Encephalartos Ituriensis (Zamiaceae): an Emended Description
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Encephalartos ituriensis (Zamiaceae): an emended description Piet VORSTER Department of Botany, University of Stellenbosch, Private Bag X1, 7602 Matieland, South Africa. [email protected] Roy E. GEREAU Missouri Botanical Garden, P.O. Box 299, St. Louis, MO 63166-0299, U.S.A. [email protected] ABSTRACT The original description of Encephalartos ituriensis (Zamiaceae) is incomplete, to some extent inaccurate and based in patt on immature material. Based on KEYWORDS subsequently collected material and on observations in situ, an emended des Encephalartos ituriensis, Zamiaceae, cription with illustrations of the fronds and mature female cones is pro D.R. Congo vided. RESUME La description originale à'Encephalartos ituriensis (Zamiaceae) est incomplète, parfois inexacte, et en partie fondée sur un matériel immature. Grâce à des MOTS CLÉS échantillons récoltés postérieurement et aux observations de tertain, une des Encephalartos ituriensis, Zamiaceae, cription amendée, avec des dessins de frondes et de cônes femelles mûts, est R.D. Congo présentée. The original description of Encephalartos itu sculpturing of the exposed faces of the sporo- riensis Bamps & Lisowski (BAMPS & LlSOWSKl phylls is ambiguous. No information was given 1990) was fairly detailed, but many of the data concerning the color of male and female cones, presented there were ambiguous or incomplete, the presence or absence of a petiole, the indu to the extent that when the second author saw mentum of the cones, the texture of the leaflets, plants in nature, he thought that they could and the distribution of teeth on the leaflets, all tepresent a different species. The size of the chatacters consideted diagnostic by VORSTER female cone given in the ptotologue is incorrect (1990 and in ptess). No illustrations of any part and the information given concerning the surface of the mature frond were given; only a line draw- ADANSONIA, sér. 3 • 1998 • 20(1) 211 Vorster P. & Gereau R.E. ing was provided of a seedling plant with two floccose tawny indumentum on cataphylls. leaves. GOODE (1989: 229-231) published Fronds numerous, spreading-ascending in a detailed color plates of a whole plant, leaflets, hemispheric crown, straight, dark glossy green, cones, and sporophylls, purportedly of E. itu- 2-3 m long, sessile; base of rachis covered with riensis, in the year before the valid publication of short tawny floccose indumentum; leaflets ca. 80 the binomial. However, the provenance of the pairs, gradually reduced to a series of prickles material illustrated cannot be established. toward base of frond; median leaflets in plane GoODE's habit illustration was based on a photo view oriented at angle of ca. 60° with rachis and graph of a cultivated plant growing on the shore pointing toward frond apex, opposing leaflets set of Lake Kivu and said to be from the Ituri Forest. at angle of slightly less than 180° to each other The cones that he illustrated are from a different on circumference of rachis, narrowly oblong- plant and were received from a collector in lanceolate and tapering to acute but not pungent Zimbabwe without any locality data. GOODE apices, not or slightly falcate, with (3-)4-6(-9) (1989: 230) provided no scale of magnification teeth rather evenly distributed along both mar for the illustrations of the leaflets, and the gins and ca. 3 teeth crowded near base of distal dimensions of 20 X 12 cm given for the female matgin, in dried specimens finely corrugated on cone (GOODE 1989: 231) are obviously incorrect abaxial surface and margins (including margins considering the relative size of the stem apex and of teeth), revolute, not or only slightly overlap frond bases attached. ping, somewhat soft-textured, 19-30 X 2-3 cm (excluding teeth). Male cone [not seen, descript The type material as well the additional speci ion from BAMPS & LISOWSKI (1990)] number mens cited by BAMPS & LISOWSKI (1990) all unknown, narrowly ellipsoid, borne on a stout come from near Nduye in the northeastern peduncle to 16 cm long and 1.8 cm thick, color Democratic Republic of Congo. After considera not recorded but presumed similar to female tion of the original description, allowance for cone (see below), glabrous, [in dried state?] ca. missing and possibly inaccurate information, and 26 X 7 cm; exposed faces of male sporophylls study of Lisowski 41057 (BR) and herbarium moderately projecting, slightly drooping at specimens and photographs of Gereau et al. 5413 maturity, ca. 2.5 mm wide, the terminal facet (Democratic Republic of Congo, near Nzaro, ca. differentiated, rhombic, its diameter ca. 60% of 30 km northwest of Nduye; EA, epu [reference total horizontal diameter of exposed face; female collection at Epulu], MO, PRE), we conclude cones 1-4, ovoid-cylindrical at maturity, borne that all of these specimens are conspecific. on a peduncle ca. 10 cm long, initially glaucous- Therefore, it is clear that the markedly small green becoming yellow-green at maturity, glab female cones reported for E. ituriensis by BAMPS rous, ca. 55 X 20 cm; exposed faces of female & LISOWSKI (1990) were either depauperate or sporophylls raised, somewhat pyramidal, ca. 7 X not fully developed and that the circumscription 4.5 cm, the terminal facet off-center toward base of the species in the protologue is inadequate. of cone, its diameter 25-33% of total horizontal Accordingly we supply the following emended diameter of exposed face, the median facet diffe description: rentiated, with ridges separating facets clearly dif ferentiated; facets smooth on faces when fresh, tuberculate when dry, margin of exposed face of Encephalartos ituriensis Bamps & Lisowski fresh sporophyll tuberculate. Seed with sarcotesta emend. Vorster & Gereau red when fresh, brown when dry, 37-39 X 21- 28 mm with dried sarcotesta intact, 36-38 X 20- Plant arborescent, palm-like in shape, un- 25 mm with sarcotesta removed.—Fig. 1, 2. branched but sometimes suckering from base; stem to 6 m long and 40-50 cm thick, usually procumbent with apical portion erect when more GEOGRAPHICAL DISTRIBUTION AND HABITAT than 2 m long, covered with leaf base remains in Encephalartos ituriensis is known with certainty a regular pattern, the apex glabrous except for only from the Ituri Forest in the Democratic 212 ADANSONIA, ser. 3 • 1998 • 20(1) Encephalartos ituriensis (Zamiaceae) Fig. 1.—Encephalartos Ituriensis. A, mature female cones in situ; В, mature female cone; С, plant in habitat.—All from Gereau et al. 5413. ADANSONIA. Ser. 3 • 1998 • 20(1) 213 Vorscer P. & Gereau R.E. Fig. 2.—Encephalartos ituriensis: A, basal part of rachis showing leaflets reduced to a series of prickles; B, median leaflets in (1) adaxial and (2) abaxial view; C, exposed face of fresh female sporophyll, showing well-defined and smooth facets; D, exposed face of dried female sporophyll, presenting a tuberculate aspect; E, seed with sarcotesta intact; F, seed with sarcotesta removed (scale bar = 10 cm).—All from Gereau et al. 5413. 214 ADANSONIA, ser. 3 • 1998 • 20(1) Encephalartos ituriensis (Zamiaceae) Republic of Congo at altitudes of 1100-1200 m, of teeth near the base of the distal margin of each from five localities forming an arc over a distance leaflet, and more numerous male cones, up to 8 of some 160 km from near Nzaro south-east borne together wards to near Nyankunde, with coordinates 1- The only other near-equatorial African species 2°N-28-30°E. Fot considerations of conservation with soft-textured leaflets is Encephalartos lauren- we do not publicize the localities in greater tianus De Wild., from the Kwango River valley detail. While most of the surrounding area sup bordering the Democratic Republic of Congo ports a mosaic of mixed moist and single-domi and Angola. This is a larger species, which can be nant moist semi-evergreen Guineo-Congolian distinguished by its larger leaflets (up to 50 X rain forest (WHITE 1983), the habitat of 5 cm), long-peduncled female cones, and a red Encephalartos ituriensis lies outside the fotest at dish indumentum on the cones of both sexes (DE somewhat higher elevations on exposed gtanitic WILDEMAN 1903: 10; 1904: 392; Bois 1907; domes that suppott a xerophytic flora with a GENTIL 1904a,b; LEBRUN 1930). number of disjunct and possibly endemic ele ments (LlSOWSKl 1992). At one locality E. itu DISCUSSION riensis gtows among grass in savanna-like Our emended circumscription of Encephalartos vegetation, but this is appatently a degraded ituriensis excludes the illustiations by GOODE secondary formation that has been altered by (1989: 229-231) for the reasons given above. We grazing of domestic livestock. extend the diagnostic charactets used to recognize the species, and include a larger range of morpho PHENOLOGY logical variation than originally described by Male cones are known only from April BAMPS & LlSOWSKl (1990). Much of the additio (Lisowski 42234), and female cones only from nal morphological variation is due to the plants March (Gereau et al. 5413) and April {Lisowski from Nzaro (cf. Gereau et al. 5413), which are lar 42909). The strong seasonality of the annual ger and more luxuriant than those at Nduye (cf. rainfall tegime in the Ituii Fotest (HART et al. Lisowski 41057). The Nzaro plants have longer 1996: 547), and additionally the edaphic dryness median leaflets with more acute apices and much of the extremely well-drained sites within this larger female cones, but the morphological diffe fotmation on which Encephalartos ituriensis rences between the populations appeat insufficient occuts, make it probable that growth and seed to justify sepatate taxonomic status. production are regulated by precipitation pat terns. The months of March and April corre spond to the end of the single dry season and the Acknowledgements beginning of the rains. The second author thanks John and Tetese HART for their enthusiastic support and warm hospitality during his visits to the Ituri Forest, and Charlotte DIAGNOSTIC FEATURES AND AFFINITIES TAYLOR and Gordon McPHERSON for critical reading Geographically Encephalartos ituriensis occurs of the manuscript.