Notes on three aloes of Malawi: Aloe cam's, A. lateritia, and A. suffulta (Asphodelaceae subfam. Alooideae)
Author
Thiede, Joachim
0000-0002-0130-8424
Schenefelder Holt 3, 22589 Hamburg, Germany
joachim_thiede@gmx.de
Author
Campbell-Barker, Theo Peter
22 Faringdon Avenue, Lutterworth LE 17 4 DJ, England (email: theo. cb @ talktalk. net).
theo.cb@talktalk.net
Author
Hargreaves, Bruce J.
5817 Pryor Street, Bakersfield, CA 93308, USA
brucejhargreaves@hotmail.com
Author
Smith, Gideon F.
0000-0002-5417-9208
Department of Botany, P. O. Box 77000, Nelson Mandela University, Port Elizabeth, 6031 South Africa
smithgideon1@gmail.com
Author
Figueiredo, Estrela
0000-0002-8511-8213
Department of Botany, P. O. Box 77000, Nelson Mandela University, Port Elizabeth, 6031 South Africa
epnfigueiredo@gmail.com
text
Bradleya
2020
2020-06-26
38
247
253
https://www.mendeley.com/catalogue/8fe3b13d-ffa9-34d8-a569-ada13d0ae5ad/
journal article
10.25223/brad.n38.2020.a23
69b0526e-7e3a-401d-8bea-b8a2541c1f36
7871694
Aloe canis
S.Lane
Aloe canis
was discovered by one of us (TPC-B) in the 1970s on the northern slopes of the Senga Hills near Senga at the shore of Lake Malawi (Salima District, Central Province;
Figure 1
: 1a). He collected two living plants that were at first thought to represent
A. cameronii
and observed two further plants on fairly level rocky ground somewhat inland from Domira Bay northwest of Senga (
Figure 1
: 1b), and a single further plant adjacent to a small, dry, seasonal riverbed on a slope of the Ntchisi Hills (
Figure 1
: 1c). The identity of plants observed at a distance with a pair of standard binoculars on the escarpment of the Angoni highlands remains uncertain (
Campbell-Barker, 2012: 21–22
). Campbell-Barker cultivated the two living plants for many years in Blantyre (the largest city in Malawi;
Figures 2
& 3). After his return to England, the plants came into the possession of Reverend Stewart Lane at Limbe, Malawi, who noted their distinctness and described the taxon as a new species
A. canis
(as “
A. canii
”), the epithet alluding to Campbell-Barker (Latin
canis
= dog;
Lane, 2001
;
Lane
et al.
, 2003
).
When Lane left Malawi, one
A. canis
plant remained in the private garden of Ms Ruth Mthawanji, in Newlands, Blantyre, Malawi, and 50 seeds were distributed to a grower in South Africa which did not germinate and were likely of hybrid origin (G. Hayes, personal communication by e-mail on
16 June 2015
and on
17 January 2020
to one of us (
JT
)). The plant in the domestic garden of Mthawanji is still in cultivation (S. Lane, personal communication by e-mail on
10 January 2020
to one of us (
GFS
)), which was confirmed by Mthawanji (personal communication by e-mail on
16 January 2020
to one of us (
GFS
)). Mthawanji noted that the plant was indeed given to her by Reverend Lane some 20 years ago (i.e.,
ca
. early-2000s) and that it has flowered regularly (
Figures 4
&
5
) but has not produced fertile seed so far, likely because the species is self-sterile, as are most aloes and their generic kin. The plant does not produce suckers and it has not been possible to propagate it vegetatively. Lane (personal communication by e-mail on
16 January 2020
to one of us (
GFS
)) notes that Mthawanji’s propagation experience with
A. canis
is congruent with what he found, i.e., that the specimen he gave to Mthawanji, and likely the species in general, does not produce suckers and no or almost no viable seed, at least when not cross fertilised. His only success at propagating the species was by cutting the stem off, which resulted in the development of a few sprouts at the cut.
F
igure 3.
Raceme of one of the two originally collected plants of
Aloe canis
flowering in cultivation in Blantyre, Malawi.
Figure 4.
The specimen of
Aloe canis
that Ms Ruth Mthawanji received from Reverend Stewart Lane in the early-2000s photographed in Blantyre, Malawi, in 2015. Photograph: R. Mthawanji.
Photograph: Pastor Theo Peter Campbell-Barker.
The stem height, given by
Lane (2001)
as up to
2.5m
, should be corrected to about
1.5m
(
Campbell-Barker, 2012: 25
). In habitat, it appeared that some of the single-stemmed plants had wounds on the stem indicating that offsets may have been removed (
Campbell-Barker, 2012: 21
).
The distribution area of
A. canis
in Malawi has been virtually denuded of all plants of
Aloe
(
Lane, 2004: 38
); these were collected for various uses by the local inhabitants, especially as an ineffective treatment of AIDS by traditional healers (“singangas” in the local language;
Campbell-Barker, 2012: 26
). One of us (
JT
) explored the westernmost of the Senga Hills on
20 April 1991
, but did not find any plants of
Aloe
(
Thiede, 1993: 31
;
Thiede & Campbell-Barker, 2015: 29
). All attempts by several people to relocate the species failed and it is thought to now be extinct in the wild in Malawi (
Lane, 2004: 38–39
). Recently what appears to be the same species has been found in Mozambique just across Lake Malawi from its [possibly] former location in Malawi (S. Lane, personal communication by e-mail on
10 January 2020
to one of us (
GFS
)).
Figure 6.
Aloe lateritia
var.
lateritia
in habitat in northernmost Malawi at Ipenza Village in July 1968. The spotted leaves can reach a length of 45cm (18’’), but grow much longer in cultivation when irrigated throughout the year (
Hargreaves, 1975: 92
) (published earlier in
Hargreaves, 1975
: Figure 4).
Figure 5.
Panicle of the specimen of
Aloe canis
that Ms Ruth Mthawanji received from Reverend Stewart Lane photographed in Blantyre, Malawi, in 2019.
Photograph: R. Mthawanji.
Photograph: Bruce J. Hargreaves.
Aloe canis
was first considered to be a variant of
A. cameronii
, which it resembles, but it is generally larger, usually single-stemmed, and has denser rosettes with a few scattered maculations on both leaf surfaces near the leaf base (
Carter
et al
., 2011: 637
); it might well have arisen as a spontaneous natural hybrid [or allopolyploid; JT] involving
A. cameronii
and a second species (Hayes, 2015). The
type
of the name
Aloe canis
,
Lane 1
, is recorded as deposited at Herb.
MAL
(
holotype
) and Herb.
PRE
(isotype). Neither of these specimens is available for examination online.