Oncocalamus mannii (H.Wendl.) H.Wendl., Palmiers : 252 (1878)

Primary tabs

http://media.e-taxonomy.eu/palmae/photos/palm_tc_140143_1.jpg

Distribution

Map uses TDWG level 3 distributions (http://www.nhm.ac.uk/hosted_sites/tdwg/geogrphy.html)
Cameroonpresent (World Checklist of Arecaceae)B
Chadpresent (World Checklist of Arecaceae)B
Congopresent (World Checklist of Arecaceae)B
Equatorial Guineapresent (World Checklist of Arecaceae)B
Gabonpresent (World Checklist of Arecaceae)B
Nigeriapresent (World Checklist of Arecaceae)B
Zairepresent (World Checklist of Arecaceae)B
O. mannii is restricted from southern Cameroon to Gabon. (T.C.H Sunderland, A taxonomic revision of the rattans of Africa (Arecaceae: Calamoideae) in Phytotaxa 51. 2012)A

Biology And Ecology

  • O. mannii is common in open areas, roadside and forest gaps. This species responds extremely well to selective logging and is a common component of regrowth vegetation. (T.C.H Sunderland, A taxonomic revision of the rattans of Africa (Arecaceae: Calamoideae) in Phytotaxa 51. 2012)A

Conservation

  • Least concern (LC) (T.C.H Sunderland, A taxonomic revision of the rattans of Africa (Arecaceae: Calamoideae) in Phytotaxa 51. 2012)A

Etymology

  • Named after Gustav Mann (1836-1916), German botanist and horticulturist. (T.C.H Sunderland, A taxonomic revision of the rattans of Africa (Arecaceae: Calamoideae) in Phytotaxa 51. 2012)A

Description

  • Clustered slender to moderate palm climbing to 15-30 m. Stems without sheaths 8-16 mm in diameter, with 12-28 mm; internodes 12-18 cm long. Leaf sheath longitudinally striate, dark green, tan, often dull crimson brown on young sheaths, moderately to sparsely armed with brown-black spines, concentrated and persistent on the ocrea, spines often sloughing off elsewhere on sheath to leave conspicuous, raised, circular, blister-like scars; thin, white caducous indumentum present on mature sheaths, particularly dense on young sheaths and juvenile individuals; ocrea ± truncate or saddle-shaped with a 0.5-1.8 cm high rounded lobe opposite the rachis, armed as the leaf sheath, spines concentrated at ocrea margin, extending ± 2 cm. Spear leaf deep orange to bright crimson. Juvenile stems up to 6 m long, with sheaths, <1 cm in diameter, leaves sessile or with a short (1.5 cm) petiole, strongly bifid, eventually becoming pinnate, up to 30 cm long and 4.5-6 cm broad at the widest point and with a 60 cm long cirrus emerging from the centre; elaminate rachis often present at base of stem, up to 2.5m long. Leaves on mature stems sessile, or with a short (<2.5 cm) flattened petiole; rachis 1-1.2 m long, abaxially rounded, adaxially concave, becoming circular in cross section distally, armed as the leaf sheath, spines particularly profusely armed on underside, although often smaller than those on the sheath; cirrus 1-1.5 m long, unarmed; leaflets, 25-35 on each side of the rachis, linear-lanceolate, to mildly sigmoid, broadly attenuate at the base, apex somewhat acuminate, 16-32 cm long, 1.8-2.5 cm broad at the widest point, ± concolorous, dark green, armed along the margins with robust spines particularly at base of leaflet, single-nerved, with 6-7 conspicuous secondary nerves on each side; lowermost leaflets smaller than the rest, held vertical to rachis; acanthophylls up to 1.5 cm long. Inflorescences in successive axils 3-5m from stem apex; peduncle 8-15 cm long, hemispherical in cross section; prophyll 3-8 cm long; peduncular bracts 2-4, 2.5-4 cm long; rachis up to 0.8-1m long, pendulous; rachis bracts 2.5-4 cm long; rachillae circular in cross section, 15-28 cm long, pendulous, bracts deep-bright crimson prior to anthesis, becoming dry, brown; prophyll subtending flower cluster 3-5 mm, conspicuously striate. Flower cluster with 1-3 central pistallate flowers subtended by 2 lateral cincinni of 1-2 pistillate and 2-3 staminate flowers; staminate flowers 5.5-6.5 mm × 2-3 mm; calyx ca.5.0 mm × 5.0-5.5 mm, including 1 mm-long stalk, tubular for ½ to ¾ of its length; corolla ca.5 mm long, tubular for the basal ±1 mm, cream/yellow; staminodial tube ca.2 mm long; anthers 0.8 mm × 0.3 mm; pistillode 1.5 mm × 0.7 mm, thin, tapering; pistillate flowers similar to the staminate flowers, up to 3-4 mm wide; ovary ca.2.5 mm × ca.1.5 mm. tipped by 1-1.5 mm long style. Fruitat maturity, globose to sub-globose, 1.8-2.2 cm × 1.6-2 cm, with 15-17 rows of vertical scales. Seed sub-globose 1.2-1.6 cm × 1.5-1.9 cm, with a narrow rounded depression below, covered with regular polygonal depressions, giving a distinctly warty appearance; sarcotesta white, thin (<0.5 mm). (T.C.H Sunderland, A taxonomic revision of the rattans of Africa (Arecaceae: Calamoideae) in Phytotaxa 51. 2012)A

Materials Examined

  • CAMEROON: Asonganyi 279, Bissombo, 59km SE Akono-linga (03º17N:12º28E) sterile, June 12, 1981 (YA!); Bililong & Bullock 351, Campo Reserve, Sud Province (02º14N:09º54E) juvenile, s.d. (K!); Dinklage 1154, Grand Batanga, (02º23N:09º50E) juvenile, February 18, 1891 (HBG!); Letouzey 11776, NE of Mintom II (02º30N:13º30E) juvenile, January 3, 1973 (YA!); Letouzey15317, 40km S of Kribi (02º28N:09º53E) sterile, December 7, 1979 (YA!); Sunderland 1765, 15km from Kribi on Campo road (02º34N:09º50E) sterile, December 1, 1996 (K!, YA!, WAG!); Sunderland 1768, 15km from Kribi on Campo road (02º34N:09º50E) Fr., December 1, 1996 (K!, YA!, WAG!); Sunderland 1769, Kribi?Ebolowa road, 30km west of Kribi (02º39N:10º09E) Fr., December 1, 1996 (K!, YA!, BH!); Sunderland 1790, 15km from Kribi on Campo road (02º34N:09º50E) Fr., March 5, 1997 (K!, YA!, BH!, MO!, BR!); Sunderland 1887, 30km south of Kribi (02º48N:09º43E) Fl. & Fr., November 28, 1997 (K!, YA!, BH!, MO!, WAG!); Sunderland 1888, 30km south of Kribi (02º48N:09º43E) sterile, November 28, 1997 (K!, YA!); Sunderland 1929, Kribi to Campo road: 40km south of Kribi (02º48N:09º53E) Fr., October 12, 1998 (K!, YA!); van Gemerden BJ, Lolodorf (03º05N:10º25E) sterile, s.d. (K!); EQUATORIAL GUINEA: Sunderland1793, Near village of Etembue (01º16N:09º26E) Fl. & Fr., March 13, 1997 (K!, EG!, NY!); Sunderland 1796, 2km north of Ayemeken village (02º10N:10º03E) Fr., March 13, 1997 (K!, EG!, NY!); Sunderland 1900, 10km south of Bata (01º45N:09º43E) sterile, March 20, 1998 (K!, EG!, WAG!); Sunderland 1902, 10km south of Bata (01º45N:09º43E) juvenile, March 20, 1998 (K!, EG!, WAG!); Sunderland 1903, 10km south of Bata (01º45N:09º43E) sterile, March 20, 1998 (K!, EG!); Sunderland 1908, near village of Etembue (01º16N:09º26E) Fl., March 28, 1998 (K!, EG!, WAG!); Sunderland 1916, 20km from Sandje along Cogo road (01º30N:09º40E) Fl., April 7, 1998 (K!, EG!, NY!); Sunderland 1919, 2km WSW of village of Basilé (01º10N:09º50E) juvenile, April 7, 1998 (K!, EG!); Sunderland 1921, On road to Monte Mitra (01º12N:09º59E) Fl., April 7, 1998 (K!, EG!); Sunderland 1923, Near village of Etembue (01º16N:09º26E) Fr., March 28, 1998 (K!, EG!, WAG!); Tessmann 1, sterile, s.d. (FI!); CONGO: Hens 170, Belabo (02º09N:16º04E) sterile, May 8, 1889 (K!); GABON: Klaine s.n., Libreville (00º35N:09º22E) sterile, October 1893 (FI!); Mann 1044, Gaboon River (00º19N:09º29E) Fl., July 1861 (K!); Mann 1044a, Gaboon River (00º19N:09º29E) sterile, s.d. (K!); Rietsma 2151, NNW Libreville (00º36N:09º22E) Fl., April 25, 1986 (LBR!, WAG!) (T.C.H Sunderland, A taxonomic revision of the rattans of Africa (Arecaceae: Calamoideae) in Phytotaxa 51. 2012)A

Bibliography

A. T.C.H Sunderland, A taxonomic revision of the rattans of Africa (Arecaceae: Calamoideae) in Phytotaxa 51. 2012
B. World Checklist of Arecaceae