Rhodocolea humblotiana (Baill.) Phillipson & Callm.

Phillipson, Peter B. & Callmander, Martin W., 2015, Notes on the Rhodocolea racemosa (Lam.) H. Perrier (Bignoniaceae) species complex, Candollea 70 (2), pp. 257-265 : 264

Rhodocolea humblotiana (Baill.) Phillipson & Callm. , comb. nova.

≡ Colea humblotiana Baill. in Bull. Mens. Soc. Linn. Paris 1: 687. 1889.

≡ Rhodocolea racemosa var. humblotiana (Baill.) H. Perrier in Ann. Mus. Colon. Marseille ser. 5, 6: 27. 1938.

Typus: MADAGASCAR. Prov. Toamasina: Lac Nosibé , s.d., Humblot 191 (holo-: P [ P00647473 ]!; iso-: [ P00647474 ]!).

= Colea aberrans Baill. in Bull. Mens. Soc. Linn. Paris 1: 687. 1889.

Typus: MADAGASCAR [wrongly labeled from Timor]: sine loc., s.d., Poivre s.n. (holo-: P [ P [ P00647486 ]!).

– Rhodocolea racemosa var. bernierana H. Perrier in Ann. Mus. Colon. Marseille ser. 5, 6: 27. 1938 [nom. inval.].

– Rhodocolea racemosa var. gerrardiana H. Perrier in Ann. Mus. Colon. Marseille ser. 5, 6: 27. 1938 [nom. inval.].

Observations. – Rhodocolea humblotiana differs from all other elements included in R. racemosa by Perrier de la Bâthie by its much larger leaves:> 30 cm long including the terminal leaflet (vs <20 cm) and> 20 cm wide (vs <15 cm) and proportionately larger leaflets, its generally condensed, mostly cauliflorous inflorescences (vs. lax, and mostly borne among the leaves, at least in the case of the taxa included in this article) and its large flowers. The corolla has a broadly funnel-shaped tube which is a distinctive colour outside, shading from a brown-red at the base, and in bud, through orange and eventually yellow at the mouth. Inside the throat the tube is yellow, with red nectar guides. The corolla lobes are white. Rhodocolea humblotiana occurs at low elevations along the coastline of Toamasina Province from near Brickaville in the south to near Maroantsetra. Note that the type locality of the species: Lac Nosibé, is a locality on the east coast of Madagascar near Foulpointe, and should not be confused with the island of Nosy-be, the type locality of Colea purpurascens (see below), off the north-west coast.

Rhodocolea racemosa var. gerrardiana was based on a single specimen collected by William Gerrard, who went to Madagascar in 1865, and only visited the east coast near Toamasina (Tamatave) ( DORR, 1997). Gerrard’s collection undoubtedly represents R. humblotiana . Curiously, although Perrier de la Bâthie originally identified the specimen at K in 1936 as R. racemosa var. humblotiana , he then separated it as a distinct variety in his published treatment ( PERRIER DE LA BÂTHIE 1938a, 1938b). He wrongly stated the plant to have been collected at Fort Dauphin.

We include in this species certain material that was described as Colea hispidissima Seem. The species was based on a Boivin specimen from Ile Ste Marie, and consists of a mixture of leaf material of Rhodocolea humblotiana and flowers of a species of Vitex L. ( Lamiaceae ). We have lectotypified Colea hispidissima on the flowering material ( PHILLIPSON & CALLMANDER, 2013). Similarly, vegetative material of another Boivin specimen from Ile Ste Marie of Rhodocolea humblotiana is a syntype of Colea purpurescens Seem. In this case too we have selected other material which bears flowers and leaves as the lectotype for this species in the same article.