Entry From
Flora of Tropical East Africa, page 1, Author: MARTIN CHEEK AND LAURENCE DORR
Names
Octolobus spectabilis Welw. [family STERCULIACEAE], in Trans. Linn. Soc. 27: 18 (1869); Germain in F.C.B. 10: 260 (1963); Cheek & Frimodt-Moeller in K.B. 53: 682 (1998). Type: Angola, Pungo Andongo, Barranca da Pedro Songue, Welwitsch 1202 (BM, holo.)
Octolobus angustatus Hutch. [family STERCULIACEAE], in K.B. 1937: 395 (1937). Type: Ghana, Kwahu Prasu, Vigne 1602 (K!, holo.)
Information
Tree 7(–15) m tall, ± 30(–60?) cm diameter at breast height; bole cylindrical, lacking buttresses, bark brownish with longitudinal fissures; stems of flowering branches terete or slightly ridged, 2–3.5 mm diameter, white to brown, black scurfy with stellate hairs, glabrescent, internodes 0.5–3(–5) cm long. Leaves elliptic, obovate or oblanceolate, 7–20(–30) cm long, 2.8–7.5(–13) cm wide, apex short to long-acuminate, acumen 10–15(–28) mm long, 4–5 mm wide, base attenuate and abruptly rounded-truncate or obtuse, lateral nerves 4–9 on each side of the midrib; petiole 0.5–5(–12) cm long; stipules 5–7 mm long, 1 mm wide. Inflorescence with bracts papery, broadly ovate to oblong, 1.5–8 mm long, 1–5 mm wide, apex truncate to mucronate, glabrous or densely velutinous. Flowers creamy-yellow, perianth outer surface densely golden-brown stellate-pubescent, with proximal tube short- or long-cylindrical, 4–11 mm long, 5–8(–20) mm wide, inner surface with thinly scattered patent, simple hairs; lobes 12–14(–22) mm long, 3–5(–10) mm wide, inner surface densely papillose, with a membranous margin ± 2 mm wide, glabrous. Female flowers with androgynophore 0.5–1 mm long, glabrous, carpels 8–30 in a globose mass ± 1 cm long, carpels oblong, 4 mm long, 1.5 mm wide, densely white tomentose, stigmatic heads glossy, black. Male flowers with androgynophore 3–5 mm long, 0.7 mm wide, glabrous, staminal head shortly cylindrical, 3 mm long, 4 mm wide. Fruit red, densely but shortly tomentellous, with accrescent pedicel and androgynophore combined 1.5 cm long, stout; carpels obovoid or shortly ellipsoid-cylindrical, 1.4–3.5 cm long, 1.1–2.8 cm wide, with a wide raised ventral ridge, stipe (0.2–)0.8–1.5 cm long, 0.2–0.3 mm wide, rostrum 0.4–0.8 cm long, 0.2–0.3 cm wide. Seed glossy black, ellipsoid, often faceted, 1–2.1 cm long, 0.8–1.2 cm wide, hilum ± 1 cm diameter. Fig. 6, p. 47.
Distribution
TANZANIA Iringa District Udzungwa Scarp Forest Reserve, 35° 58’ E, 8° 21’ S, Dec. 1997, Frimodt-Moeller, Ndangalasi & Joeker TZ 540!
Notes
CONSERVATION This species though never very common, is widespread in Africa and is known from more than 15 sites. While there are some threats to its habitat at the single E African site, threats at other sites have not been evaluated. It is rated here as “Near Threatened”. This genus is so far represented in E Africa by a single specimen, overgrowing a stream in a steep, inaccessible gorge where several other new or rare species have been found, for example Afrothismia sp., Ancistrocladus tanzaniensis Cheek & Frimodt-Moeller, Trichilia lovettii Cheek and Cola stelechantha Brenan. This collection represents an extreme variant of the polymorphic Octolobus spectabilis, having much larger leaves (to over 30 ≈ 11 cm) than any specimen known from W Africa where leaves are usually no more than ± 20 ≈ 8 cm. Furthermore, the leaves of the Tanzanian collection are elliptic, with a rounded to obtuse base, rather than being obovate, or narrowly elliptic with an acute or cuneate base. However, since this species is already known to be exceedingly variable in perianth shape and indumentum, and in stipule shape, size and persistence, it would be unsatisfactory to recognize this particular variant without recognizing the others that occur. This species was recently reported by Mbago (pers. comm. to Luke 2006) from West Kilombero scarp, Forest Reserve Nyumbanitu-Udekwa, fr. Dec. 1999, 1000m alt. (Mhoro and Frontier in Mbago 1822) but I have not seen the specimen. The species is also listed in the Mtwara report of Frontier Tanzania, but there is no specimen to substantiate this claim, so the record must be treated as dubious.