Search

Randi, Agusti, Wijedasa, Lahiru S., Utteridge, Timothy M.A. (2022): Lophopetalum tanahgambut, a new endemic giant tree species from peat swamp forest of Sumatera, Indonesia, with the first pseudoverticillate leaf arrangement in genus Lophopetalum (Celastraceae). Phytotaxa 573 (1): 115-122, DOI: 10.11646/phytotaxa.573.1.7, URL: http://dx.doi.org/10.11646/phytotaxa.573.1.7

Lophopetalum tanahgambut Randi, Utteridge & Wijedasa, sp. nov. (Figs 1–2). Type:— INDONESIA. Sumatera Selatan Province: Musi Banyuasin Regency, Bayung Lencir District, Muara Medak Village, conservation area of PT Tri Pupajaya forest production concession, 10 m. elev., 1°45’30.66”S, 104°12’19.13”E, 17 April 2021, Randi GB-129 (holotype: BO!; isotypes: WAN!, FIPIA!, SING!). Diagnosis:— This species is the only known Lophopetalum with 3–4 leaves in a pseudoverticillate arrangement, leaf apex retuse to emarginate, petiole with a pair of ridges to conspicuously winged, panicles solitary in terminal leaf, calyx lobes much wider than long, disk convex, 5-angular with rounded corners, slightly thickened at lobe edges where the stamens are inserted. Large top canopy tree, up to 40 m tall and 105 cm dbh; buttresses narrow, to 1.8 m tall; stilt-roots absent or sometimes present on old trees; knee roots system wide, to 15 m around the tree, raised to 1.5 m high from the ground surface, smooth, milky white to greyish. Bark smooth, cracked longitudinally to flaky, light to dull grey, or milky white; inner bark pinkish orange to pale reddish brown; sapwood cream. Lateral branches pseudoverticillate from seedling to pole and sometimes to early mature tree stage; young twigs with 3–4 obtuse angular, glabrous, plain green to becoming light and dull brown by aging, nodes thickened. Leaves in pseudoverticils of 3–4, arranged at a single plane around the axils or somewhat unequally within a node; blade coriaceous, often obovate or elliptic, sometimes lanceolate to oblanceolate, 6.1–12.4 × 3.0– 6.6 cm; base cuneate to slightly winged onto petiole; margin entire, recurved; apex retuse to emarginate or sometimes shortly acuminate; adaxial surface flat, slightly bullate to furrowed above, dark green, glabrous, often with scattered black dots on young leaves; abaxial surface with visible scattered reddish-brown gland dots, pale green to whitish when fresh, glabrous; midrib prominent on both sides; secondary veins slender, 8–12 pairs, arching for whole length, anastomosing to margin, slightly raised on both sides or sometimes sunken adaxially; tertiary venation reticulate, visible on both sides when fresh, flat to sunken adaxially or sometimes slightly raised; young leaves pale reddish-brown, shiny. Petiole 0.7–1.2 cm long, stout, ascending, slightly twisted, with a pair of ridges to conspicuously winged, shallowly channelled or flat to slightly convex adaxially, rounded abaxially, yellowish green when fresh, glabrous, sometimes pruinose when old. Panicles borne from terminal leaf axils, solitary in an axil, up to 11.5 cm long, branching to 2-orders, each branchlets bearing solitary flower, glabrous throughout, dull white to yellowish cream or greenish white when fresh; peduncle 2.5–4.5 cm long; rachis and branches 4-angular; branches arranged (sub)opposite, spiral or in pseudoverticillate; bracts persistent, wide triangular, 1.0-1.4 × 1.9–3.5 mm, apex acuminate, drying early; bracteoles consistently in a pair at the end of branchlet, ca. 1.0 × 1.4 cm, thickened and fleshy. Flower buds short conical to ovoid, as high as wide or wider than high, 2.2–3.8 × 2.2–4.1 mm. Flowers 8.5–9.2 mm diameter at anthesis; pedicel 4.0– 6.4 mm long; calyx lobes widely ovate, much wider than long, ca. 1.1 × 2.2 mm, apex rounded or sometimes obtuse, margins erose, papillate outer side, milky white; petals 5, imbricate, triangular or sometimes elliptic-oblong, 3.8–4.1 × 2.8–3.0 mm, white, glabrous on both sides, apex rounded to obtuse, margins erose, translucent, appendage conspicuous on the inner side, slightly sunken and papillate on outer one; disk convex, 4–5 mm diameter, 5-angular with rounded corners, slightly thickened at lobes edges, dull white to pale yellow when fresh; stamens 5, inserted near disk lobes edge; filament whip-like, 1.3–1.8 mm long, thickened at base and tapering at the end; anther medifixed, ovoid, ca. 1.1 × 0.8 mm, base cordate, apex acute to slightly attenuate; pistil emerging 2.0– 2.2 mm above the disk; ovary partly immersed in the disk, distinctly pyramidal at half base then narrowed into a cylindrical style; ovule 3–5 in each cell. Fruit generally ellipsoid, rarely oblong, 3-lobed, 5.5–10.5 cm long, 2.4–3.2 cm at the widest point, distinctly three-lobed in cross section, greenish yellow when mature, glabrous and flat surface when fresh, apex shortly acuminate, split open while still hanging to release the winged seeds; dried fruit tuberculate on outer surface, rusty brown. Seed attached in the middle, surrounded by wing entirely, flattened, 4.4–5.6 × 1.2–1.5 cm (wing included), seed proper cream, wing milky white, drying early before fruit splits. Distribution:— The species is only known from peat swamp forests habitats in the type locality (Fig. 3). The type locality is a High Conservation Value Forest in a pulpwood concession on the border of Berbak Sembilang National Park. The peat swamp forest spans the border between Jambi and South Sumatra Provinces. A wider distribution in similar peat swamp forest habitats along the east coast of Sumatera is possible. However, large scale conversion and degradation of peatlands in the past has fragmented and reduced the extent of intact peat swamp forest. As this species has only been found in intact peat swamp forests and not degraded or restoration sites in areas adjacent areas to the type swamp forest its actual extent under current peatland conditions is most likely limited (Wijedasa et al., 2020). Ecology and phenology:— In intact peat swamp forest with soil conditions that are always wet to flooded. In its type location, this new species is relatively rare and its seedlings are found very far from mature trees, this is probably due to the mechanism of winged seeds dispersing the seeds far from the parent trees. Lophopetalum tanahgambut was observed flowering during February–April, and fruiting in April–June. Etymology:— The specific epithet ‘tanah gambut’ is formed from the Bahasa Indonesian words for peat soil or peat swamp habitat where this species is found. Vernacular name:— Kerupuk, Perupok (Palembang Malay); this vernacular name is also used for all species of the genus Lophopetalum, as well as several Kokoona species. Uses:— The wood is used locally for carpentry. Additional examined specimens:— INDONESIA. Sumatera Selatan Province: Musi Banyuasin Regency, Bayung Lencir District, Muara Medak Village, conservation area of PT Tri Pupajaya forest production concession, 10 m. elev., 31 January 2022, Randi GB-141 (BO); Sumatera Selatan Province: Musi Banyuasin Regency, Bayung Lencir District, Muara Medak Village, near Benu River, 10 April 2022, Randi GB-150 (BO). Provisional conservation status assessment:— Critically Endangered: CR A2cd C2a(i) (IUCN 2019). Lophopetalum tanahgambut grows in relatively undisturbed lowland peat swamp forest, which is protected by voluntary commitment of the concession as a conservation and retirement area. More extensive collecting in the wider area may reveal otherwise, but for now we must assume a small population size and a restricted distribution in Sumatera. While overall, undisturbed peat swamp forests have declined and under threat across Southeast Asia, and most remaining peatlands are converted to agriculture or degraded due to drainage (Miettinen et al. 2017; Page et al. 2022). Notes:— We have observed many trees in various life stages (seedling, sapling, pole to large tree) in the wild, and the pseudoverticillate leaves are consistent. Opposite (or subopposite) leaves as usually found in the genus but does not occur in this new species. On older branches we sometimes found opposite leaves but usually there is also a leaf scar slightly below them indicating they are not oppositely arranged from the beginning, but shift in position as the branchlets mature. If a twig is 3–4 angular depends on the number of leaves at a node, and this is clearly visible when the twigs are still young. The pseudoverticillate leaf arrangement of 3–4 leaves, and the associated 3–4 angular twigs, together with the retuse to emarginate leaf apex, and petiole with a pair of ridges to being conspicuously winged, comprise a unique set of vegetative characters for this species that have not been encountered in Lophopetalum previously, including all the species in Sumatera. Floral parts of L. tanahgambut superficially resemble L. rigidum Ridl. (Ridley 1931: 38), but can be differentiated by a combination of characters including its longer pedicels (4.0– 6.4 mm vs. 2–3 mm), larger flowers at anthesis (8.5–9.2 mm vs. 3.5–6.0 mm), different shape, dimension and size of calyx lobes (widely ovate, much wider than long, 1.1 × 2.2 mm, apex rounded vs. ovate or triangular, longer than wide, 1.3–1.5 × 1.0 mm, apex acuminate), petals with conspicuous appendages on inner side (vs. naked), and disk convex, 4–5 mm diameter (vs. roughly flat, 1.5–3.5 mm); in addition, L. tanahgambut is a large tree found in Sumatera, while L. rigidum is a small tree (to c. 12 m tall) endemic to Borneo. In the key to Malesian Lophopetalum (Ding Hou 1962: 264), this species would key out to the group of species having short conical flower buds with distinct appendages on the inner surfaces and having a disk greater than 4.5 mm in diameter: L. pachyphyllum King, L. wightianum Arn. and L. macranthum (Loes.) Ding Hou, with first two found in Sumatera and the latter species a New Guinea endemic. In addition to the unique leaf arrangement of L. tanahgambut, the new species differs from L. pachyphyllum and L. wightianum in the obscurely 5-angular disk rather than being distinctly lobed with the lobes or angle epipetalous, which is particularly pronounced and red to deep purple-red in L. wightianum. Of the other five taxa found in Sumatera, L. beccarianum Pierre, L. javanicum (Zoll.) Turcz., L. multinervium Ridl., L. pallidum M.A.Lawson and L. subobovatum King, in addition to the pseudoverticillate leaf arrangement, these species differ in the floral structure with L. beccarianum having flattened buds and the four other species all having a much smaller disk, usually less than 3 mm in diameter., Published as part of Randi, Agusti, Wijedasa, Lahiru S. & Utteridge, Timothy M. A., 2022, Lophopetalum tanahgambut, a new endemic giant tree species from peat swamp forest of Sumatera, Indonesia, with the first pseudoverticillate leaf arrangement in genus Lophopetalum (Celastraceae), pp. 115-122 in Phytotaxa 573 (1) on pages 116-120, DOI: 10.11646/phytotaxa.573.1.7, http://zenodo.org/record/7329561, {"references":["Wijedasa, L. S., Vernimmen, R., Page, S. E., Mulyadi, D., Bahri, S., Randi, A., Evans, T. A., Priatna, D., Jensen, R. M. & Hooijer, A. (2020) Distance to forest, mammal and bird dispersal drive natural regeneration on degraded tropical peatland. Forest Ecology and Management 461: 117868. https: // doi. org / 10.1016 / j. foreco. 2020.117868","IUCN Standards and Petitions Subcommittee (2019) Guidelines for using the IUCN Red List categories and criteria, version 14. Prepared by the Standards and Petitions Committee. [http: // www. iucnredlist. org / documents / RedListGuidelines. pdf]","Miettinen, J., Hooijer, A., Vernimmen, R., Liew, S. C. and Page, S. E. (2017) From carbon sink to carbon source: extensive peat oxidation in insular Southeast Asia since 1990. Environmental Research Letters 12 (2): 024014. https: // doi. org / 10.1088 / 1748 - 9326 / aa 5 b 6 f","Page, S., Mishra, S., Agus, F., Anshari, G., Dargie, G., Evers, S., Jauhiainen, J., Jaya, A., Jovani-Sancho, A. J., Lauren, A. and Sjogersten, S., Suspense, I. A., Wijedasa, L. S. & Evans, C. D. (2022) Anthropogenic impacts on lowland tropical peatland biogeochemistry. Nature Reviews Earth & Environment 3: 426 - 443. https: // doi. org / 10.1038 / s 43017 - 022 - 00289 - 6","Ridley, H. N. (1931) Additions to the Flora of Borneo and Other Malay Islands: II. Bulletin of miscellaneous information (Royal Gardens, Kew) 1931 (1): 33 - 39. https: // doi. org / 10.2307 / 4102587","Ding Hou (1962) Celastraceae - I. Fl. Males., Ser. I, Spermat. 6: 227 - 291."]}

Begonia kapuashuluensis Randi & Ardi, sp. nov., B. sect. Petermannia (Fig. 1). Type: ��� INDONESIA, West Kalimantan Province, Kapuas Hulu Regency, Boyan Tanjung District, 0��20'44.84"N, 112��25'4.53"E, 110 m elev., 10 July 2017, A . Randi AR-1022 (holotype BO!). Diagnosis:��� It is allied to B. darthvaderiana C.W.Lin & C.I Peng (Lin et al. 2014: 132) in habit and floral characters, but differs in being a smaller plant up to 20 cm (vs. 25���70 cm) height with smaller leaves 9���14 �� 4���7 cm (vs. 13���22 �� 8���13 cm), deep bluish green (vs. blackish green with a narrow pale margin) leaves, and more stamens (22���31 vs. 7���11). A small herb, erect, up to 20 cm tall. Stem with 1���3 branches, 4���7 mm in diameter at the base, glabrous, bright red to brownish, fleshy and succulent, internodes 1���3 cm apart. Stipules caducous, asymmetric, translucent, glabrous, elliptic to lanceolate, 10���15 �� 3���5 mm, with a stiff main rib and many parallel red veins; margin entire, apex acute with a short-pointed tip; pale green to red to brownish. Leaves 4���7, simple, alternate, oblique, glabrous; petiole 1���4 cm long, red to brownish, glabrous; lamina ovate, 9���14 �� 4���7 cm (basal lobes included); strongly asymmetric with a well-developed basal lobe on one side giving a cordate appearance, base unequal, basal lobes 1���3 cm long, margins minutely denticulate, generally with a narrow dark red border adaxially that is clearly visible on young leaves, apex acuminate; adaxially shiny, deep bluish-green, surface flat or slightly bullate, abaxially light red to crimson, glabrous; venation palmate-pinnate, midrib distinguishable, with 3���4 lateral veins each side, other primary veins branching dichotomously; young leaf brownish abaxially. Inflorescence protogynous, terminally or axillary, erect, 6���12 cm long; basal branch with a pair (rarely 2 pairs) of pistillate flowers on short peduncle ca. 1 cm long, often with leaves at the first branch; upper distal to 10 cm long, zig-zag, branching cymosely, peduncle to 5 cm long, cymes branching to 3 orders, crimson to brownish, glabrous; bracts caducous, translucent, glabrous; bract on nodes of pistillate flower elliptic to lanceolate ca. 5 �� 1 mm, cream to pinkish, margin entire, apex acute to cuspidate; bracts on higher part of inflorescence similar but smaller. Staminate flower with 2 pink tepals, each tepal ovate to orbicular or obovate, 3���5 �� 3���5 mm, glabrous, margin entire, apex acute to rounded; pedicel pink to crimson, 2���5 mm long, glabrous; androecium symmetric with 22���31 yellow stamens, filament 0.6���1.2 mm long, anthers obovate 0.7���1.4 mm long, apex opened by slit. Pistillate flower 10���20 mm across, each flower blooming alternately; pedicel pink to brownish red, 4���8 mm long, ca. 1 mm in diameter, glabrous; ovary 3-locular, asymmetric, 7���11 �� 10���15 mm (wings included), yellowish-green in the middle, red to brownish on the wings; tepals 5, glabrous, 2 outer and 3 inner, all pink and elliptic, 6���8 �� 4���5 mm, apex acute to obtuse; styles 3, bifid, 2���4 mm long, golden yellow; stigmas narrowly Y-shaped, forming a papillose spiral band. Fruits nodding, 7���15 �� 10���18 mm (wings included), pink to crimson, glabrous; wings 3, subequal, nearly parallel but with rounded, apex acute or mucronate, 3���4 mm wide at the widest point. Distribution: ���Endemic to Borneo, widespread in the western part of the Muller Mountains that administratively belong to Kapuas Hulu Regency of West Kalimantan Province, Indonesia. Habitat: ���Humid areas near rivers or narrow valleys under a dense canopy of mixed dipterocarp forest at 100��� 300 m elev. Etymology: ���The epithet refers to the name of regency where this species was found, Kapuas Hulu. Provisional Conservation Status: ���Near threatened (NT) (IUCN, 2019). This species is observed in seven localities and locally abundant in the western part of Muller Mountains. Although based on EOO = 184.6 km �� and AOO = 28 km �� this species potentially qualifies for the endangered category, but we have observed that this species is growing in relatively undisturbed forest and in several protected forest areas. However, the populations could be threatened due to extraction by plant hunters to be sold as an ornamental, as this beautiful species is well known among Begonia enthusiasts. It has the popular trade name Begonia ���temuyuk��� and is for sale on commercial and social media sites for prices ranging from 50 US dollars to 160 Euros. Traditional cultivation activity is also observed near the populations. In the future, these threats could drive the taxon to VU or even EN in a short time. Notes: ���Unlike most other erect species of Begonia sect. Petermannia in Borneo, B. kapuashuluensis has a very short stem not exceeding 20 cm tall. Apart from its small size, B. kapuashuluensis is distinctive in having deep bluish green leaves which are light red to crimson beneath, often with a small cauline leaf at the first branch of the inflorescence., Published as part of Randi, Agusti, Ardi, Wisnu H., Girmansyah, Deden, Sitepu, Bina Swasta & Hughes, Mark, 2022, Three new species, one new record and an updated checklist of Begonia (Begoniaceae) from Kalimantan, Indonesia, pp. 62-72 in Phytotaxa 533 (1) on page 63, DOI: 10.11646/phytotaxa.533.1.3, http://zenodo.org/record/5973875, {"references":["Lin, C. W., Chung, S. W. & Peng, C. - I. (2014) Three new species of Begonia (sect. Petermannia, Begoniaceae) from Sarawak, Borneo. Phytotaxa 191: 129 - 140. https: // doi. org / 10.11646 / phytotaxa. 191.1.8","IUCN Standards and Petitions Subcommittee (2019) Guidelines for Using the IUCN Red List Categories and Criteria. Version 14. Prepared by the Standards and Petitions Committee."]}

Begonia belagaensis S.Julia, Sandakania 20: 133 (2015). Type: ��� MALAYSIA, Borneo, Sarawak, Belaga District, Sungai Chak (Tributary of Sungai Murum), 20 March 2014, Ling et al. BMHEP 3821 (holotype SAR). (Fig. 4). Distribution:��� Endemic to Borneo. In Sarawak recorded in Belaga District, and in Kalimantan this species is recorded from Samboja Forest Research (KHDTK Samboja), Tahura Bukit Soeharto, and Sepaku area, Penajam Paser Utara. All localities are near Balikpapan City. It is also recorded from one location in Sungai Lokang, Kapuas Hulu Regency, West Kalimantan. Specimens examined:��� INDONESIA, East Kalimantan, Kutai Kartanegara, Samboja, 0 o 59���00���S, 116 o 56���10���E, 45 m elev., 28 March 2020, Sitepu & Randi BSS 650 (WAN); East Kalimantan, Penajam Paser Utara, 9 November 2019, Sitepu, BSS 602 (WAN); East Kalimantan, PT. ITCI, Kenangan, Balikpapan, 50 m elev., 5 March 1991, Ambriansyah & Arifin AA94 (WAN). Notes:��� Although there are some differences between the specimens found in Kalimantan and the description in Julia et al. (2015), the specimens from Kalimantan have larger leaves (8���25 �� 4���15 cm) and inflorescences bearing up to 6 pistillate flowers, the protologue describes smaller (12���12.5 �� 11.5���12 cm) leaves, and inflorescences bearing 1���2 pistillate flowers). However comparison with images in Kiew et al. (2015) and correspondence with the collector of the type confirm that both are same species. Distinctive characters for the species shared between material from Sarawak and Kalimantan are large clumping habit, glabrous in all parts, leaf shape and texture, glandular bracts and bracteole margins, petioles deeply channeled above, and morphology and colour of male and female flowers. The records from Kalimantan are abundant at altitudes ranging from 30���220 m elev., and in Sarawak it is only recorded at 540���560 m elev., Published as part of Randi, Agusti, Ardi, Wisnu H., Girmansyah, Deden, Sitepu, Bina Swasta & Hughes, Mark, 2022, Three new species, one new record and an updated checklist of Begonia (Begoniaceae) from Kalimantan, Indonesia, pp. 62-72 in Phytotaxa 533 (1) on pages 69-70, DOI: 10.11646/phytotaxa.533.1.3, http://zenodo.org/record/5973875, {"references":["Julia, S., Kiew, R. & Yiing, L. C. (2015) A decade of Begonia (Begoniaceae) from Borneo. Sandakania 20: 129 - 154.","Kiew, R., Sang, J., Repin, R. & Ahmad, J. A. (2015) A Guide to Begonias of Borneo. Natural History Publications (Borneo), Kota Kinabalu. 293 pp."]}

Begonia patar Randi, sp. nov. B. sect. Petermannia (Fig. 2). Type: ��� INDONESIA, West Kalimantan Province, Sintang Regency, Kelam Permai District, Ensaid Panjang Village, Bukit Rentab, 0��8���7.72���N, 111��43'56.65"E, 55 m elev., 19 October 2020, A . Randi AR-1051 (holotype BO!; isotype WAN!). Diagnosis:��� It is allied to B. kiamfeei Kiew & S.Julia (2007: 215) in having a creeping habit and hairy leaves, but differs in having larger (8���16 �� 6���12 cm vs. 6.5���8.5 �� 5���8.5 cm) variegated (vs. uniform green) leaves, and pistillate flowers in pairs (vs. single) per node. A short creeping herb. Stem stout, unbranched, 5���26 cm long, 4���8 mm in diameter, zig-zag, covered with villous hairs, succulent, pink to crimson; nodes with conspicuous leaf and stipule scars, internodes 4���19 mm apart. Stipules persistent, asymmetric, broadly ovate to broadly elliptic, 5���10 �� 4���8 mm, with conspicuous hairs on main rib abaxially, glabrous adaxially, margin entire, apex acute to obtuse to retuse, erect then becoming recurved with aging, greenish-yellow when fresh, usually pinkish at base. Leaves simple, alternate, oblique; petiole to 12 cm long, 1.5���3 mm in diameter, with villous or pilose hairs, pink to brownish red; lamina ovate, 8���16 �� 6���12 cm (basal lobes included), strongly asymmetric with overlap basal lobes, margins dentate when young then becoming crenate by age and undulated, often with thin red margin, apex obtuse, acute to caudate; adaxial surface variegated, dark green to purplish-brown with cream to light green on venations, completely covered by pilose hairs coloured white or pink to brownish red, abaxial surface very striking with a combination of pink to red with cream to light green on venations, with sparse and scattered pilose hairs; venation palmate-pinnate, midrib distinguishable, with 2���4 lateral veins each side, other primary veins branching dichotomously; young leaves brownish-red, completely covered by dense hairs adaxially and looser with age. Inflorescence protogynous, terminal then becoming opposite of leaves with aging, erect, up to 27 cm long, 2���4 mm diameter at the base, with sparse pilose hairs, roughly zig-zag for whole length, cream-pink to dark red; pistillate flowers placed ⅓ ��� ⅔ of inflorescence length from the base, to 4 flowers, a pair for each node, rarely solitary, to 5 cm apart, peduncle to 4.5 cm long; upper distal to 12 cm long, peduncle 1.5���3 cm long, cyme branching to 2 orders, pinkish to red; bracteoles caducous, broadly ovate, 3���6 �� 3���5 mm, margin entire, apex acute to obtuse to retuse, white or sometimes slightly pinkish, symmetric. Staminate flower with 4 tepals, 2 outer and 2 inner, glabrous; pedicel slender, 5���8 mm long, 0.5���1 mm diameter, glabrous; outer tepals broadly ovate to orbicular, 5.5���8 �� 6���7 mm, margin entire, apex rounded, white; inner tepals smaller than outer ones, elliptic to oblanceolate, 3.9���4.2 �� 1.8���2.2 mm, margin entire, apex acute to rounded, white; androecium symmetric, 3���4 mm long, with 38���40 yellow stamens, filament 0.2���1 mm long, anthers obovate, 0.8���1.2 �� 0.5���0.8 mm, with divided apex, opened by slit. Pistillate flower at anthesis phase 13���20 mm across; pedicel ca. 10 mm long, ca. 1 mm diameter, white to pale pink, glabrous; ovary 3-locular, asymmetric or sometimes symmetric, 7���9 �� 12���14 mm (wings included), white, pale pink to pale purple; tepals 5, glabrous, 2 outer and 3 inner; outer tepals broadly ovate to orbicular, 6.5���7 �� 7 mm, margin entire, apex broadly acute to rounded, white or sometimes pinkish at base; inner tepals with 2 broader and 1 smaller, broader ones broadly elliptic to suborbicular, 6���7.5 �� 5���6.5 mm, apex broadly acute to rounded, white or sometimes pinkish at base, smaller one elliptic or obovate, ca. 5.5 �� 3 mm, apex acute to obtuse to rounded, white; styles 3, ca. 3 mm long, bifid, pale to golden yellow; stigmas anchor-shaped, forming a short papillose spiral band. Fruit nodding, 6���15 �� 8���18 mm (wings included), green to pink with dark red wings, glabrous; wings 3, subequal, often curved sideways, apex rounded, 3���6 mm wide at the widest point. Ecology:��� Creeping on vertical granite rocks at 50���100 m elev. This species grows directly on the surface of granite rocks or on the surface of thin mosses with medium light intensity. Distribution:��� Endemic to Borneo, so far it has only been found in Bukit Rentab, Ensaid Panjang Village, Sintang Regency, West Kalimantan. Etymology: ���The epithet of this species is derived from the local name patar, which means patterned from the Dayak Desa language, referring to the colour variation of the leaves. Provisional Conservation Status:��� Critically endangered (CR) B1ab(iii) + B2ab(iii) (IUCN, 2019). This species is found on a single small hill and is limited to rocky cliffs at the foot of the hill on the south side. Three subpopulations were found in the area with an EOO of 0.01 km �� and AOO of 4 km �� only. The habitat of the population is very easy to reach, and the distribution area is also a tourist location that is free to be entered by anyone. Although the habitat is a protected forest, forest fires have occurred several times in this location and shifting cultivation activities of local communities are still very active in the area. The population could also be threatened due to collection by plant hunters for use as ornamental plants. These threats can push this species towards possible extinction in a short time if there is no conservation effort. Therefore, ex-situ conservation of this species is urgently needed. Uses:��� The Dayak Desa people who live in the longhouse of Ensaid Panjang Sintang use it as a mixture of traditional ingredients to protect women after childbirth and their babies from demonic disturbances, besides that it is also used as a traditional herb to treat headaches. Notes:��� Begonia patar has a stout stem, 5���26 cm long and short internodes 0.4���1.9 cm apart, in contrast to B. kiamfeei which has a much more slender stem up to 50 cm long and internodes 2.5���4.5 cm long. The leaves of B. patar are distinctly variegated with a combination of dark green to purplish-brown with cream to light green on the venation adaxially and pink to red with cream to light green on the venation abaxially, while B. kiamfeei leaves are mid-green with pale green veins adaxially and paler beneath. The pistillate flowers of B. patar are in groups of up to 4 flowers, in a pair for each node, inner tepals 3 with 2 large and one smaller tepal in between, while B. kiamfeei bears up to 6 flowers which are solitary at each node, inner tepals 3 of the same size and shape. The habitat of the two species is also different, as B. patar grows on granite rocks, while B. kiamfeei grows on limestone. The habit, and attractive variegated ovate leaves of B. patar are also superficially similar to B. conipila Irmsch. ex Kiew (2001a: 287), however it has pale veins on a dark background, whereas B. conipila has dark veins on a pale background. In addition, some key characters are distinctive like the stipules broadly ovate to broadly elliptic in B. patar, while lanceolate in B. conipila. The petiole of B. patar is much longer (up to 12 cm long vs. to 5 cm) compared with B. conipila. Inflorescence in B. patar is terminal then becoming opposite to the leaves with ageing, up to 27 cm long, with two pairs of pistillate flowers at ⅓ ��� ⅔ of inflorescence length from the base, whereas B. conipila has axillary inflorescences, up to 9.5 cm long, with a single basal pistillate flower. The number of stamens is 38���40 in B. patar, and 10���11 in B. conipila. Their habitats are also very different, as B. patar grows on vertical granite rocks to 100 m elev., and B. conipila grows on limestone to ca. 1170 m elev., Published as part of Randi, Agusti, Ardi, Wisnu H., Girmansyah, Deden, Sitepu, Bina Swasta & Hughes, Mark, 2022, Three new species, one new record and an updated checklist of Begonia (Begoniaceae) from Kalimantan, Indonesia, pp. 62-72 in Phytotaxa 533 (1) on pages 65-67, DOI: 10.11646/phytotaxa.533.1.3, http://zenodo.org/record/5973875, {"references":["IUCN Standards and Petitions Subcommittee (2019) Guidelines for Using the IUCN Red List Categories and Criteria. Version 14. Prepared by the Standards and Petitions Committee.","Kiew, R. (2001 a) Begonia conipila Irmsch. ex Kiew (Begoniaceae) from the Gunung Mulu National Park, Sarawak, Malaysia. Gardens' Bulletin Singapore 53: 287 - 289."]}

Begonia kapuashuluensis Randi & Ardi, sp. nov., B. sect. Petermannia (Fig. 1). Type: — INDONESIA, West Kalimantan Province, Kapuas Hulu Regency, Boyan Tanjung District, 0°20'44.84"N, 112°25'4.53"E, 110 m elev., 10 July 2017, A . Randi AR-1022 (holotype BO!). Diagnosis:— It is allied to B. darthvaderiana C.W.Lin & C.I Peng (Lin et al. 2014: 132) in habit and floral characters, but differs in being a smaller plant up to 20 cm (vs. 25–70 cm) height with smaller leaves 9–14 × 4–7 cm (vs. 13–22 × 8–13 cm), deep bluish green (vs. blackish green with a narrow pale margin) leaves, and more stamens (22–31 vs. 7–11). A small herb, erect, up to 20 cm tall. Stem with 1–3 branches, 4–7 mm in diameter at the base, glabrous, bright red to brownish, fleshy and succulent, internodes 1–3 cm apart. Stipules caducous, asymmetric, translucent, glabrous, elliptic to lanceolate, 10–15 × 3–5 mm, with a stiff main rib and many parallel red veins; margin entire, apex acute with a short-pointed tip; pale green to red to brownish. Leaves 4–7, simple, alternate, oblique, glabrous; petiole 1–4 cm long, red to brownish, glabrous; lamina ovate, 9–14 × 4–7 cm (basal lobes included); strongly asymmetric with a well-developed basal lobe on one side giving a cordate appearance, base unequal, basal lobes 1–3 cm long, margins minutely denticulate, generally with a narrow dark red border adaxially that is clearly visible on young leaves, apex acuminate; adaxially shiny, deep bluish-green, surface flat or slightly bullate, abaxially light red to crimson, glabrous; venation palmate-pinnate, midrib distinguishable, with 3–4 lateral veins each side, other primary veins branching dichotomously; young leaf brownish abaxially. Inflorescence protogynous, terminally or axillary, erect, 6–12 cm long; basal branch with a pair (rarely 2 pairs) of pistillate flowers on short peduncle ca. 1 cm long, often with leaves at the first branch; upper distal to 10 cm long, zig-zag, branching cymosely, peduncle to 5 cm long, cymes branching to 3 orders, crimson to brownish, glabrous; bracts caducous, translucent, glabrous; bract on nodes of pistillate flower elliptic to lanceolate ca. 5 × 1 mm, cream to pinkish, margin entire, apex acute to cuspidate; bracts on higher part of inflorescence similar but smaller. Staminate flower with 2 pink tepals, each tepal ovate to orbicular or obovate, 3–5 × 3–5 mm, glabrous, margin entire, apex acute to rounded; pedicel pink to crimson, 2–5 mm long, glabrous; androecium symmetric with 22–31 yellow stamens, filament 0.6–1.2 mm long, anthers obovate 0.7–1.4 mm long, apex opened by slit. Pistillate flower 10–20 mm across, each flower blooming alternately; pedicel pink to brownish red, 4–8 mm long, ca. 1 mm in diameter, glabrous; ovary 3-locular, asymmetric, 7–11 × 10–15 mm (wings included), yellowish-green in the middle, red to brownish on the wings; tepals 5, glabrous, 2 outer and 3 inner, all pink and elliptic, 6–8 × 4–5 mm, apex acute to obtuse; styles 3, bifid, 2–4 mm long, golden yellow; stigmas narrowly Y-shaped, forming a papillose spiral band. Fruits nodding, 7–15 × 10–18 mm (wings included), pink to crimson, glabrous; wings 3, subequal, nearly parallel but with rounded, apex acute or mucronate, 3–4 mm wide at the widest point. Distribution: —Endemic to Borneo, widespread in the western part of the Muller Mountains that administratively belong to Kapuas Hulu Regency of West Kalimantan Province, Indonesia. Habitat: —Humid areas near rivers or narrow valleys under a dense canopy of mixed dipterocarp forest at 100– 300 m elev. Etymology: —The epithet refers to the name of regency where this species was found, Kapuas Hulu. Provisional Conservation Status: —Near threatened (NT) (IUCN, 2019). This species is observed in seven localities and locally abundant in the western part of Muller Mountains. Although based on EOO = 184.6 km ² and AOO = 28 km ² this species potentially qualifies for the endangered category, but we have observed that this species is growing in relatively undisturbed forest and in several protected forest areas. However, the populations could be threatened due to extraction by plant hunters to be sold as an ornamental, as this beautiful species is well known among Begonia enthusiasts. It has the popular trade name Begonia “temuyuk” and is for sale on commercial and social media sites for prices ranging from 50 US dollars to 160 Euros. Traditional cultivation activity is also observed near the populations. In the future, these threats could drive the taxon to VU or even EN in a short time. Notes: —Unlike most other erect species of Begonia sect. Petermannia in Borneo, B. kapuashuluensis has a very short stem not exceeding 20 cm tall. Apart from its small size, B. kapuashuluensis is distinctive in having deep bluish green leaves which are light red to crimson beneath, often with a small cauline leaf at the first branch of the inflorescence.

Begonia sangkulirangensis Ardi, Girm. & Randi, sp. nov. B. sect. Petermannia (Fig. 3). Type:��� INDONESIA, East Kalimantan Province, Karst Sangkulirang, Bengalon, Goa Tewet Trail, 1��3���47.9���N, 117��16���11.4���E, ca. 80 m elev. (cultivated at Bogor Botanic Garden from material collected in the wild (Hughes M., Girmansyah D., Yeats H. & Ardiyani M. EKBOE138), 4 December 2019, Wisnu H. Ardi WI 684 (holotype BO!). Diagnosis:��� The erect habit and peltate leaves of B. sangkulirangensis are similar to B. nothobaramensis Joffre (2015: 35) from Brunei but it can be easily distinguished by its shorter (50���60 cm vs. 100 cm) habit, smaller (7���12 �� 3.5���5.5 cm vs. 9.5���18 �� 5���9 cm) lamina, more (45���55 vs. ca. 36) stamens, female inflorescence consistently with a single (vs. two) flower on a shorter (10���13 mm vs. 17���20 mm) pedicel, ovary wing shape cuneate (vs. rounded) at the base and apex. Begonia sangkulirangensis also differs from both B. baramensis and B. nothobaramensis in having a thicker and more succulent leaf lamina. An erect herb, up to ca. 50 cm tall. Stem branched, nearly glabrous except for moderate microscopic glandular hairs, reddish-brown, internodes 2���9 cm apart. Stipules caducous, glabrous, elliptic, 6���8 �� 2���4 mm, midrib prominent, margin entire, translucent, apex narrowed into bristle up to 1.5 mm long; whitish-greenish. Leaves simple, alternate, glabrous; petioles 2���5 cm long, concolourous with the stem, terete; lamina peltate, coriaceous, elliptic, 7���12 �� 3.5���5.5 cm, asymmetric, apex acuminate, margin subentire, serrate from the middle part upward to the apex, adaxial surface dark green with brownish veins, abaxial surface pale green, veins reddish to brownish; venation palmate-pinnate, primary veins 5���6, actinodromous, secondary veins craspedodromous.Inflorescence protogynous; female inflorescence solitary, one node basal to male inflorescence or further separated, peduncle 3���5 mm long, reddish-green, glabrous, bracteoles minute, hairlike, persistent; upper distal that bearing male inflorescence paniculate, composed of up to 4 simple monochasium with 4���7 flowers, peduncle 5���8 mm long, glabrous; bracts stipule-like, persistent, ovate, ca. 4 �� 1.5 mm, translucent, midrib slightly prominent, pale green, glabrous, apex acuminate and narrowed into bristle ca. 1 mm long; bracteoles persistent, minute. Staminate flower pedicel up to 7.5 mm long, whitish-green, glabrous; tepals 2, broadly ovate, 4���6 �� 5���7 mm, greenish-red or dull cream, glabrous, margin entire, apex rounded; androecium symmetric with 48���55 yellow stamens, filaments up to ca. 1 mm long, fused at the base, anthers ca. 0.5 mm long, dehiscing through unilaterally positioned slits ca. �� as long as the anthers. Pistillate flowers: pedicels 10���13 mm long, pale green, glabrous; ovary 3-locular, cylindrical, 16���18 �� 2���3 mm (wings excluded), pale green, glabrous, placentae bilamellate, wings 3, subequal, base cuneate to rounded, apex subcuneate, widest point up to 7 mm (1 / 3 from the apex); tepals 5, glabrous, white tinged with pink and green, unequal, one smaller elliptic, 5���6 �� 2���3 mm, the four larger ovate, 8���9 �� 4.5���6 mm, margin entire, apex rounded; style ca. 4.5 mm long, basally fused, 3-branched, each stylodium bifurcate in the stigmatic region, stigmatic surface a spirally twisted papillose band, orange. Fruit peduncle up to 5 mm long; pedicels up to 15 mm long, pendulous and recurved; seed-bearing part cylindrical, 16���19 �� 3���4 mm (wings excluded), wing shape as for ovary, widest point up to ca. 8 mm. Seeds barrel-shaped, 0.2���0.3 mm long. Distribution: ���Endemic to Borneo, so far only known from the type locality in the Sangkulirang-Mangkalihat Limestone Karst Ecosystem, East Kalimantan Province, Indonesia. Habitat:��� This species was found on a limestone cliff in a shallow cave in deep shade beneath scrubby karst vegetation. It was growing in thin dusty soil on a slightly damp mossy rock. Etymology:��� The epithet refers to the name of Sangkulirang, the Limestone Karst Mountain Ecosystem where this species was found. Provisional Conservation Status:��� Vulnerable (VU, D2). This species is only known from single collection from the Sangkulirang Mangkalihat Limestone Karst Ecosystem. The area does not yet have legal protected status, and there are clear signs of anthropogenic disturbance (oil palm plantations and mining) around the karst formations. As a karst micro-endemic it therefore is ���prone to the effects of human activities or stochastic events within a very short time period in an uncertain future��� (IUCN Standards and Petitions Subcommittee 2019). An ex-situ initiative has been started with plants being cultivated at Kebun Raya Bogor (Bogor Botanic Garden). Notes: ���There are four other caulescent species in B. sect. Petermannia in Borneo with conspicuously peltate leaves: B. amphioxus Sands (1990: 81), B. baramensis Merrill (1928: 529) B. layang-layang Kiew (2001b: 272) and B. nothobaramensis Joffre (2015: 35). Begonia sangkulirangensis is closest to B. nothobaramensis as discussed in the diagnosis above, and B. baramensis is a much larger plant, reaching up to 3 m tall (Kiew et al. 2015). Begonia amphioxus and B. layang-layang do not appear to be closely allied, both differing most obviously in their leaves which are acute at the base and tip., Published as part of Randi, Agusti, Ardi, Wisnu H., Girmansyah, Deden, Sitepu, Bina Swasta & Hughes, Mark, 2022, Three new species, one new record and an updated checklist of Begonia (Begoniaceae) from Kalimantan, Indonesia, pp. 62-72 in Phytotaxa 533 (1) on pages 67-69, DOI: 10.11646/phytotaxa.533.1.3, http://zenodo.org/record/5973875, {"references":["Joffre, A. A., Kiew, R., Julia, S. & Repin, R. (2015) The Begoniaceae of Brunei Darussalam, Borneo, including two new species. Sandakania 20: 7 - 50.","IUCN Standards and Petitions Subcommittee (2019) Guidelines for Using the IUCN Red List Categories and Criteria. Version 14. Prepared by the Standards and Petitions Committee.","Sands, M. J. S. (1990) Six new Begonias from Sabah. Kew Magazine 7: 57 - 85.","Merrill, E. D. (1928) A collection of plants from Sarawak. Sarawak Museum Journal 3: 513 - 557.","Kiew, R. (2001 b) The limestone Begonias of Sabah, Borneo - flagship species for conservation. Gardens' Bulletin Singapore 53: 241 - 268.","Kiew, R., Sang, J., Repin, R. & Ahmad, J. A. (2015) A Guide to Begonias of Borneo. Natural History Publications (Borneo), Kota Kinabalu. 293 pp."]}

Key to the Disepalum species of Sumatra 1. Corolla lobes 5���9, as wide as or wider than long...................................................................................................... D. platypetalum - Corolla lobes 4, longer than wide.......................................................................................................................................................2 2. Corolla lobes linear and of uniform thickness, with acute apex, to 4.5 mm wide at the base........................... D. acuminatissimum - Corolla lobes spatulate, slightly thickened towards the blunt apex, less than 2 mm wide at the base...............................................3 3. Sepals 6.5���10.5 �� 5.5���8.0 mm; carpophores 2.2���4.0 cm long, 0.8���1.5 mm thick, monocarps 9.0���13.0 �� 7.5���10.0 mm; small tree to 8 m tall in upland and hill forests at 600���1200 m......................................................................................................... D. longipes - Sepals 10.0���16.0 �� 8.0���14.0 mm; carpophores 4.0��� 8.6 cm long, 2.0���6.0 mm thick, monocarps 10���21 �� 6���15 mm; medium-sized trees to 25 m tall in lowland peat swamp forest......................................................................................................... D. rawagambut, Published as part of Randi, Agusti, Wijedasa, Lahiru S. & Thomas, Daniel C., 2022, Disepalum rawagambut (Annonaceae), a new tree species from peat swamp forest of Sumatra, Indonesia, pp. 121-126 in Phytotaxa 530 (1) on page 125, DOI: 10.11646/phytotaxa.530.1.14, http://zenodo.org/record/5823886

Disepalum rawagambut Randi, D.C.Thomas & Wijedasa, sp. nov. (Figs 1���2). Type:��� INDONESIA. South Sumatera Province: Musi Banyuasin Regency, Bayung Lencir District, Muara Medak Village, conservation area of PT Tri Pupajaya forest production concession, 10 m. elev., 1��46���14.52���S, 104��12���6.82���E, 30 Nov 2020, Randi GB-035 (holotype: BO; isotypes: WAN, FIPIA, SING). Disepalum rawagambut has flowers with two sepals and four relatively short, spatulate corolla lobes that are thickened in the distal part with blunt apices similar to those of D. anomalum (Borneo) and D. longipes (Malay Peninsula, Sumatra). The new species can be differentiated by a combination of characters including its habit, large sepals, smaller corolla lobes and larger fruit (larger torus, longer carpophores, and larger monocarps; Table 1). Medium-sized tree to 25 m tall and to 28 cm DBH; monopodial, lateral branches almost horizontal; stilt roots often present on older trees. Bark rough, irregularly cracked to scaly and peeling off, dull to dark brown with grey-white patches; inner bark pale brown to chocolate; sapwood cream to pinkish; bark at the sapling stage smooth or shallowly cracked and often with conspicuous horizontal lines. Leafless twigs cylindrical with conspicuous and persistent petiole scars; leafy portion of the twigs 2���5 mm thick with a conspicuous raised edge adaxially, glabrous, green to shiny brown with age. Leaves simple, alternate, coriaceous, elliptic or sometimes lanceolate or oblanceolate, 3.0���12.0 �� 1.7���6.0 cm; base cuneate to shortly decurrent; margin entire, slightly thickened at the base and minutely recurved; apex bend downwards, acute to shortly acuminate, acumen 2���8 mm long, apex blunt; adaxial surface green, glabrous, abaxial surface pale green, puberulent and appressed pubescent on the midrib, glabrescent; midrib sunken adaxially, raised abaxially; secondary veins slender, 7���10 pairs, brochidodromous, visible adaxially and indistinct abaxially when fresh; tertiary venation widely reticulate, slightly raised and visible on adaxial surface when fresh, slightly sunken and indistinct abaxially. Petiole 4���9 mm long, channeled adaxially, glabrous, green to pink or pale brown when fresh. Flowers solitary or rarely in a 2-flowered inflorescence, borne terminally, or sometimes leaf-opposed with the opposing leaf reduced in size; 2-flowered inflorescence a fan-shaped cyme (rhipidium), peduncle and internodes ca. 1���2 mm long, bracts 12���23 �� 4���12 mm, oblanceolate to narrowly oblanceolate, with scattered simple hairs on both surfaces, caducous; pedicel 4.1���7.5 �� 1.2���2.5 mm, with scattered, appressed hairs, pink to pale brown when fresh, rarely green. Sepals 2, broadly obovate or broadly elliptic, 10���16 �� 8���14 mm, boat-shaped or flat when young and becoming boat-shaped with age, coriaceous, apex obtuse, adaxial surface glabrous or rarely puberulous, light green and sometimes pinkish to dull brown in the basal part, abaxial surface with scattered appressed hairs, green to crimson. Petals connate, corolla tube 5���11 mm long, obconical, slightly thickened at the base, adnate to torus, dark red to blackish at the base, distally greenish, distal half of tube pubescent with appressed hairs abaxially; corolla lobes 4, greenish yellow to brownish yellow, spatulate, wider and thicker at apex, strongly incurved, 2.0���4.0 �� 0.8���1.2 mm at the widest point, apex rounded, appressed pubescent on both surfaces; stamens numerous, 1.7���2.2 mm long, connective extending beyond the pollen sacs at the apex, apex nearly flat to rounded, puberulent; carpels numerous (to 170), ovules (1���)2 per carpel, ovaries 0.4���0.9 mm long, surface glabrous or puberulent with appressed hairs and with long-erect hairs at the base, style and stigma oblong, 0.8���1.2 mm long, setulose. Pedicel in fruiting stage 4.5���10.0 cm long, 3.5���8.0 mm thick, woody, glabrous, light to pale brown. Sepals persistent in fruit, yellow and then drying pale to dark brown. Torus in fruiting stage 2.0��� 3.5 cm in diameter; carpophores (10���) 40���86 mm long, 2���6 mm thick, thickest at the apex, dark red when fresh. Monocarps (22���)56���142, ovoid to ellipsoid, 10���21 �� 6���15 mm, base rounded, apex rounded or apiculate, the surface often foveate, glabrous; immature monocarps red, turning shiny black when ripe; pericarp 1���2 mm wide, juicy, deep purple to blackish when fresh. Seeds 2, rarely 1, flattened-ellipsoid, 6.2���11.0 �� 4.0���9.0 mm, light to dark brown with clearly visible grooves on the surface when fresh. Distribution:��� So far only known from the type locality. However, a wider distribution seems likely given the wide distribution of suitable peat swamp forest habitat along the east coast of Sumatra. Ecology and phenology:��� Intact peat swamp forest with soil conditions that are always wet to flooded. Growing scattered in relatively undisturbed forest, D. rawagambut is uncommon at the type location. Only two mature individuals were found within a two-hectare plot, and no seedlings were observed in the vicinity of the mature trees. Although rare, some seedlings were observed in regenerated peat swamp forest not far from the intact forest. Flowering and fruiting March���April and October���November. The fruits were observed to be eaten by hornbills, and fallen fruits are eaten by terrestrial mammals like wild boars and mouse deer. Etymology:��� The species epithet refers to the specific habitat of the new species in Bahasa Indonesia: rawa gambut (peat swamp). Vernacular name: ��� Pisang-pisang (Palembang Malay); this vernacular name is also applied to other Annonaceae species. Provisional conservation status assessment:��� Critically endangered: CR C2a(i) (IUCN 2019). Disepalum rawagambut grows in relatively undisturbed lowland peat swamp forest, which is protected by mandatory regulations for private forestry concessions. More extensive collecting in the wider area may reveal otherwise, but for now we must assume a small populations size and a restricted distribution in Sumatra. Threats from active illegal logging operations and forest fires in the area surrounding the type location were observed. Uses:��� Local use for machete handles and firewood. Notes:��� Morphologically, D. rawagambut is most similar to D. longipes, but apart from morphological differences (Table 1), this species prefers forests at 600���1200 m in Sumatra, whereas D. rawagambut is a lowland peat swamp species., Published as part of Randi, Agusti, Wijedasa, Lahiru S. & Thomas, Daniel C., 2022, Disepalum rawagambut (Annonaceae), a new tree species from peat swamp forest of Sumatra, Indonesia, pp. 121-126 in Phytotaxa 530 (1) on pages 121-125, DOI: 10.11646/phytotaxa.530.1.14, http://zenodo.org/record/5823886, {"references":["Johnson, D. M. (1989) Revision of Disepalum (Annonaceae). Brittonia 41: 356 - 378. https: // doi. org / 10.2307 / 2807547","Turner, I., Weerasooriya, A. D., Saunders, R. M. K. & Ganesan, S. K. (2014) Annonaceae. In: Soepadmo, E., Saw, L. G., Chung, R. C. K. & Kiew, R. (Eds.) Tree flora of Sabah and Sarawak, vol. 8. Forest Research Institute Malaysia, Kepong, pp. 1 - 200. https: // doi. org / 10.26525 / TFSS 8001","IUCN Standards and Petitions Subcommittee (2019) Guidelines for using the IUCN Red List categories and criteria, version 14. Prepared by the Standards and Petitions Committee. [http: // www. iucnredlist. org / documents / RedListGuidelines. pdf]"]}

Disepalum rawagambut Randi, D.C.Thomas & Wijedasa, sp. nov. (Figs 1–2). Type:— INDONESIA. South Sumatera Province: Musi Banyuasin Regency, Bayung Lencir District, Muara Medak Village, conservation area of PT Tri Pupajaya forest production concession, 10 m. elev., 1°46’14.52”S, 104°12’6.82”E, 30 Nov 2020, Randi GB-035 (holotype: BO; isotypes: WAN, FIPIA, SING). Disepalum rawagambut has flowers with two sepals and four relatively short, spatulate corolla lobes that are thickened in the distal part with blunt apices similar to those of D. anomalum (Borneo) and D. longipes (Malay Peninsula, Sumatra). The new species can be differentiated by a combination of characters including its habit, large sepals, smaller corolla lobes and larger fruit (larger torus, longer carpophores, and larger monocarps; Table 1). Medium-sized tree to 25 m tall and to 28 cm DBH; monopodial, lateral branches almost horizontal; stilt roots often present on older trees. Bark rough, irregularly cracked to scaly and peeling off, dull to dark brown with grey-white patches; inner bark pale brown to chocolate; sapwood cream to pinkish; bark at the sapling stage smooth or shallowly cracked and often with conspicuous horizontal lines. Leafless twigs cylindrical with conspicuous and persistent petiole scars; leafy portion of the twigs 2–5 mm thick with a conspicuous raised edge adaxially, glabrous, green to shiny brown with age. Leaves simple, alternate, coriaceous, elliptic or sometimes lanceolate or oblanceolate, 3.0–12.0 × 1.7–6.0 cm; base cuneate to shortly decurrent; margin entire, slightly thickened at the base and minutely recurved; apex bend downwards, acute to shortly acuminate, acumen 2–8 mm long, apex blunt; adaxial surface green, glabrous, abaxial surface pale green, puberulent and appressed pubescent on the midrib, glabrescent; midrib sunken adaxially, raised abaxially; secondary veins slender, 7–10 pairs, brochidodromous, visible adaxially and indistinct abaxially when fresh; tertiary venation widely reticulate, slightly raised and visible on adaxial surface when fresh, slightly sunken and indistinct abaxially. Petiole 4–9 mm long, channeled adaxially, glabrous, green to pink or pale brown when fresh. Flowers solitary or rarely in a 2-flowered inflorescence, borne terminally, or sometimes leaf-opposed with the opposing leaf reduced in size; 2-flowered inflorescence a fan-shaped cyme (rhipidium), peduncle and internodes ca. 1–2 mm long, bracts 12–23 × 4–12 mm, oblanceolate to narrowly oblanceolate, with scattered simple hairs on both surfaces, caducous; pedicel 4.1–7.5 × 1.2–2.5 mm, with scattered, appressed hairs, pink to pale brown when fresh, rarely green. Sepals 2, broadly obovate or broadly elliptic, 10–16 × 8–14 mm, boat-shaped or flat when young and becoming boat-shaped with age, coriaceous, apex obtuse, adaxial surface glabrous or rarely puberulous, light green and sometimes pinkish to dull brown in the basal part, abaxial surface with scattered appressed hairs, green to crimson. Petals connate, corolla tube 5–11 mm long, obconical, slightly thickened at the base, adnate to torus, dark red to blackish at the base, distally greenish, distal half of tube pubescent with appressed hairs abaxially; corolla lobes 4, greenish yellow to brownish yellow, spatulate, wider and thicker at apex, strongly incurved, 2.0–4.0 × 0.8–1.2 mm at the widest point, apex rounded, appressed pubescent on both surfaces; stamens numerous, 1.7–2.2 mm long, connective extending beyond the pollen sacs at the apex, apex nearly flat to rounded, puberulent; carpels numerous (to 170), ovules (1–)2 per carpel, ovaries 0.4–0.9 mm long, surface glabrous or puberulent with appressed hairs and with long-erect hairs at the base, style and stigma oblong, 0.8–1.2 mm long, setulose. Pedicel in fruiting stage 4.5–10.0 cm long, 3.5–8.0 mm thick, woody, glabrous, light to pale brown. Sepals persistent in fruit, yellow and then drying pale to dark brown. Torus in fruiting stage 2.0– 3.5 cm in diameter; carpophores (10–) 40–86 mm long, 2–6 mm thick, thickest at the apex, dark red when fresh. Monocarps (22–)56–142, ovoid to ellipsoid, 10–21 × 6–15 mm, base rounded, apex rounded or apiculate, the surface often foveate, glabrous; immature monocarps red, turning shiny black when ripe; pericarp 1–2 mm wide, juicy, deep purple to blackish when fresh. Seeds 2, rarely 1, flattened-ellipsoid, 6.2–11.0 × 4.0–9.0 mm, light to dark brown with clearly visible grooves on the surface when fresh. Distribution:— So far only known from the type locality. However, a wider distribution seems likely given the wide distribution of suitable peat swamp forest habitat along the east coast of Sumatra. Ecology and phenology:— Intact peat swamp forest with soil conditions that are always wet to flooded. Growing scattered in relatively undisturbed forest, D. rawagambut is uncommon at the type location. Only two mature individuals were found within a two-hectare plot, and no seedlings were observed in the vicinity of the mature trees. Although rare, some seedlings were observed in regenerated peat swamp forest not far from the intact forest. Flowering and fruiting March–April and October–November. The fruits were observed to be eaten by hornbills, and fallen fruits are eaten by terrestrial mammals like wild boars and mouse deer. Etymology:— The species epithet refers to the specific habitat of the new species in Bahasa Indonesia: rawa gambut (peat swamp). Vernacular name: — Pisang-pisang (Palembang Malay); this vernacular name is also applied to other Annonaceae species. Provisional conservation status assessment:— Critically endangered: CR C2a(i) (IUCN 2019). Disepalum rawagambut grows in relatively undisturbed lowland peat swamp forest, which is protected by mandatory regulations for private forestry concessions. More extensive collecting in the wider area may reveal otherwise, but for now we must assume a small populations size and a restricted distribution in Sumatra. Threats from active illegal logging operations and forest fires in the area surrounding the type location were observed. Uses:— Local use for machete handles and firewood. Notes:— Morphologically, D. rawagambut is most similar to D. longipes, but apart from morphological differences (Table 1), this species prefers forests at 600–1200 m in Sumatra, whereas D. rawagambut is a lowland peat swamp species.