New Species of Commelina (Commelinaceae) from the Flora of Tropical East Africa Robert B. Faden Department of Botany, National Museum of Natural History, Smithsonian Institution, Washington, D.C. 20560, U.S.A.ABSTRACT. Four new species and one new subspe-cies of Commelina are described from the flora ofTropical East Africa (Kenya, Uganda, and Tanza-nia). Commelina melanorrhiza Faden, C. nairo-biensis Faden, and C. albiflora Faden are endemicto Kenya. Commelina aurantiiflora Faden &Raynsford occurs in Tanzania and Zambia. Com-melina foliacea Chiovenda subsp. amplexicaulisFaden ranges from Uganda and Kenya to Malawiand Zambia. Chromosome numbers are provided forall of these taxa, three for the first time. With more than 120 species, the flora of TropicalEast Africa (Kenya, Uganda, and Tanzania) is therichest in species of Commelinaceae of any countryor regional flora worldwide. In my treatment of theCommelinaceae for Upland Kenya Wild Flowers(Faden, 1974), five species of Commelina could notbe identified and were designated by letters. Sincethen, knowledge of three of them (species "A," "C,"and "E") has increased sufficiently to describe them.A fourth new species, known from Tanzania andZambia and studied in cultivation, is also describedherein. Lastly, the variation in CommelinafoliaceaChiovenda is discussed and found to be circum-scribed best by recognizing two subspecies, one ofthem new. The districts and divisions of the Floraof Tropical East Africa (U1-4, K1-7, T1-8), usedfor the distributions within Uganda, Kenya, andTanzania, follow Polhill (1988).Commelina melanorrhiza Faden, sp. nov. TYPE: Kenya (K1). Samburu Dist.: Ngeng River Val-ley and route to Leiturr, near Ketich Forest Station, Mathews Range Forest, 1014'N, 37�18'E, 5,500 ft. [1,675 m], dry forest with Cordia africana and Croton megalocarpus emergents and Haplocoelum present on rocky outcrop, forest floor and forest road edge, 20 June 1987, A. Faden 87/3 (holotype, US sheet no. 3120251). Commelina sp. "C" of Faden (1974: 657) in Agnew's Upland Kenya Wild Flowers. Figure 1.NOVON 4: 224-235. 1994. Herba perennis radicibus tuberosis et nonnunquam fu-siformibus, atris vel fuscis, surculis annuis, plerumqueprostratis, 6-28 cm longis, foliis distichis laminis petiolatisvel sessilibus, lanceolato-ellipticis ad ovata, 1.5-7 cm lon-gis, (0.8-)1-2.5 cm latis, spathis infundibuliformibus, sub-sessilibus, in extremitatibus ramulorum dense aggregatis,1 1.5 cm longis, 0.8-1.3 cm latis, subglabris ad parcehirsutas, cincinno superiore plerumque bene evoluto, exspatha exserto, unifloro, floribus perfectis et staminatis,petalo inferiore minuto, linearo-lanceolato vel linearo-ob-lanceolato, capsulis trilocularibus, trivalvibus, loculis1-spermis, seminibus subglobosis, 1.6 2 mm diametro,farinosis, crista peripherali incrassato materiae pale brun-neae composita munitis. Shortly rhizomatous perennial with annual shoots.Roots tufted, tuberous, sometimes fusiform, 3-5 mmthick, black or dark brown. Shoots tufted, prostrate(to ascending, in cultivation), 6-28 cm long, notrooting. Internodes to 8 cm long, with a line ofpubescence continuous with the line of fusion of thesheath above, sometimes sparsely puberulous else-where. Leaves distichous, sheath 0.3-1.7 cm long,lacking auricles at the apex, puberulous along theline of fusion and sometimes sparsely so elsewhere,ciliolate or ciliate with white hairs at the apex, laminapetiolate or sessile, lanceolate-elliptic to ovate, 1.5-7 cm long, (0.8-)1-2.5 cm wide, apex acute toacuminate, base strongly oblique, both surfaces sub-glabrous to sparsely puberulous, the abaxial usuallymore pubescent, adaxial surface scabrous, abaxialnot scabrous, margins scabrous. Spathes funnelform, subsessile (peduncles to 5mm long), densely crowded in bracteate clusters atthe ends of the shoots, 1-1.5 cm long, 0.8-1.3 cmhigh, subglabrous to sparingly hirsute, fused for atleast half their width; upper cincinnus often welldeveloped, exserted from the spathe, 1-flowered,with a sparsely puberulous peduncle, this cymesometimes not developed; lower cincinnus 2-5-flow-ered. Flowers perfect (lower cyme) and staminate (up-per cyme), ca. 1.5 cm wide. Pedicels glabrous, thatof the staminate flower 5.5-8 mm long, those ofthe perfect flowers shorter. Sepals green with hyaline
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