Aloe lateritia Engl. var. lateritia

Thiede, Joachim, Campbell-Barker, Theo Peter, Hargreaves, Bruce J., Smith, Gideon F. & Figueiredo, Estrela, 2020, Notes on three aloes of Malawi: Aloe cam's, A. lateritia, and A. suffulta (Asphodelaceae subfam. Alooideae), Bradleya 38, pp. 247-253 : 250-252

Aloe lateritia Engl. var. lateritia

Aloe lateritia var. lateritia , as presently circumscribed, is a maculate aloe documented by specimens from grasslands or rocky places in southern Kenya and Tanzania. Aloe lateritia var. graminicola (Reynolds) S.Carter is known from Kenya only ( Carter, 1994: 15–17, pl. 1; Carter et al., 2011: 179–180). Alarmingly, for Malawi Msekandiana & Mlangeni (2002: 34) recorded Aloe lateritia as CR B1B2cD, i.e., ‘Critically Endangered’ with a ‘Small distribution and Decline or Fluctuation’ evidently based on ‘severely fragmented’ locations or ‘known to exist at one or fewer locations’ and ‘continuing [to] decline’ in its ‘area, extent and/or quality of habitat’ with fewer than 50 ‘mature individuals’.

One of us (BJH) found Aloe lateritia var. lateritia in northernmost Malawi in 1967 at Ipenza Village near Songwe River which forms the border between Malawi and Tanzania (in Chitipa District, Northern Province; Figure 1 : 2), and revisited the locality together with Roger Royle in July 1968 ( Hargreaves, 1975: 92 and Figures 4–8 , two of these are reproduced here as Figures 6 & 7 ; Whellan, 1975: 111). Philip Downs (†) discovered a further locality in September 1991 along the track parallel to the Songwe River between the Ipenza and Chiwanga villages on the hills to the left (southern) side of the track ( Thiede et al., 2009: 228; Figure 1 : 2).

Specimens were not preserved. Since the two localities are imprecisely given as “beyond Chitipa” ( Whellan, 1975: 111), “near the Songwe River” ( Lane, 2004: 27), or “south of the Songwe River” ( Klopper et al., 2012: 87), more exact locality information is provided here to enable the collection of preserved specimens for deposition in a herbarium. As preserved specimens were not prepared, the specimen-based treatments of Aloe for the Flora of Tropical East Africa ( Carter, 1994: 15–17) and Flora zambesiaca projects ( Carter, 2001) omitted the record of Aloe lateritia var. lateritia from Malawi. In contrast, the ‘Plants of the World Online’ database ( POWO, 2019) lists “N. Malawi” as its native range.

Lane (2004: 27) and Klopper et al. (2012: 87) suggest that the plants of A. lateritia that occur near Ipenza may have been brought to Malawi by humans travelling back and forth between Malawi and Tanzania. However, the photographs of Hargreaves (1975: Fig. 4–8 , two of these are reproduced here as Figures 6 & 7 ) show plants apparently growing naturally amongst undisturbed grasses, and the locality found by Downs is beyond villages.

In the protologue of the name Aloe lateritia , Engler (1895: 140–141) cited a single collection “([TANZANIA, Moshi distr.,] Rombo ― Volk. [-ens] n. 404) ― An sandigen und steinigen Abhängen, an Felsvorsprüngen um 1400―1500m ”. [English: On sandy and stony slopes, on rock spurs around 1400– 1500m].

Two specimens are available for examination online. The holotype, cited by Reynolds (1966: 95, as “type” and on p. 96 as “ holotype ”) and by Carter (1994: 15, as “holo.”) is kept at Herb. B, Volkens 404 ( B barcode B 10 0165570 , digital image! at https://herbarium.bgbm. org/object/B100165570); a photograph of this specimen is at Herb . K (K000210270, at https://apps.kew.org/ herbcat/detailsQuery.do?imageId=&pageCode=1&present- Page=1&queryId=1&sessionId=8 F 9279 D 2 F 48866 A 08 BE 26 C 47902 AC 9 DC &barcode= K 000210270). An isotype exists at Herb. BM Volkens 404 ( BM barcode BM000911694 , digital image! at https://plants.jstor. org/stable/10.5555/al.ap.specimen.bm000911694?searchUri=filter%3Dfree_text %26so%3Dps_group_by_genus_species%2Basc%26 Query%3 DBM 000911694%26loggedin%3Dtrue).

The holotype, i.e., the Herb. B specimen, was dated as having been collected on 13 June 1893 [“ 13.6.93 ”], while the isotype, i.e., the Herb. BM specimen, carries the date “Juni [June] 1893”, with the exact day on which it was collected therefore omitted. However, since a black-and-white image of the more precisely dated holotype is affixed to the BM specimen, albeit with some plant fragments removed, we interpret the BM specimen as an isotype and not as a different gathering ( Turland et al., 2018: 16, Art. 8.2 Footnote).

Figures

Figure 1. Distribution of three Aloe species rare in Malawi: 1) A. canis (yellow dots, a = Senga Hills; b = inland from Domira Bay; c = Ntchisi Hills; Central Region); 2) A. lateritia var. lateritia (blue dot = near Ipenza, two records; Northern Region); and 3) A. suffulta (red dot = Mwabvi Wildlife Reserve; Southern Region). Placements of the dots are partly approximations. The map insert shows the position of Malawi (red) in Africa (map: Wikimedia Commons 2019; insert map: mapsof.net 2015).

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.

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.

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). Photograph: Bruce J. Hargreaves.

Figure 7. An inflorescence of Aloe lateritia var. lateritia at the locality noted in the caption of Figure 4, about 1.20m (4 feet) high (Hargreaves, 1975: 92) (published earlier in Hargreaves, 1975: Figure 5). Photograph: Bruce J. Hargreaves

Figure 8. Aloe suffulta in habitat in what is now the Mwabvi Wildlife Reserve (Malawi), growing on a river bank (rather likely of the Mwabvi River) in the dense undergrowth of bushes with the long, dry inflorescences literally ‘woven’ through the supporting bushes and emerging through the top, ca. 1970. Drawing: Pastor Theo Peter Campbell-Barker.