''Aloe pearsonii'' (Pearson's Aloe) is a very distinctive and unusual species of

aloe ''Aloe'' (; also written ''Aloë'') is a genus containing over 650 species of flowering plant, flowering succulent plant, succulent plants.WFO (2022): Aloe L. Published on the Internet;http://www.worldfloraonline.org/taxon/wfo-4000001341. Acc ...

, that is naturally

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to the arid

Richtersveld The Richtersveld is a desert landscape characterised by rugged kloofs and high mountains, situated in the north-western corner of South Africa’s Northern Cape province. It is full of changing scenery from flat, sandy, coastal plains, to cragg ...

area on the border between

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

and

Namibia Namibia, officially the Republic of Namibia, is a country on the west coast of Southern Africa. Its borders include the Atlantic Ocean to the west, Angola and Zambia to the north, Botswana to the east and South Africa to the south; in the no ...

Naming and classification

''Aloe pearsonii'' is often considered part of a group of southern African "Creeping Aloes" ('' Mitriformes'') together with closely related species ''

Aloe perfoliata ''Aloe perfoliata'', the rubble aloe or mitre aloe, is a hardy creeping aloe, found in rocky, mountainous areas throughout the Western Cape, South Africa. Naming and classification ''Aloe perfoliata'' was formerly known as ''Aloe mitriformis''. ...

'', '' Aloe arenicola'', '' Aloe meyeri'' and '' Aloe dabenorisana''. However, other botanists believe it to be closer to the "Climbing Aloes" ('' Macrifoliae''). This unusual plant would be an outlier whichever series it was classified into, and is probably a "missing-link" intermediate between the two series. The name ''"pearsonii"'' remembers the botanist and first director of the South African National Botanical Institute, Professor Pearson.

Appearance

Z Aloe pearsonii - Stellenbosch botanical gardens 2

This aloe grows a clump of rigidly erect stems, that are covered in four highly symmetrical rows of thick re-curved leaves. In the dryer months the plants are red, while during times of rain the leaves fatten and turn blue-green. Pearson's aloe flowers in summer, and especially in January–February, producing a multi-branched

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

covered in bright red or yellow flowers. Of all the aloes, this species is the slowest growing. In spite of this, plants have been found in the wild with heights of over 2 meters. Such individuals are believed to be several hundred years old.

Habitat

This aloe occurs in groups in sandy patches of the rocky Richtersveld mountains. It is found in some of the hottest and driest parts of this area. Rain is very rare, and generally only during the winter months. It is possible that the plant receives some moisture from the mists that periodically sweep the mountainsides.

Conservation status

''Aloe pearsonii'' formerly occurred in dense stands prior to 2010 and classified as Least Concern on the

South African National Biodiversity Institute The South African National Biodiversity Institute (SANBI) is an organisation tasked with research and dissemination of information on biodiversity, and legally mandated to contribute to the management of the country's biodiversity resources. ...

's Red list of South African plants. However, severe population declines occurred between 2015-2020 due to an extended drought throughout its range, with declines of more than half across all subpopulations, and due to this species' very low recruitment, it is now considered

Critically Endangered An IUCN Red List critically endangered (CR or sometimes CE) species is one that has been categorized by the International Union for Conservation of Nature as facing an extremely high risk of extinction in the wild. As of December 2023, of t ...

by the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological ...

. Suitable habitat for this species is predicted to decline by 80-100% by 2080 due to

climate change Present-day climate change includes both global warming—the ongoing increase in Global surface temperature, global average temperature—and its wider effects on Earth's climate system. Climate variability and change, Climate change in ...

. It is also threatened by

habitat destruction Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

from livestock farming and consumption by livestock and native herbivores due to

overgrazing Overgrazing occurs when plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods. It can be caused by either livestock in poorly managed agricultural applications, game reserves, or nature ...

of other food plants.

References

* {{Taxonbar, from=Q145910 pearsonii Flora of the Cape Provinces Flora of Namibia Endangered flora of Africa