Dracaena acaulis Baker

Damen, T. H. J., Burg, W. J. van der, Wiland-Szymańska, J. & Sosef, M. S. M., 2018, Taxonomic novelties in African Dracaena (Dracaenaceae), Blumea 63 (1), pp. 31-53 : 32-33

1. Dracaena acaulis Baker — Map 1

Dracaena acaulis Baker (1878) 252. — Lectotype (designated here): Welwitsch 3752 (lecto LISU [ LISU222113 ]; isolecto BM [ BM000911607 ], COI [ COI00100196 ]), Angola, Pungo Audongo , cataractas do rio Cuanza, July 1855.

Dracaena rubroaurantiaca De Wild. (1906) 228. — Lectotype (desig- nated here): Dewèvre 169 (lecto BR [ BR0000008807441 ]; isolecto BR [ BR0000008807458 ]), Democratic Republic of the Congo, 20 July 1895, syn. nov.

Sansevieria longifolia Welw. in sched.

Distribution — Cameroon, Gabon, Republic of the Congo,

Democratic Republic of the Congo, Angola.

Notes — The protologue of D. acaulis cites no specimen, but mentions ‘Golungo Alto, regio 2 (1000–2400 pedes) in sylvaticis editioribus et ad rivulorum latera montium de, Alta Queta. Floret Julio.’ as a reference. The specimen Welwitsch 3752 matches both the description and the reference to its locality in the protologue. There are several duplicates, but the LISU specimen is the only specimen with labels carrying all locality data of the protologue, a label in the handwriting of J.G. Baker and a plant description very similar to that published in the protologue. Therefore, this specimen has been chosen as the lectotype for D. acaulis . It is known that Welwitsch provided specimens collected on different dates and localities with the same number ( Albuquerque et al. 2009). The specimens in BM and COI carry the same date (July 1855) as the specimen in LISU and thus probably belong to the same collection and can be regarded as isolectotypes. The other duplicates in K, LISU and P, without dates, as well as those of Welwitsch 3753 (with date April 1856), are disregarded.

Dracaena rubroaurantiaca was described from a plant with the same inflorescence type and leaf shape as D. acaulis . In the protologue, De Wildeman compared D. rubroaurantiaca with Dracaena fragrans (L.) Ker Gawl only; he probably had not seen any material of D. acaulis when describing his new species.

In his unpublished PhD thesis, Mwachala (2005) selected Plate 58 published along with the protologue ( De Wildeman 1906: 228) as lectotype for D. rubroaurantiaca . In this protologue, however, De Wildemann cited: “dans les environs de Malella, 20-juillet 1895 (Alf. Dewèvre)”. In BR, two sheets of the speci- men Dewèvre 169 were found in a type folder together with Plate 58. One of the two sheets is annotated as ‘ Dracaena rubro-aurantiaca . De Wild. n.sp.’. Although there is no loca- tion written on this sheet, it is cited in Durand & Durand (1909) with the location ‘île du Congo dans les env. de Malela’, and the morphology fits the protologue. Thus, although the plate published in the protologue is part of the original material, it is preferred to select a herbarium sheet as the lectotype.

Sansevieria longifolia Welw. is an unpublished name written on labels mounted on several duplicates of Welwitsch 3752 and Welwitsch 3753.

Figures

Map 1 Distribution of Dracaena acaulis Baker.