout; leaflets ca. 40 each side of rachis, regularly arranged, borne up to 3.5 cm apart, somewhat discolorous, basifixed ramenta scattered on proximal part of adaxial surface of midribs and major veins; middle leaflet ca. 45 cm long, 2–2.3 cm wide, linear, somewhat sigmoid at tip and base, tip narrowly attenuating, transverse veinlets inconspicuous. Inflorescence 124–138 cm long, interfoliar, elongate, brush-like, branched to 2–3 orders; prophyll ca. 39 cm long, 1.5–2 cm wide, splitting apically, with lepidote indumentum of dark scales; first peduncular bract, ca. 69 cm long, ca. 2 cm wide, similar to prophyll, splitting apically to one side, indumentum as prophyll, attached one third to halfway above the peduncle base; peduncle 102–108 cm long, 5.5–7.5 mm wide, with thin, dark brown tomentum and throughout all inflorescence branches; primary branches 9–13, to 28 cm long, 1.5–4 cm apart, with up to 14 rachillae; rachillae 10–17 mm long, 0.9–1.5 mm in diam., swept forward at an acute angle to the rachis, sinuous, with thin dark brown tomentum; rachilla bracts inconspicuous; triads 2–3.5 mm apart, spirally arranged. Male flower ca. 2 mm long, ca. 1.8 mm in diam. in young bud; sepals 3, ca. 1 mm long, ca. 1.5 mm wide, concave, imbricate; petals 3, ca. 1.5 mm long, ca. 1.3 mm wide, cucullate, valvate; stamens 6; filaments ca. 0.6 mm long, connate in a ring at base, linear; anthers ca. 0.8 mm long, ca. 0.3 mm wide, oblong, dorsifixed, connective dark; pistillode 0.6 mm long, 0.3 mm in diam., cylindrical. Female flower ca. 4 mm long, ca. 3.5 mm in diam., borne in proximal half of the rachillae 142 Vol. 56(3) 2012 only, bracteole forming conspicuous perianthlike cupule; sepals 3, ca. 2.5 mm long, ca. 3 mm wide, concave, imbricate; petals 3, ca. 3.6 mm long, ca. 2.5 mm wide, concave with short, triangular apical lobe, imbricate; staminodes ca. 2, linear, ca. 0.6 mm long; gynoecium ca. 3.5 mm long, ca. 1.5 mm in diam., ellipsoid, stigma inconspicuous. Fruit ca. 2 cm long, ca. 9 mm diam. (measured from dry material), ellipsoid, pericarp shrinking around endocarp ridges when dried, stigmatic remains eccentrically apical, red; perianth cupule clasping; endocarp ca. 2 cm long, ca. 8.5 mm in diam., ellipsoid, dark brown, bony, with 6–7 thickened, fibrous ribs radiating from the stigmatic remains and running the length of the fruit to the base. Seed immature, starshaped in section, conforming to inner contours of endocarp; endosperm ruminate; embryo basal. Distribution: Recorded from only one locality on Supiori Island. Habitat: Secondary limestone forest dominated by Myristica, Intsia and Lepiniopsis at an elevation of ca. 30 m. Vernacular names: Not known. Uses: The stem is used for making bows and the fruit is used as a betel nut substitute. Conservation status: Data deficient (IUCN 2001). Current knowledge of populations of this palm and the condition of the forests on Supiori is insufficient for a conservation assessment to be completed at this time. Specimens examined: Indonesia, Papua, Supiori Island: North Supiori Nature Reserve, Fanjur village, June 2001, Maturbongs et al. 680 (holotype K; isotypes AAU, BO, CANB, LAE, MAN). Notes: Heterospathe has two centers of diversity, the Philippines and New Guinea. In New Guinea, species diversity is biased towards the eastern half of the island and montane elevations – around 90% of all New Guinea Heterospathe specimens have been collected from Papua New Guinea and more than 75% from elevations above 500 m. An undescribed species from the lowlands of an offshore island of western New Guinea is thus an unexpected discovery. Superficially, H. porcata is similar to Heterospathe elegans, although the nearest record for this species is some 500 km away to the south-east (Trudgen & Baker 2008). The PALMS Baker & Heatubun: Biak and Supiori Palms Vol. 56(3) 2012 12. Heterospathe porcata. A. Leaf apex and mid-leaf portion. B. Inflorescence in two halves. C. Detail of rachilla. D. Rachilla with pistillate flowers, one removed to show large floral bracteole. E. Staminate flower whole and in section. F. Pistillate flower in section. G. Endocarp in two views. Scale bar: A, B = 8 cm; C, D = 7 mm; E = 2 mm; F = 3mm; G = 1 cm. From Maturbongs et al. 680. Drawn by Lucy T. Smith. 143 PALMS Baker & Heatubun: Biak and Supiori Palms two species share a slender habit, finely pinnate leaf and inflorescence with elongate peduncle and branches clustered near the apex. Heterospathe porcata appears to be a taller palm, recorded as 6 m in contrast to the reported maximum of 2.5 m for H. elegans. The inflorescence is also quite different, being branched to 2 or 3 orders (1 or 2 orders in H. elegans), the rachillae being finely sinuous (more irregularly so in H. elegans) and the first peduncular bract being rather long and inserted one third to halfway along the peduncle from the base (shorter in H. elegans and inserted in the distal quarter of the peduncle). Unusually, the fruit contains a thin, bony endocarp with 6 or 7 thickened, parallel, fibrous ridges running the full length of the fruit (hence the species epithet porcata, meaning ridged). These reveal themselves when the ellipsoid fruit, which are larger than the globose fruit of H. elegans, are dried and the mesocarp shrinks around the ridges. The space with the endocarp is somewhat star-shaped in cross section and, consequently, so is the seed, in contrast to the globose seed of H. elegans. Within Heterospathe, the only species with a comparable endocarp is H. longipes of Fiji, though this has much more extremely ornate structures. The combination of its geographical and elevational distribution, and almost unique reproductive morphology renders H. porcata a very surprising novelty indeed. 3. Hydriastele biakensis W.J.Baker & Heatubun sp. nov. Type: Indonesia, Papua, Biak Island: Oridek district, Wadibu village, July 2009, Baker et al. 1342 (holotype K, isotypes AAU, BO, MAN). (Figs. 13–19) Diagnostic characters: Hydriastele biakensis is distinguished from other species in the genus by its large size, the recurving leaves with ascending leaflets and acute or notched leaflet apices, the often somewhat distorted prophyll bearing pronounced pithy keels, the peduncle abruptly constricting at the prophyll scar, the inflorescence branched to four orders, the highly sinuous rachillae, and the congenitally open staminate flowers. Robust, solitary, canopy palm. Stem ca. 15 m tall, ca. 30 cm in diam., leaf scars prominent, internodes 3–7 cm, surface brown. Leaves ca. 18–24 in crown, strongly recurved; sheath ca. 170 cm long, pale green with white waxy indumentum, striate near mouth, forming crownshaft 200–270 cm long, 26–27 cm wide; rachis 280–300 cm long, petiole 47–50 cm 13. Hydriastele biakensis, cultivated at Marau, Biak. (Photo: W.J. Baker) 144 Vol. 56(3) 2012 PALMS Baker & Heatubun: Biak and Supiori Palms Vol. 56(3) 2012 14. Hydriastele biakensis, cultivated at Marau, Biak. (Photo: W.J. Baker) long, 3.5–5 cm wide, channeled adaxially, petiole and lower rachis yellowish green, petiole and rachis bearing scattered to dense brown, caducous, felty indumentum and minute dark dots throughout; leaflets ca. 65 each side of rachis, regularly arranged, strongly ascending, concolorous, with minute dark dots abaxially, brown, basifixed ramenta attached 145 PALMS Baker & Heatubun: Biak and Supiori Palms Vol. 56(3) 2012 15. Hydriastele biakensis. A. Leaf apex and mid-leaf portion. B. Inflorescence base. C. Inflorescence first order branch. D. Rachilla showing congenitally open flowers. E. Rachilla with pistillate flowers at anthesis. F. Staminate flower. G. Pistillate flower whole and in section. H. Sinuous rachilla with fruit attached. I. Fruit in section. Scale bar: A,C = 6 cm; B = 8 cm; D, H = 1.5 cm; E, I = 1 cm; F = 5 mm; G = 3 mm. A–C from Baker et al. 1342, D–I from Heatubun et al. 970. Drawn by Lucy T. Smith. 146 PALMS Baker & Heatubun: Biak and Supiori Palms to basal, abaxial portion of midrib; middle leaflets 121–126 cm long, 3–4.5 cm wide, linear, transverse veinlets conspicuous, apices narrowly acute; terminal segments linear, with apices notched, not praemorse. Inflorescence 95–100 cm long, infrafoliar, ?protandrous, horsetail-shaped, erect, branched to 4 orders, axes white on emergence, turning green; prophyll 70–107 cm long, 15–18 cm wide, green, often somewhat sinuous, appearing distorted, keels pithy, with thin, white indumentum; first peduncular bract, ca. 70 cm long, ca. 5.5 cm wide, similar to prophyll, attached 2.5–4.5 cm above prophyll insertion; peduncle 10–21 cm long, 8–8.5 cm wide at base, narrowing sharply above prophyll insertion to 3–3.5 cm, prophyll scar conspicuous with rounded “shoulders”; primary branches 20–22, the longest (basalmost) to 70 cm; rachillae 32–48 mm long, 2–3 mm in diam., sinuous, especially distally, triads 2–3 mm apart, decussate. Staminate flower 5–6.5 mm long, 2.5–4 mm in diam. in bud, variously flattened and distorted, congenitally open; sepals connate in a shallow cup with three triangular lobes ca. 0.5 mm long, white; petals 5–6 mm long, 1–1.5 Vol. 56(3) 2012 mm wide, narrowly triangular, variously twisted and sinuous, briefly adnate to receptacle, white; stamens 6, 4.5–5.5 mm long, white; filaments ca. 0.5 mm long, narrowly conoid; anthers 4–5 mm long, 0.8–1.2 mm wide, oblong to sinuous, basifixed, dehiscence latrorse; pistillode minute, pyriform. Pistillate flower ca. 2.5 mm long, 2.5–2.8 mm in diam., borne throughout the rachillae; sepals imbricate, ca. 1 mm long, 2.5–2.8 mm wide, rounded, white; petals 2–2.5 mm long, 2.5–3 mm wide, strongly imbricate, rounded, white; staminodes 3, minute, paddle-shaped; gynoecium ca. 2 mm long, ca. 1.5 mm in diam., globose; stigma minutely trifid. Fruit 9.5–12 mm long, 5–6 mm in diam., oblongellipsoid, red, perianth cupule clasping, endocarp thin, tough, closely adhering to seed. Seed 7.5–8.2 mm long, 4–4.3 mm in diam., cylindrical; endosperm homogeneous; embryo basal. Distribution: Known from few specimen localities and sight records on the south and western coast of Biak and Auki Island on the nearby Padaido Islands. Hydriastele biakensis. 16 (left). Inflorescences. 17 (right). Infructescences. (Both photos: W.J. Baker) 147 PALMS Baker & Heatubun: Biak and Supiori Palms Vol. 56(3) 2012 Habitat: Coastal forest on limestone near to sea level, sometimes on limestone cliffs close to the beach. Vernacular names: Arwaf (Biak dialect) Uses: The stem is used for flooring and the leaf sheaths for making baskets. Conservation status: Endangered (EN B1, 2 (a, b [i, ii, iii, iv, v]), C2a (i); IUCN 2001). This species is known only from coastal limestone forest which is severely degraded on Biak, especially on the south coast. Larger populations have been observed on the west coast and Padaido Islands. Specimens examined: Indonesia, Papua, Biak Island: Oridek district, Wadibu village, July 2009, Baker et al. 1342 (holotype K, isotypes AAU, BO, MAN), Heatubun et al. 970 (BO, K, MAN, NY). A sterile specimen may also represent this species: northern Biak, Wari village, September 1998, Maturbongs et al. 574 (BO, K, MAN). Notes: We became aware of this beautiful species during the brief visit to Biak in 2000 (Baker pers. obs.) when it was seen cultivated near the now ruined Marau Beach Hotel and persisting wild as a few scattered individuals in cleared areas near the south coast. At that time, it was regarded as a species of Gulubia (now a synonym of Hydriastele) and suspected to be undescribed when compared with the species treated in Essig’s (1982) monograph of the genus. Unable to collect material at that time, we had to wait until 2009 for an opportunity to make complete specimens for herbarium and laboratory study. To determine the relationships of the new species, we exploited an earlier phylogenetic study of Hydriastele (Loo et al. 2006). Following the protocols of Loo et al., we generated new DNA sequence data for H. biakensis of the two low-copy nuclear genes PRK and RPB2, integrated these new data within their published dataset and repeated their analyses. Hydriastele biakensis was strongly supported as sister species of H. palauensis. There are morphological similarities between the two species in general appearance, such as the strongly recurved leaves, ascending leaflets with acute or notched (but not conspicuously praemorse) apices and the glaucous crownshaft. The two also share the unusual feature of the staminate flowers being congenitally open in bud due to the large size of the stamens relative to the petals (Fig. 18). 148 18. Hydriastele biakensis, congenitally open male flowers prior to anthesis. (Photo: W.J. Baker) This character, alongside fruit structure, was considered diagnostic for the genus Gulubiopsis in which H. palauensis was originally described (Beccari 1924, Beccari & Pichi-Sermolli 1955). Moore and Fosberg (1956) deemed these features inadequate to justify generic status, reducing Gulubiopsis into synonymy with Gulubia, which was later sunk into Hydriastele (Baker & Loo 2004). In addition to morphological similarities, the two species occupy similar coastal limestone habitats. Moreover, Biak is among the closest of the Malesian islands to Palau, although almost 1000 km of clear ocean exists between the two. Nevertheless, the two are clearly distinct species. Hydriastele biakensis is much more robust than H. palauensis, for example with stem diameter, leaf length, leaflet number, leaflet length, sheath length and inflorescence being twice the size or more in the former than that reported for the latter (Moore & Fosberg 1956, Essig 1982). The contrast is most clear in the inflorescence which, as well as being much smaller in H. palauensis, lacks the striking “shoulders” formed by the abrupt PALMS Baker & Heatubun: Biak and Supiori Palms Vol. 56(3) 2012 19. Hydriastele biakensis, on low limestone cliffs above the beach at Wadibu, Biak. (Photo: W.J. Baker) 149 Baker & Heatubun: Biak and Supiori Palms PALMS Vol. 56(3) 2012 constriction of the peduncle at the prophyll scar, and the highly sinuous rachillae (see p. 107), and in the material available to us (Lorence et al. 8304 [PTBG]) is branched to two rather than four orders. DRANSFIELD, J., N.W. UHL, C.B. ASMUSSEN, W.J. BAKER, M.M. HARLEY AND C.E. LEWIS. 2008. Genera Palmarum – the Evolution and Classification of Palms. Royal Botanic Gardens, Kew, Richmond. Acknowledgments ESSIG, F.B. 1982. A synopsis of the genus Gulubia. Principes 26: 159–173. We are grateful to many colleagues who provided comments on the manuscript, additional information or support in the field, lab or herbarium: Theo Ampnir, Deby Arifiani, Steve Bachman, Jim Clarkson, John Dransfield, Rachel Engstrand, Lauren Gardiner, Jeff Marcus, Justin Moat, Himmah Rustiami, Tim Utteridge and Scott Zona. We are especially grateful to Rudi Maturbongs for the important contributions he made in the earlier explorations of Biak’s palms. Fieldwork was funded by the Tobu fund, the BAT Biodiversity Partnership and the Royal Botanic Gardens, Kew. This paper is dedicated to the late Charles H. Uhl (1918–2010), a veteran of the war in Biak and husband of the great palm biologist, Natalie W. Uhl. References BAKER, W.J. AND A.H.B. LOO. 2004. A synopsis of the genus Hydriastele (Arecaceae). Kew Bulletin 59: 61–68. BAKER, W.J. AND T.L.P. COUVREUR. 2012. Biogeography and distribution patterns of Southeast Asian palms. In D. GOWER, K. JOHNSON, J.E. RICHARDSON, B. ROSEN, L. RÜBER and S. WILLIAMS (eds.). Biotic Evolution and Environmental Change in Southeast Asia. Cambridge University Press, Cambridge. Pp. 164–190. BAKER, W.J., R.A. MATURBONGS, J. WANGGAI AND G. HAMBALI. 2000. Siphokentia. Palms 44: 175–181. IUCN. 2001. IUCN Red List Categories and Criteria: Version 3.1. Species Survival Commission, IUCN, Gland, Switzerland and Cambridge. LOO, A.H.B., J. DRANSFIELD, M.W. CHASE AND W.J. BAKER. 2006. Low-copy nuclear DNA, phylogeny and the evolution of dichogamy in the betel nut palms and their relatives (Arecinae; Arecaceae). Molecular Phylogenetics and Evolution 39: 598–618. MASRIA, M., N. RATMAN AND K. SUWITODIRDJO. 1981. Geologi lembar Biak, Irian Jaya (The geology of the Biak Quadrangle, Irian Jaya). Geological Research and Development Centre, Bandung. MOORE, H.E. AND F.R. FOSBERG. 1956. The palms of Micronesia and the Bonin Islands. Gentes Herbarum 8: 423–478. NORUP, M.V., J. DRANSFIELD, M.W. CHASE, A.S. BARFOD, E.S. FERNANDO AND W.J. BAKER. 2006. Homoplasious character combinations and generic delimitation: a case study from the Indo-Pacific arecoid palms (Arecaceae: Areceae). American Journal of Botany 93: 1065–1080. TRUDGEN, M.S. AND W.J. BAKER. 2008. A revision of the Heterospathe elegans (Arecaceae) complex in New Guinea. Kew Bulletin 63: 639–647. BAKER, W.J., M.J.E. COODE, J. DRANSFIELD, S. DRANSFIELD, M.M. HARLEY, P. HOFFMANN AND R.J. JOHNS. 1998. Patterns of distribution of Malesian vascular plants. In R. HALL AND J.D. HOLLOWAY (Eds.). Biogeography and Geological Evolution of SE Asia. Backhuys, Leiden. Pp 243–258. ZONA, S. 1999. New perspectives on generic limits and relationships in the Ptychospermatinae (Palmae: Arecoideae). In A. HENDERSON and F. BORCHSENIUS (Eds.). Evolution, Variation and Classification of Palms. The New York Botanical Garden Press, New York. Pp. 255–263. BECCARI, O. 1924. Neue palmen Mikronesiens. Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie. 59: 11–16. ZONA, S. 2000. A personal history of Drymophloeus in New Guinea. Palms 44: 184–186. BECCARI, O. AND R.G. PICHI-SERMOLLI. 1955. Subfamiliae Arecoidearum palmae gerontogeae tribuum et generum conspectus. Webbia 11: 1–187. 150 ZONA, S., J. FRANCISCO-ORTEGA, B. JESTROW, W.J. BAKER AND C.E. LEWIS. 2011. Molecular phylogenetics of the palm subtribe Ptychospermatinae (Arecaceae). American Journal of Botany 98: 1716–1726.