Dracaena tholloniana Hua

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 : 44-45

20. Dracaena tholloniana Hua — Map 19

Dracaena tholloniana Hua (1897) 662. — Type: Thollon 91 (holo P ( P00442286 ); iso K-fragment & drawing ( K000255934 ), P ( P00442285 )), Gabon, Ogooué , N’Djolé, Jan. 1895.

Dracaena longipetiolata Mwachala & Eb.Fisch. (2013) 442. — Type: Hallé & Villiers 5362 (holo P [ P02058236 ]), Gabon, Monts de Cristal , 12 km SW de Kinguélé, 18 Feb. 1966, syn. nov.

Dracaena monostachya Baker var. angolensis Baker (1898) 447. — Lecto- type (designated by Bos 1984): Welwitsch 3745 (lecto BM [BM000911609]), Angola, Golungo Alto, Apr. 1856, syn. nov.

Distribution — Cameroon, Gabon, Republic of the Congo,

Democratic Republic of the Congo, Angola.

Notes — Dracaena tholloniana is very similar to D. aubryana Brongn. ex É.Morren and are synonyms according to Bos (1984). Dracaena tholloniana is reinstated here, because it differs from D. aubryana in having flowers of only 8–13 mm long, subtended by 0.5–1 mm long bracts. Dracaena aubryana has flowers 23–38 mm long, with bracts of 1–1.5 mm long.

The protologue of D. tholloniana cites Thollon 31 as the type and states ‘Ndjolé, sur le haut Ogooué, sous-bois, fl. Janvier 1895 ’. However, at P, Thollon 31 represents an Asteraceae ( Eclipta prostrata (L.) L.) with a different date and location. Both Bos (1992) and Mwachala & Mbugua (2007) cite Thollon 91 as the holotype for D. tholloniana but give no reason for this change in number. They probably, as we, assume it was a printing error. There are two duplicates of Thollon 91 at P (P00442286, P00442285), the specimen with barcode P00442286 matches the locality data and collecting date mentioned in the protologue and is annotated ‘ Dracaena tholloniana Hua’ in Hua’s handwriting.

Dracaena longipetiolata was described from a fruiting specimen with a long petiole. However, such long petioles are also found in specimens otherwise perfectly fitting within D. tholloniana , while intermediates also exist. Furthermore, the infructescence also fits within the range of D. tholloniana . Therefore, we do not recognise this form as a distinct taxon.

According to Bos (1984), Dracaena monostachya var. angolensis is synonym of D. aubryana s.lat. It was described from

Map 19 Distribution of Dracaena tholloniana Hua.

a plant with a short peduncle and leaves with a rounded base and long petiole. These characters fit those of D. tholloniana , as does the lectotype chosen earlier by Bos.