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<taxonx xmlns:dc="http://digir.net/schema/conceptual/darwin/core/2.0" xmlns:mods="http://www.loc.gov/mods/v3" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
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<taxonxHeader>
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<mods:mods>
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<mods:titleInfo>
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<mods:title>Lemurophoenix (Palmae: Arecoideae), a new genus from Madagascar</mods:title>
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</mods:titleInfo>
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<mods:name>
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<mods:namePart type="family">Dransfield</mods:namePart>
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<mods:namePart type="given">J.</mods:namePart>
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</mods:name>
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<mods:originInfo>
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<mods:publisher>Kew Bulletin, Vol. 46, No. 1, pp. 61-68</mods:publisher>
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<mods:dateIssued>1991</mods:dateIssued>
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</mods:originInfo>
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</mods:mods>
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</taxonxHeader>
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<taxonxBody>
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<treatment rank="species">
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<nomenclature>
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<name>Lemurophoenix halleuxii</name>
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<author>J. Dransf.</author>
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<citation>Kew Bull. 46: 62 (1991)</citation>
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<type>Madagascar; Dransfield et al.; JD 6453</type>
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<type_loc>Holotypus K; isotypi BH, MO, NY, P, TAN</type_loc>
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</nomenclature>
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<div type="introduction"><p></p></div>
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<div type="etymology"><p>"Hovitra vari mena"</p></div>
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<div type="vernacular"><p></p></div>
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<div type="diagnosis"><p>Palma pergrandis, formosis- sima solitaria caule usque 20 m et columna coronae roseo-griseata usque 1.5 m longa; rachis folii usque 4.25 m longa foliolis c. 60 utrinsecus regulariter dispositis; inflorescentia usque 2 m longa pedunculo usque 50 cm; bracteae (prophyllum et bractea peduncularis) extus carmesinae intus cremeae; rachillae c. 110, usque 40 cm longae, cremeae demum virides; flos masculus alabastro 8 x 4 mm, petalis anthesin reflexis, staminibus receptaculo tumido portatis; fructus c. 50 mm diam.</p></div>
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<div type="description"><p>Immense tree palm. Trunk to 20 m tall, at base c. 1 m diam., higher up c. 50 cm diam., pale brown, leaf scars c. 10 cm apart. Leaf to 4.5 m long; crownshaft c. 1.5 m long, c. 50 cm diam., the leaf-sheath greyish pink when newly exposed, bearing scattered dark brown peltate scales and abundant white wax; petiole to 25 cm long, c. 10 cm wide and 5 cm thick at the base; leaflets very regular, c. 60 on each side of the rachis, stiff, rich dark green, c. 6 cm distant, linear-lanceolate, the proximal c. 65 x 2 cm, in mid leaf c. 95 x 6 cm, decreasing abruptly in size to 17 x 0.7 cm near the tip; rachis when young bright crimson, young blade flushed red. Inflorescence very robust, c. 2 m long; peduncle c. 50 cm long, grossly swollen and winged to c. 35 cm wide at the base, decreasing to 10 x 4.5 cm near the insertion of the first branch, the surface densely covered with rough brown scales; prophyll and peduncular bract abaxially bright crimson, cream-coloured within; prophyll to 90 cm, splitting along one side, inserted c. 15 cm above the base of the peduncle; peduncular bract to 120 cm long, inserted c. 10 cm above the prophyll insertion; first-order branches c. 12-15, the basal devoid of branches in the basal 20-25 cm, to 4-5 cm thick; rachillae c. 110, cream-coloured at anthesis, becoming green, to 40 cm long, c. 8-9 mm diam., somewhat swollen, with flowers partially embedded in shallow pits c. 6-10 mm apart, rachilla surface minutely papillose and scaly; rachilla bracts c. 2 x 8 mm, fleshy. Staminate flower-bud pale greenish brown, c. 8 x 5 mm, at anthesis the flower with a spread of c. 14 mm; sepals connate in the basal 0-8 mm, c. 3.5 x 6 mm, c. 2 mm thick at the keel, the margin minutely ciliate, otherwise glabrous; petals c. 7 X 3 mm, pale brown, later the floral receptacle carrying the petal bases c. 4 mm above the calyx, the petals becoming reflexed by a pulvinus to 1.5 mm thick at the petal bases; stamens 52-59, borne on the receptacle c. 4-5 mm wide, filaments 2-4 x 0.1 mm, anthers c. 2 x 0.5 mm; pistillode, c. 1.5 x 0.2 mm, hidden among the filament bases. Pistillate flower in immature bud, c. 4-5 mm diam.; sepals c. 3.5 x 4.5 mm diam.; petals c. 3.5 mm long; staminodes 10-12, 0.4 x 0-2 mm; gynoecium c. 2.5 X 1.5 mm. Fruit chestnut brown, globose, at maturity c. 50 mm diam., the epicarp cracked into corky warts less than 1 mm high and 2.5 mm across; mesocarp c. 8 mm thick, whitish; endocarp spherical, c. 33 mm diam., 1 mm thick, deep brown, with a basal heart-shaped pale brown button c. 11 x 11 x 7 mm. Eophyll flushed reddish-brown when newly emerged.</p></div>
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<div type="distribution"><p></p></div>
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<div type="biology_ecology"><p>Lemurophoenix halleuxii occurs in a steep-sided valley below the long ridge-top leading eastwards from the village of Sahavary. The valley is at about 350-450m above sea level. There is a great abundance of different palms in the forest here, yet there is little peculiar about the habitat. Furthermore, Lemurophoenix does not occur in similar valleys nearby. As one drops down from the crest of the ridge, suddenly one becomes aware of immense palms in the forest canopy in the valley bottom, the huge greyish-pink crownshafts and vast bunches of fruit standing out amidst the surrounding green. There are about 30 mature individuals and about 20 juveniles in various stages of development. Beneath the mature trees lie thick carpets of bare endocarps, either newly fallen or rotting. Seedlings are distinctive but very scarce. It appears that there is little effective dispersal and very limited regeneration and it is difficult to imagine which extant Malagasy animal might be capable of dispersing the rather large diaspore. It is not known to occur anywhere else in the vicinity of Maroantsetra or on the Masoala Peninsula.
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The horticultural potential of this palm could be very great indeed. It has the stature of the Caribbean royal palm, Roystonea oleracea, but has the added attraction of the wonderfully pink-tinged grey crownshaft. As a specimen tree for tropical gardens or for avenues it would be spectacular indeed, if it is amenable to cultivation. Unlike the easily cultivated Malagasy palms Chrysalidocarpus lutescens, C. madagascariensis, Bismarckia nobilis and Neodypsis decaryi, Lemurophoenix occurs in one of the warmest and wettest parts of the island so it may be less tolerant than these others, now so widespread in cultivation. Lemurophoenix halleuxii, as "Red-Lemur Palm", is now well known to the more avid palm collectors throughout the world and every year large quantities of ripe seed from the only known population are harvested and exported. The removal of seed, if it continues at this rate, will ultimately affect the regeneration of the palm and endanger its survival.</p></div>
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<div type="conservation"><p></p></div>
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<div type="uses"><p></p></div>
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<div type="discussion"><p>The most difficult problem still requiring solution is the affinities of this majestic palm. The pinnate leaf and the arrangement of flowers in triads of a central pistillate and two lateral staminate clearly indicate that it belongs to subfamily Arecoideae (Uhl and Dransfield 1987). The reduplicate vernation, the presence of only two large bracts in the inflorescence (the prophyll and a peduncular bract) and the pseudomonomerous gynoecium (i.e., a gynoe- cium with a single fertile locule but with vestiges of two further locules) further narrow the affinity to tribe Areceae, but to which subtribe of this, the most variable of tribes in Arecoideae, the palm is most closely related is not obvious. The corky-warted fruit is present in Manicariinae and two genera of Iguanurinae (Sommieria and Pelagodoxa), but the former has trilocular, triovulate gynoecia while the fruits of genera in the latter subtribe (which consists of genera with pseudomonomerous gynoecia) have a conspicious operculum in the endocarp that is lacking in the "red-lemur palm" Besides, such corky-warted fruits are found in several quite unrelated palm genera (see Uhl and Dransfield 1987) suggesting that this epicarp condition may have arisen several times in the evolutionary history of the family, Multistaminate flowers occur in many arecoid subtribes and the ontogeny of multistaminy is various (Uhl and Moore 1980), again suggesting that the presence of more than six stamens may have arisen several times. One of the most curious features is the internal fruit structure. The endocarp bears a basal heart-shaped button which seems to represent the sclerified vascular supply next to the chalaza. Such a structure is also present in Orania and Halmoorea in the Oraniinae (and in members of subfamily Phytelephantoideae); however, members of Oraniinae are tricarpellate and triovulate and are vegetatively and in inflorescence structure both rather uniform and quite different from the red-lemur palm. Apart from the presence of more than six stamens, the staminate flowers do bear a resemblance to those of larger members of the quintessentially Madagascar subtribe Dypsidinae, but, without drastically altering the circumscription of the Dypsidinae, an otherwise apparently very natural group, the "red-lemur palm" cannot be included. It may be necessary to create a new monotypic subtribe for this very distinctive new genus, but even so this does not solve the problem of which subtribe of Areceae is the sister group. A greater understanding of the relationships will require developmental study and may be helped by cladistic studies in progress (Dransfield and Uhl, in prep.) and until then I defer the subtribal placement.</p></div>
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<div type="materials_examined"><p>MADAGASCAR. Maroantsetra, Andranofotsy River, Sahavary, hills east of village, Andilampananina, primary forest, deep narrow valley at 350-450 m, 23 Oct. 1986, Dransfield, D. N. Cooke, A. Rakotozafy,J. H. Beach, P. P. Lowry and G. Jean JD 6402 (BH, K, MO, NY, P, TAN); 10 Feb. 1988, DransJield, A. J. Henderson and M. Staniforth JD 6453 (holotype K; isotypes BH, MO, NY, P, TAN). </p></div>
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</treatment>
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</taxonxBody>
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</taxonx>
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