Isolona zenkeri Engl., Notizbl. Bot. Gart. Berlin-Dahlem 2: 301 1899
Creators: name: Couvreur, Thomas L. P.
name: Dagallier, Leo-Paul M. J.
name: Crozier, Francoise
name: Ghogue, Jean-Paul
name: Hoekstra, Paul H.
name: Kamdem, Narcisse G.
name: Johnson, David M.
name: Murray, Nancy A.
name: Sonke, Bonaventure
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Magnoliales
Annonaceae
Isolona
Isolona zenkeri

description: Isolona zenkeri Engl., Notizbl. Bot. Gart. Berlin-Dahlem 2: 301, 1899 Figs 40, 41; Map 5H Type. Cameroon. South Region; Bipindi, <i>Zenker G.A. 1186</i>, 1896: holotype: B[B 10 0154218]; isotypes: BM <i>n.v.</i>, G[G00011574]; K[K000199013]; WU[WU0025863]. Description. Tree to shrub, 7-15 m tall, d.b.h. up to 15 cm; stilt roots or buttresses absent, trunk not fluted. Indumentum of simple hairs; old leafless branches glabrous, young foliate branches glabrous. Leaves: petiole 2-6 mm long, ca. 2 mm in diameter, glabrous, <b>slightly grooved, blade inserted on top of the petiole</b>; blade 16-23 cm long, 6.5-8.5 cm wide, oblong to oblanceolate, apex abruptly acuminate, acumen 1-2 cm long, base rounded to acute, coriaceous, below glabrous when young and old, above glabrous when young and old, concolorous; midrib raised above, above glabrous when young and old, below glabrous when young and old; secondary veins 11 to 13 pairs, glabrous below; tertiary venation reticulate. Individuals bisexual; inflorescences ramiflorous on young foliate branches, axillary. Flowers with 9 perianth parts in 2 whorls, 1 to 2 per inflorescence; pedicel 3-7 mm long, ca. 1 mm in diameter, glabrous; in fruit 5-15 mm long, 2-3 mm in diameter, glabrous; bracts 2 to 4, all basal, 1 mm long, 1 mm wide; sepals 3, valvate, free, 2-5 mm long, 2-4 mm wide, ovate, apex acute, base truncate, green to brown-red, glabrous outside, glabrous inside, margins flat; petals basally fused, tube 4-7 mm long, inner and outer whorl not differentiated, equal; <b>lobes 15-25 mm long, 3-4 mm wide, lorate (strap-shaped) to oblong, apex acute, light yellow to light green, margins curved inwards</b>, glabrous outside, glabrous inside, erect over receptacle, <b>verrucose when dried</b>; stamens ca. 40, in 3 to 4 rows, ca. 2 mm long, broad; connective discoid, glabrous, cream; staminodes absent; carpels fused into a single structure, ca. 3 mm long, stigma bilobed, slightly capitate, glabrous. Fruit syncarpous, sessile, 30-65 mm long, 15-30 mm in diameter, ellipsoid to globose, <b>apex rounded, glabrous, smooth, faintly ribbed to longitudinally ribbed</b>, green turning yellow when ripe; seeds not counted, 15-20 mm long, 8-10 mm in diameter, ellipsoid; aril absent. Distribution. Known from Cameroon to the west of Republic of Congo; in Cameroon known from the South and Littoral regions. Habitat. A fairly infrequent species, growing in lowland rain forests. Altitude 0-800 m a.s.l. Local and common names known in Cameroon. None recorded. IUCN conservation status. Least Concern (LC) (Cosiaux et al. 2019x). Uses in Cameroon. None reported. Notes. <i>Isolona zenkeri</i> is characterized by its coriaceous corolla lobes with incurved margins, erect above the receptacle, and verrucose when dried. Specimens examined. <b>South Region</b>: Bipinde, 3.26°N, 10.20°E, <i>16 June 1918</i>, <i>Annet E.</i> 359 (WAG); 12 km from Kribi N of Ebolowa road between Kribi aifield and Kienke R, 2.88°N, 9.983°E, <i>18 June 1969</i>, <i>Bos J.J.</i> 4866 (BR,K,LM,MO,P,POZG,WAG,YA); 6 km N of km Kribi-Lolodorf, 3.08°N, 10.25°E, <i>12 March 1970</i>, <i>Bos J.J.</i> 6522 (BR,K,P,WAG,YA); Campo-Ma’an area Bibabimvoto, 2.25°N, 10.36°E, <i>01 February 2000</i>, <i>Elad M.</i> 1269 (WAG); Campo-Ma’an area Ebianemeyong, 2.46°N, 10.29°E, <i>24 May 2002</i>, <i>Elad M.</i> 1545 (KRIBI,WAG); 3 km S of Kwambo and 6 km WSW of Bipindi, 3.05°N, 10.36°E, <i>19 January 1987</i>, <i>Manning D.</i> 1453 (MO); Campo-Ma’an area Bifa, 2.65°N, 10.28°E, <i>12 October 2001</i>, <i>Tchouto Mbatchou G.P.</i> BIFAX_2 (WAG); Campo-Ma’an area Bibabimvoto, 2.21°N, 10.01°E, <i>13 May 2000</i>, <i>Tchouto Mbatchou G.P.</i> 2855 (KRIBI,WAG,YA); Campo-Ma’an area Bibabimvoto, 2.25°N, 10.04°E, <i>24 August 2000</i>, <i>Tchouto Mbatchou G.P.</i> 3009 (KRIBI,WAG,YA); Bipindi, 3.08°N, 10.41°E, <i>1896</i>, <i>Zenker G.A.</i> 1186 (B,BM,G,K); Bipindi, 3.08°N, 10.42°E, <i>01 January 1907</i>, <i>Zenker G.A.</i> 3375 (P); Bipindi, 3.08°N, 10.41°E, <i>01 January 1908</i>, <i>Zenker G.A.</i> 3471 (US); Bipindi, 3.08°N, 10.41°E, <i>01 January 1912</i>, <i>Zenker G.A.</i> 4405 (G,K,MO).
description: Published as part of <i>Couvreur, Thomas L. P., Dagallier, Leo-Paul M. J., Crozier, Francoise, Ghogue, Jean-Paul, Hoekstra, Paul H., Kamdem, Narcisse G., Johnson, David M., Murray, Nancy A. &amp; Sonke, Bonaventure, 2022, Flora of Cameroon - Annonaceae Vol 45, pp. 1-532 in PhytoKeys 207</i> on pages 151-153, DOI: 10.3897/phytokeys.207.61432
description: {"references": ["Cosiaux, A, Couvreur, TLP, Erkens, RHJ, 2019x. Isolona zenkeri. The IUCN Red List of Threatened Species: e.T45418A132677592. https://doi.org/10.2305/IUCN.UK.2019-3.RLTS.T45418A132677592.en"]}