Tuesday, August 12, 2025

[Botany • 2025] Ozoroa bhangazica (Anacardiaceae: Anacardioideae) • A New Species from Maputaland, South Africa


Ozoroa bhangazica R.G.C.Boon & A.E.van Wyk, 

in Boon et van Wyk, 2025. 
Artwork by Daleen Roodt.

Abstract
Ozoroa bhangazica, a clonal, fire-adapted geoxylic suffrutex, is formally described as a new species with a highly restricted distribution in the Maputaland Centre of Endemism in KwaZulu-Natal Province, South Africa. It is confined to Maputaland Wooded Grassland on Quaternary coastal sands, a vegetation type notable for its rich diversity of geoxylic suffrutices. The two known populations are included in the iSimangaliso Wetland Park, a World Heritage Site. In southern Africa, Ozoroa species are divided into two groups based on leaf and pollen characters; O. bhangazica belongs to Group A and is unique among KwaZulu-Natal species for its geoxylic growth form. The genus shows significant infraspecific vegetative variation, with O. bhangazica displaying distinct variation in leaf size and shape between new shoots after fire and regrowth that has persisted through one or more fire-free seasons. Morphologically, the new species resembles O. barbertonensis, another geoxylic suffrutex, which is a geographically isolated serpentine endemic confined to the Barberton Centre of Endemism about 250 km from where O. bhangazica occurs. Both share the characteristic of linear to narrowly oblong leaves following fire. However, O. bhangazica can be distinguished by its longer, broader leaves, which are mostly glabrous on the upper surface with flat (non-revolute) margins, a longer petiole, and larger mature drupes. A provisional conservation status of Near Threatened (NT) is recommended under IUCN Red List criteria.

classification, endemism, geofrutex, geoxyle, geoxylic suffrutex, grassland, iSimangaliso Wetland Park, KwaZulu-Natal, Maputaland Centre of Endemism, Maputaland-Pondoland-Albany Hotspot, pollen, taxonomy, underground trees, Eudicots

Ozoroa bhangazica: leaf, flower and fruit morphology.
A. Plant (ca. 600 mm high) in flower. B. Leaves from a recently sprouted post-fire plant, showing craspedodromous venation; blade with silvery-white abaxial surface, green and mostly hairless adaxial surface, except for hairs along the midrib and main veins. C. Older female flowers with early fruit development. D. Male flowers. E. Mature fruit. Photographs by R.G.C. Boon.

Ozoroa bhangazica: habitat and habit.
A. Maputaland Wooded Grassland on Quaternary coastal dunes, showing a mix of grasses and broad-leaved geoxylic suffrutices. B. Clone with multiple ramets emerging shortly after fire; note the silvery-white underside of leaves. C. Post-fire ramets (ca. 250 mm high) with developing inflorescences. D. Mature growth (ca. 1 m high) unburned for one or more seasons, bearing mature fruit and relatively broad leaves. Photographs by R.G.C. Boon (A, C & D) and W.S. Matthews (B).

Ozoroa bhangazica.
 A. Two flowering shoots (ramets) sprouting from a partially exposed lignotuber after fire. B. Relatively broad leaf from regrowth that has persisted through one or more fire-free seasons. C. Male flowers. D. Female flowers. E. Mature fruit. F. Stem section from regrowth that has persisted through one or more fire-free seasons showing bark with lenticels. Artist: Daleen Roodt.

Ozoroa bhangazica R.G.C.Boon & A.E.van Wyk, sp. nov. 

 Diagnosis:—A member of Ozoroa Group A; distinguished from all other species of Ozoroa in KZN Province, South Africa, by being a clonal geoxylic suffrutex not exceeding 1.5 m in height (vs. non-clonal shrubs or trees >2 m tall). Morphologically resembling O. barbertonensis in also being a geoxylic suffrutex with linear to narrowly oblong leaves on new growth following a fire, but differing as follows: lamina of post-fire leaves 80–110(–130) mm long [vs. shorter, (23–)55–80(–90) mm], (6–)9–18 mm wide [vs. narrower, (2–)4–7(–8.5) mm], adaxially glabrous except for midrib and secondary veins (vs. ca. uniformly hairy), with margin plane (vs. revolute); petiole 5–18 mm long (vs. shorter, 1.5–3.0 mm); mature drupe when dry 10 × 7 mm (vs. smaller, 4.5–5.0 × 6.0–6.5 mm); confined to Maputaland Centre of Endemism where it grows on nutrient-poor Quaternary coastal sands (vs. a serpentine endemic confined to Barberton Centre of Endemism)

Etymology:—The specific epithet “bhangazica” refers to the fact that the species is currently known only from the vicinity of Lake Bhangazi North and Lake Bhangazi South in the iSimangaliso Wetland Park World Heritage Site in KZN Province, South Africa. 
The name of the lakes derives from the Zulu word umbhangazi, which refers to various quick-growing trees— Zulu names of geographical features are often named for the dominant vegetation there (A. Koopman, perscomm.).


Richard G.C. BOON and Abraham E. VAN WYK. 2025. A New Species of Ozoroa (Anacardiaceae: Anacardioideae) from Maputaland, South Africa.  Phytotaxa. 714(2); 103-117. DOI: doi.org/10.11646/phytotaxa.714.2.1 [2025-08-08]