Deidamia thompsoniana DC., Prodr.

Gautier, Laurent & Callmander, Martin W., 2021, A synoptic revision of the genus Deidamia (Passifloraceae), Candollea 76 (2), pp. 293-297 : 296-297

3. Deidamia thompsoniana DC., Prodr. 3: 337. 1828 ( Fig. 2 ).

– Passiflora octandra J.V. Thomps. ex DC. [nom. illeg.].

– Thompsonia browniana M. Roem., Fam. Nat. Syn. Monogr. 2: 138. 1846 [nom. illeg.].

Holotypus: MADAGASCAR: sine loco, s.d., Thompson s.n. ( BM [ BM000902557 ] image!; iso-: G-DC [ G00659429 ]!) .

= Deidamia bicolor H. Perrier in Notul. Syst. (Paris) 9: 62. 1940, syn. nov. Lectotypus (designated here): MADAGASCAR. Reg. Alaotra-Mangoro: Analamazoatra , X.1914, Perrier de la Bâthie 5284 (P [ P00137324 ]!). Syntypus: MADAGASCAR. Reg. Alaotra-Mangoro: Nord d’Anosibe, aux env. de Moramanga, 17.II.1930, Decary 7174 (P [ P04766810 ]!); sine loco, VII.1884, Curtis s.n. (K image!).

[Ramahenina 127] [Picture: © R. Randrianaivo]

Distribution and ecology. – Deidamia thompsoniana is distributed along the eastern escarpment of Madagascar, from Masoala southward to Manombo, as well as in the Sambirano, between 100 and 1100 m in sub-humid and humid bioclimatic zones. It is a liana recorded to reach a basal diameter of more than 5 cm ( PERRIER DE LA BÂTHIE, 1945) and to grow up to 20 m long (but likely longer), in lowland to medium altitude moist evergreen and semi-evergreen forests, often collected in secondary environments and forest margins.

Conservation status. – With an EOO of 109,261 km ² and an AOO of 104 km ² (which could qualify for Endangered under criterion B), Deidamia thompsoniana is known from 18 locations with respect to the most plausible threat which is habitat destruction for agriculture. Eight of these locations are within the protected areas network (Analamazaotra, Betampona, Corridor Ankeniheny-Zahamena, Mantadia, Mangabe-Ranomena-Sahasarotra, Masoala, Ranomafana and Torotorofotsy); however, no decline can be inferred as the species apparently thrives in secondary environments. It is therefore assessed as “Least Concern” [LC] ( IUCN, 2012).

Notes. – Deidamia thompsoniana was based on an unnumbered Thompson collection from Madagascar deposited in the Lambert herbarium cited as “in herb. Lamb. (v.s.)” by CANDOLLE (1828: 337). The herbarium of Ayhner Bourke Lambert (1761–1842), a British botanist, was sold at auction after his death divided into 317 lots and bought by 16 buyers ( MILLER, 1970). Candolle visited Lambert in 1816 and consulted his herbarium (CANDOLLE, 2014). Following this visit, Candolle received 100 miscellaneous specimens from Lambert in 1819 (CANDOLLE, 1830); among this material there was a fragment of Thompson s.n., which is now in G-DC, while the original specimen is deposited in BM. We consider that Candolle saw the BM specimen during his consultation of Lambert herbarium and therefore that it represents the holotype of D. thompsoniana as cited by MASTERS (1875: 162). The fragment at G is an isotype.

Probably because he had no access to the type, PERRIER DE LA BÂTHIE (1940, 1945) erroneously treated Deidamia thompsoniana as a synonym of D. commersoniana . To accomodate the very distinctive specimens with coriaceous, discolorous leaves, dark green adaxially and reddish-brown abaxially, he described D. bicolor . We therefore consider D. bicolor as a synonym of D. thompsoniana . The misinterpretation of the taxonomy of these species by PERRIER DE LA BÂTHIE (1940, 1945) can best be explained by the fact that he never saw the original material of D. thompsoniana either in BM or G, and his understanding of the species was based only on the brief Latin diagnoses by CANDOLLE (1828: 337).

Deidamia bicolor was described on the basis of two syntypes and the best-preserved specimen, Perrier de la Bâthie 5284, is designated here as the lectotype.

Figures

Fig.2. – Flowers of Deidamia thompsoniana DC.