Perrierodendron rodoense, Lowry Ii, Porter P., Haevermans, Thomas, Labat, Jean-Noël, Schatz, George E., Leroy, Jean-François & Wolf, Anne-Elizabeth, 2000

Lowry Ii, Porter P., Haevermans, Thomas, Labat, Jean-Noël, Schatz, George E., Leroy, Jean-François & Wolf, Anne-Elizabeth, 2000, Endemic families of Madagascar. V. A synoptic revision of Eremolaena, Pentachlaena and Perrierodendron (Sarcolaenaceae), Adansonia (3) 22 (1), pp. 11-31 : 28-30

5. Perrierodendron rodoense J.-F. Leroy, Lowry, Haevermans, Labat & G.E. Schatz, sp. nov.

Arbor 10-12 m alta, usque ad 50 cm in diam. Folia petiolo 0.5-0.8(-1) cm longo, indumento stellato parce induto; lamina obovata, chartacea subcoriaceave, (2.6-) 3.2-4(–5.3) × 2.9-3.1(-5) cm, utrinque pubescentia stellata parce induta, apice obtusa rotundatave, margine integra vel subundulata, basi emarginata, nervis secundariis 6- ad 10-jugatis. Inflorescentia axillaris ex flore solitario pedunculo eramoso (0.5-) 0.9-1.4 cm longo bracteola 2-3 mm longa in ramulo nudo 0.5-1.7 cm longo portata subtento insidente constans; involucro sub anthesi undulato, 4-5 mm in diam., dense papillosostrigoso, florem solitarium ca. 2 cm in diam. includente. Flos sepalis 5, imbricatis, coriaceis, asymmetricis, ovatis usque suborbiculatis, duobus externis ca. 2 × 5 mm, tribus internis 10-12 × 8-10 mm; petalis 5, obovatis, 10- 11 × 8-10 mm, glabris, albidis, apice obtusis; staminibus 80 ad 85, caducis; ovario imperfecte biloculari in quoque loculo ovula duo vel tria gerente, subcylindrico, apice acuto, a basi usque ad styli basin dense piloso, ca. 2 × 3 mm; stylo glabro, ca. 2 mm longo. Fructus ignotus.

TYPUS. — Service Forestier (Capuron) 23095, Madagascar, Prov. Antsiranana, forêt d’Analafondro, sur sables, au pied sud-est du plateau Sahafary (bassin inférieur du Rodo), [12°37’S, 49°29’E], 27 Dec. 1963, fl. (holo-, P!; iso-, K!, MO!, P!) .

Trees 10-12 m high, to 50 cm dbh. Young twigs with very dense stellate indumentum. Leaves obovate, dark brown above, light brown below (in dry material), chartaceous to subcoriaceous, (2.6-)3.2-4(-5.3) × 2.9-3.1(-5) cm, with sparse stellate pubescence on both surfaces, apex obtuse to rounded, margins entire, slightly undulate, base emarginate, venation brochidodromous, with 6-10 pairs of alternate to subopposite secondary veins, midrib weakly channeled above, raised below; petiole 0.5-0.8(-1) cm long, with sparse stellate indumentum, adaxially canaliculate; stipules unknown, caducous, scars inconspicuous. Inflorescences axillary, flowers borne singly at the apex of an unbranched peduncle (0.5-) 0.9-1.4 cm long, with a slightly swollen base, subtended by a highly reduced leaf (bracteole) 2-3 mm long borne on a naked branchlet 0.5-1(-1.7) cm long, involucre in flower undulate, 4-5 mm in diam., densely papillate-strigose, containing a single flower ca. 2 cm in diam.; sepals 5, imbricate, coriaceous, asymmetrical, ovate to suborbicular, the 2 small external ones 2 × 5 mm, deltoid, the 3 larger ones 10-12 × 8- 10 mm, glabrous and papyraceous where covered by the adjacent sepal, densely stellate-strigose below where exposed; petals 5, contorted in opposite direction from sepals, obovate, 10-11 × 8-10 mm, glabrous, whitish, apex obtuse; extrastaminal disc cupuliform, 1 mm high, margin entire; stamens ca. 80-85, filaments ca. 5 mm long, anthers ca. 1(-1.5) × 0.5 mm, oblong, basifixed; ovary subcylindrical, densely pilose (glabrous from the base of the style), ca. 2 × 3 mm, apex truncate, with 2 incomplete locules each containing 2-3 ovules; style glabrous, ca. 2 mm. long, stigma 2.5-3 mm long, crateriform, margin distinctly undulate. Fruits unknown. — Fig. 9 .

This species is known only from the type material, collected in the lower Rodo (= Irodo) basin ( Fig. 4 ). It can be recognized by having flowers that are borne individually at the apex of an unbranched peduncle (5-)9 × 14 mm long and subtended by a highly reduced leaf (bracteole) on a short, naked branchlet.

Figures

Fig. 9. — Perrierodendron rodoense: A, flowering branch; B, leaf (adaxial surface); C, leaf (abaxial surface); D, detail of flowering pedicel; E, flower bud; F, flowers (schematic section); G, sepal; H, petal; J, gynoecium. (A-J, Service Forestier 23095).

Fig. 4. — Distributions of Perrierodendron, mapped on the simplified bioclimatic zones of Madagascar (SCHATZ in press, after CORNET 1974). P. boinense (*), P. capuronii (+), P. occidentalis (•), P. quartzitorum (Δ), P. rodoense (-).