Aloe khamiesensis, Pillans

Klopper, Ronell R., Grace, Olwen M., Klopper, Arrie W., Smith, Gideon F. & Van, Abraham E., 2023, A taxonomic revision of Aloe sect. Purpurascentes (Asphodelaceae subfam. Alooideae), Phytotaxa 628 (1), pp. 1921-1935 : 1921-1935

Aloe khamiesensis and Aloe knersvlakensis

Aloe khamiesensis was described by Neville S. Pillans (1934: 25) from a specimen he collected at Kamieskroon in 1922. It occurs from Steinkopf south to the Kamiesberg (its type locality), Northern Cape, South Africa. It is also present in the Bokkeveld Mountains north of Nieuwoudtville and the Hantamsberg near Calvinia in the Northern Cape, South Africa, but is absent from Namibia. This aloe grows in mountainous country on rocky slopes and outcrops, almost exclusively on granitoid rocks (Klopper 2014). It is closely allied to A. microstigma from south-central and western South Africa and A. framesii from western South Africa ( Reynolds 1950, Carter et al. 2011). Some authors consider it to be conspecific with A. microstigma ( Glen & Hardy 2000) , while others recognise it as distinct ( Carter et al. 2011, Grace et al. 2011).

Disjunct populations between Loeriesfontein and Calvinia, Northern Cape, South Africa, were reported on by Van Wyk & Smith (1996, 2014) as an isolated form of A. khamiesensis . Reynolds (1950) also refers to unconfirmed reports of this species occurring in the Hantamsberg, Calvinia Division. One population on the plains near the farm Holrivier was visited in July 2010, but several extensive populations were witnessed on the crests of ridges further north towards Loeriesfontein. Another population is known from the Hantam National Botanical Garden near Nieuwoudtville, Northern Cape, South Africa, and specimens from Meulsteenvlei west of Nieuwoudtville are lodged at Herb. PRE (Watermeyer in Marloth 6829 & 12937). The Calvinia–Loeriesfontein plants also show close affinities to A. knersvlakensis and may be closer to the latter taxon in terms of morphology, flowering time, and geographical distribution range.

Aloe knersvlakensis was discovered and described by Sarel J. Marais (2010: 96) from the Knersvlakte. It is currently only known from its type locality near Kliprand in the Knersvlakte, Western Cape, South Africa, where it grows on north-facing quartzitic sandstone ridges and medium slopes (Klopper 2014). This aloe clearly belongs in A. sect. Purpurascentes ( Marais 2010, Carter et al. 2011). However, doubts have been raised as to its recognition at specific level. One view is that it is an outlying population and form of A. framesii (J.J. Lavranos, pers. comm.), while B. Kemble (pers. comm.) regards it as intermediate between A. microstigma and A. khamiesensis .

Species doubtfully included in Aloe sect. Purpurascentes

Aloe chlorantha was described from the Fraserburg district by John J. Lavranos (1973: 87). It is confined to an area around Fraserburg in the Northern Cape, South Africa. It commonly grows wedged among dolerite boulders on the summits and north-facing aspects of a few ridges in the upper Groot Karoo (Klopper 2014). This aloe shows morphological affinities with A. broomii Schönland (1907: 137) from central South Africa and with A. comosa Marloth & A.Berger in Berger (1905: 86) from the Western Cape, South Africa ( Lavranos 1973). It is, however, considered by some to be most closely related to A. microstigma from south-central and western South Africa ( Carter et al. 2011; J.J. Lavranos, pers. comm.). Chemistry of the leaf compounds also show affinities with both A. broomii and members of A. sect. Purpurascentes ( Van Wyk & Smith 1996, 2014, Viljoen 1999). This intermediate position in terms of both morphology and chemistry could indicate that A. chlorantha may have arisen as a hybrid between A. broomii and A. microstigma .

Aloe pictifolia was described by David S. Hardy (1976: 62) from a specimen collected by G.X. Marais from near Patensie. It is endemic to Cape sourveld vegetation in the Humansdorp area of the Eastern Cape, South Africa, where it grows on steep rocky quartzitic sandstone cliffs (Klopper 2014). The taxonomic affinities of this aloe are uncertain. Glen & Hardy (2000) includes it in Aloe sect. Echinatae Salm-Reifferscheid-Dyck (1837: 15) with its closest relative being A. krapohliana Marloth (1910: 408) from western South Africa ( Hardy 1976). On the other hand, Van Wyk & Smith (1996, 2014) and Carter et al. (2011) consider it to be closest to A. microstigma from southern and western South Africa, and other members of A. sect. Purpurascentes. Associated with this latter view, some consider it to be a form of A. microstigma that is adapted to a cremnophytic habit.