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Blumea 55, 2010: 189–195 www.ingentaconnect.com/content/nhn/blumea RESEARCH ARTICLE doi:10.3767/000651910X527699 Three new species and a new name in Southeast Asian Gomphandra (Stemonuraceae / Icacinaceae s.l.) M. Schori1, T.M.A. Utteridge2 Key words Abstract Three new species of Gomphandra (Stemonuraceae / Icacinaceae s.l.) are described from Malesia, and a new name is proposed for a misidentified species. Gomphandra palustris is known from peat swamp forests Gomphandra in Borneo, Sarawak, G. halconensis is known from the Philippines, Mindoro, Mt Halcon, and G. conklinii from the Icacinaceae Philippines, Ifugao Province, Banaue. Gomphandra rarinervis is offered as a new name for Stemonurus puberulus, new species which was incorrectly synonymised with G. papuana by Sleumer. This commonly collected taxon is known from Southeast Asia Madang and Morobe Provinces in Papua New Guinea and does not overlap in distribution with G. papuana. Stemonuraceae Stemonurus Published on 20 August 2010 INTRODUCTION Gomphandra Wall. ex Lindl. is a genus of approximately 65 species of small trees and shrubs distributed from Sri Lanka and India to China, Indo-China, and throughout Southeast Asia to the Solomon Islands. The genus was revised by Sleumer in 1969 prior to its inclusion in Flora Malesiana (Sleumer 1971). Although it was traditionally placed in Icacinaceae, Kårehed (2001) provided evidence that the family is polyphyletic and placed Gomphandra in the segregate family Stemonuraceae. Gomphandra is the largest genus in the family, with 33 species previously recognized (Sleumer 1969) and approximately 30 new taxa. The genus is characterized by functionally dioecious flowers, a large sessile stigma, and fruit with longitudinal inner mesocarp ridges. Other genera in the family that share these characteristics also have laterally compressed fruit, usually with a fleshy lateral appendage, both of which are absent in Gom- a phandra. The site of appendage attachment may correspond to a distinctive pair of ridges and grooves flanking a central ridge on one side of the inner mesocarp in Gomphandra, a feature we refer to as a sulcus because the immediate impression is of a b groove on the inner mesocarp (Fig. 1). The term ‘pseudohilum’ Fig. 1 Sulcus. a. The stigma is displaced toward a pair of parallel grooves was considered for this feature, but it has already been used (emphasized here as thick black lines) divided by a ridge, all of which is here referred to as a sulcus. The longitudinal ribs of the inner mesocarp are to refer to a feature of the seeds of Sapindaceae (Weckerle & visible to either side; b. sulcus in profile. The thick black bars correspond to Rutishauser 2005). The sulcus is not visible in fresh fruit but can the thick lines shown in the lateral view. The ridges and grooves of the sulcus be pronounced on dried mature fruits, though the ridges vary are not more prominent than those of the longitudinal ridges in this species in prominence depending upon the species. Sleumer (1971) (G. luzoniensis, Reynoso et al. PPI 17155). — Scale bars = 1 cm. and others referred to the endocarp being ridged, but the ridges represent sclerified bundles of the inner mesocarp. (1969), but he did not choose to describe them at the time. Very Many species of Gomphandra have a poor collection record, few additional specimens have been collected since, and it is and a few are known only from the type collection. Ideally, a unlikely that more material will be collected in the future, as all new species publication would include descriptions of pistillate three species described below are probably either extinct or flowers, staminate flowers, and mature fruit. However, for the critically endangered by habitat loss. poorly known species of Gomphandra, complete reproductive material is usually lacking. Nonetheless, new species can be described if their morphologies are distinctive enough to 1. Gomphandra palustris Schori, sp. nov. — Fig. 2; Map 1 preclude confusion with previously described taxa. Two of the Arbor ad 25 m alta. Folia coriacea, ovata-ellipsoidea ad obovata vel fere species described below were recognized as new by Sleumer orbiculata, 5.6–13.0 cm longa, 2.6–6.7 cm lata, nervis secundariis 4–5(–6) utrinque, desuper impressis, superioribus ante marginem confluentibus. 1 Department of Environmental & Plant Biology, Ohio University, Athens, OH Inflorescentiae ignotae. Infructescentiae cymosae, ramis primariis usque 45701, USA; corresponding author e-mail: [email protected]. quatuor, axillares aut terminales. Fructus 1.9–2.1 cm longi, 0.9 cm lati, 2 Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AB, UK. ellipsoidei sed latissimi in partem superiorem; putamen protrusum ultra © 2010 Nationaal Herbarium Nederland You are free to share - to copy, distribute and transmit the work, under the following conditions: Attribution: You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work). Non-commercial: You may not use this work for commercial purposes. No derivative works: You may not alter, transform, or build upon this work. For any reuse or distribution, you must make clear to others the license terms of this work, which can be found at http://creativecommons.org/licenses/by-nc-nd/3.0/legalcode. Any of the above conditions can be waived if you get permission from the copyright holder. Nothing in this license impairs or restricts the author’s moral rights. 190 Blumea – Volume 55 / 2, 2010 excentricum stigma, valde porcatum. — Typus: Haji Bujang S.30259 (holo pubescence. Fruit obovate-ellipsoid, widest in upper half, apex A; iso K, L), Malaysia, Sarawak, 3rd Division, Batang Igan, Sungai Tutus and base rounded, 1.9–2.1 by 0.9 cm, glabrous; subtended by Logging Camp, 6 Sept. 1970. persistent calyx 3 mm diam; inner mesocarp with c. 7 strong Small tree to 25 m high and 40 cm diam; trunk fluted (to 2 m) or longitudinal ridges, stigma distinctly eccentric in dried fruit, 3 mm not. Twigs pubescent with minute, somewhat appressed hairs diam, facing away from sulcus. when young, eventually becoming glabrescent, 1.5–3.0 mm Distribution — Only from Borneo, Sarawak. diam, terminal buds falcate, densely covered with light brown Habitat & Ecology — Only collected from (peat) swamp pubescence. Leaves coriaceous, ovate-elliptic to obovate or forests at low elevations up to 3 m. almost orbicular, frequently conduplicate, apex acute to shortly Field notes — Bark smooth to narrowly longitudinally fissured and abruptly acuminate, base acute, lamina shortly decurrent with a somewhat scabrous surface, grey or pale yellowish grey, onto the petiole, margin flat to slightly revolute, glabrous above inner bark orange. Fruit pinkish white, orangey-pink, or yellow- when mature, sparsely pubescent along the veins below, shin- ish grey. ing above when dried, matte below, 5.6–13.0 by 2.6–6.7 cm; Notes — Gomphandra palustris is distinguished by its midrib sunken above, raised below, secondary veins 4–5(–6) rounded, coriaceous leaves with impressed brochidodromous pairs, impressed above, weakly brochidodromous with the up- veins, and its strongly ridged, asymmetrical fruit. It is not similar per pairs joining 1–2 mm from the margin, concolorous above, to any other species in Borneo and is probably most closely darker than the leaf surface below and raised, tertiary veins related to the Philippine G. luzoniensis (Merr.) Merr. group, generally not visible above, ± raised below, percurrent and whose members have a similar infructescence structure, fruit perpendicular to the midrib; petioles grooved, initially tomen- size and colour. All collections, to date, are fruiting specimens tellous but glabrescent with age, 1.0–2.5 cm by 1.0–1.6 mm. collected from June through October. On specimens with im- Inflorescences and flowers not known. Infructescences with mature fruit, the young ovaries are strongly cylindrical, with no up to 5 fruits developing (out of perhaps 12 or more flowers), evident asymmetry. either terminal on sympodial branches, or axillary, when axillary, most often on the older, naked portion of the twigs, cymose with 2–3 degrees of branching, up to 4 branches borne on a common peduncle to 1.5(–2.0) cm long, branches to 1.2 cm long, fruit sessile or on short pedicels when more than one fruit develops per branch, all axes and calyx with minutely appressed b Fig. 2 Gomphandra palustris Schori. a. Habit of twig with fruit; b. fruit, sulcus not visible (Haji Bujang S.30259). — Scale bars = 1 cm. a M. Schori & T.M.A. Utteridge: Three new species of Gomphandra 191 magnification). Leaves coriaceous, lanceolate-elliptic to ovate, mostly oblanceolate-elliptic, apex acuminate to caudate with an acumen c. 7 mm long, sometimes with a short mucro formed by the tip of the midrib, base acute, margins revolute, apparently glabrous, pale yellowish brown when dried, 5.5–9.0 by 2.0–3.5 cm; midrib slightly impressed above, raised below, secondary veins 4–8 pairs, flat or not evident above, scarcely evident below, brochidodromous, intersecondaries common, tertiary veins not evident on mature leaves; petiole grooved, 9–15 by 1.1–1.5 mm. Inflorescences unknown, probably borne on new flushes of growth. Infructescences with 2–5 fruits in a very reduced cyme, axillary, on previous season’s growth, peduncle 1–2 cm long, pedicels 1.5–5.0 mm long, glabrescent. Fruit glo- bose, slightly asymmetrical, glabrous, 1.0–1.3 by 0.8–0.9 cm; subtended by the persistent cupular calyx 2.0–2.5 mm diam; inner mesocarp with c. 12 faint ribs, stigma discoid, c. 2 mm diam, eccentric. Distribution — Endemic to the Philippines, restricted to Mt Halcon on Mindoro. Habitat & Ecology — On a ridge at 1 200 m, in a forest domi- nated by gymnosperms and Tristania, on gravel/sand, possibly from a quartz base, and from cloud forest at 1 350 m.