Colea labatii Callm. & Phillipson, 2012

Callmander, Martin W. & Phillipson, Peter B., 2012, Two new species of Colea Bojer ex Meisn. (Bignoniaceae) endemic to Madagascar, Adansonia (3) 34 (1), pp. 115-122 : 118-119

Colea labatii Callm. & Phillipson , sp. nov.

( Figs 2 ; 4B, C )

Haec species a congeneris foliis glabris, foliolis papyraceis ovatis ellipticisve abaxialiter semper glandulis depressis in sicco nigris dispersis, floribus bilabiatis atque corolla alba roseave intus porcis luteis e sinibus ad tubi basim currentibus distinguitur.

TYPUS. — Madagascar. Prov. Antsiranana, DIANA, Matsaborimanga, Ankarana AP , 300-600 m au N du Camp des Anglais, 12°54’41”S, 49°06’31”E, 180 m, 22.XI.1996, Labat, Randrianjohany & Andrianantoanina 2805 (holo-, P [ P00078766 ]! ; iso-, G [ G00303498 ]!, K, MO, P [ P00568735 ]!, TAN, WAG).

Colea barbatula H. Perrier var. ambrensis H. Perrier , num. nud., sine descr.Latin, Annales de l’Institut Botanico-Géologique Colonial de Marseille sér 5, 6: 48 (1938a).

PARATYPI. — Madagascar. Prov. Antsiranana, DIANA, massif de l’Ankarana, tsingy du lac Vert [12°55’21”S, 49°05’12”E], fl., 12.XI.2003, Allorge 2764 ( P). — Ankarana AP, piste vers le lac vert, à partir de la plaque de Tsingy , 12°54’S, 49°06’E 180 m, fl., 19.II.1994, Andrianarisata et al. 31 ( MO, P, TAN). — Matsaborimanga, Ankarana AP, piste Grim , 12°53’09”S, 49°06’40”E, fl., 23.X.1997, Bardot-Vaucoulon & Andrianantoanina 855 ( G, K, MO, P [ P00309611 , P00309610 ], TAN). — Matsaborimanga, Ankarana AP, 12°56’29”S, 49°06’53”E, fl. & fr., 11.XII.1997, Bardot-Vaucoulon & Andrianantoanina 1061 ( P [ P00309609 ]). — Misoromahalana, village de Marovato-Anketraka, forêt de Misoromahalana, 200 m [12°48’30’’S, 49°09’00’’E], imm. fr., 25.I.1960, Cours & Humbert 5438 ( P). — Forêt d’Ambatomamo, au S d’Anivorano-Nord [12°51’S, 49°15’E], fl., 30.I.1960, Humbert 32361 ( P). — Ankarana PA, in Grand Canyon, on west-central side of forest, 12°51’S, 49°07’E, 150 m, fl., 25.XI.1989, McPherson 14542 ( MO [MO-021784]). — Ankarana AP, 12°51’S, 49°04’E, 100-200 m, fl., 22-26.XI.1992, Malcomber et al. 1824 ( MO, P, WIS [ WIS0257559 ]). — Montagne d’Ambre, bord des torrents, basaltes [12°26’S, 49°12’E], fl., XI.1909, Perrier de la Bâthie 10346 ( P). — Vestige forestier, sur basaltes, près de Marovato, au nord de l’Ankarana, [12°48’S, 49°09’E], fl, 9.II.1966, Service Forestier 24562 ( P, TEF).

DESCRIPTION

Treelet 2-3 m tall. Leaves imparipinnate, 35- 40 (including petiole) × 11-22 cm; petiole 5-10 cm long, c. 2 mm diameter, glabrous, thickened at the base, verticillate on the branches, 4-5(-6) leaves per verticil, leaf scars conspicuous on the older stems; leaflets 7-13, blade ovate to elliptic, 7-12 × 3-5(-7) cm, papery, glabrous, with depressed black (when dry) glands scattered over the abaxial surface; base asymmetric, shortly attenuate; margins entire; apex acuminate, the acumen up to 1 cm long; midrib and secondary veins visible on both surfaces, prominent below; petiolule 2-5 mm, glabrous; rachis straight. Inflorescence a highly contracted raceme, cauliflorous on swollen nodules, typically with up to 15 flowers; axes with a very short glandular indument, up to 2 cm long; bracts setaceous, c. 2 × 0.2 mm, with scattered short glandular trichomes. Calyx clavate in buds, pale green (black when dry), breaking open with into 2 to 3 irregular lobes, c. 5-6 × 2 mm, glabrous. Corolla funnel-shape, white and faintly pink-tinged in bud, and obscurely 2-lipped, with five sub-equal spreading lobes, c. 1-1.5 × 0.4- 0.5 cm, finely puberulent with a whitish glandular indument outside, and with a sparse short white indument in the throat; tube gradually narrowed to c. 2 mm diameter within the calyx, with five longitudinal yellow ridges running inside from the sinuses to the base of the tube, yellow above the mouth of the calyx outside; lobes rounded c. 4-6 × 3-4 mm. Stamens 4, c. 12 mm in length; anthers c. 2 mm, 2-locular. Style 9-15 mm long. Fruit a pendant ellipsoidal indehiscent follicle, c. 6 × 1.8 cm, attenuate at the summit, surface coarsely rugose.

DISTRIBUTION AND ECOLOGY

Colea labatii sp. nov. is only known from dry forests of northern Madagascar. It grows on eroded limestone in the Ankarana region and basaltic rocks around montagne d’Ambre and Marovato (north of Ankarana).

REMARKS

Colea labatii sp. nov. is characterized by its glabrous leaves with papery ovate to elliptic leaflets, always with depressed black (when dry) glands scattered over the abaxial surface; the inflorescence is a highly contracted raceme inflorescence (up to 2 cm), cauliflorous on nodules, bearing bilabiata flowers with a white or pink-tinged corolla with yellow ridges running inside from the sinuses to the base of the tube. Perrier de la Bâthie (1938a) referred the only collection of the species available to him (Perrier de la Bâthie 10346) to C. barbatula H. Perrier , separating it from typical material of this species as C. barbatula var. ambrensis H. Perrier .This name is not accompanied by a Latin description or diagnosis and is therefore not validly published according to the ICBN Code art. 36.1 (McNeill et al. 2006). Colea labatii sp. nov. differs from C. barbatula in its densely arranged flowers (up to 15) on a short highly contracted raceme (vs a lax inflorescence with few flowers in C. barbatula ), the white flowers (vs dark pink) and the rugose ellipsoid follicule (vs verrucate and obovoid). Colea barbatula is only known from humid forests in the eastern escarpment of Madagascar far from the restricted northern distribution of C. labatii sp. nov.

ETYMOLOGY

The species epithet commemorates our colleague and friend Jean-Noël Labat, who collected the type specimen. Sadly, Jean-Noël passed away before this article was brought to press.His contribution to our knowledge of the plants of Madagascar has been significant.Perhaps best known for his major contribution to the published monograph of the legumes ( Du Puy et al. 2001), Jean-Noël also published on several other groups of plants. He led and supported numerous collaborative projects on Madagascar. His excellent collections from Madagascar, often accompanied by pictures and detailed notes, are a valuable legacy to the scientific community.

CONSERVATION STATUS

With an EOO of 228 km 2, an AOO of 63 km 2 and three subpopulations, two of which within the protected area network (Ankarana) (calculation following Callmander et al. 2007), C. labatii sp. nov. is assigned a preliminary status of Endangered [EN B1ab(iii)+B2ab(iii)] ( IUCN 2001).

Figures

FIG. 2. — Colea labatii Callm. & Phillipson, sp. nov.: A-C, Labat & al. 2805 (holotype, P), inflorescence (A), flower (B) and leaf (C); D, Bardot-Vaucoulon & Andrianantoanina 1061 (paratype, P), fruit. Scale bars: A, B, D, 1 cm; C, 2 cm.

FIG. 4. — A, Colea unifoliolata Callm. & Phillipson, sp. nov., branch, leaves and single flower (arrow), Schatz et al. 3915 (photo: G. E. Schatz); B, C, Colea labatii Callm. & Phillipson, sp. nov.; B, Bardot-Vaucoulon 1061 (photo: M. Bardot-Vaucoulon), mature fruit; C, Labat et al. 2805 (photo: J.-N. Labat), close-up of flower.