Weinmannia stenostachya Baker

Bradford, Jason C. & Miller, James S., 2001, New taxa and nomenclatural notes on the flora of the Marojejy massif, Madagascar. V. Cunoniaceae: Weinmannia, Adansonia (3) 23 (2), pp. 219-236 : 232-235

Weinmannia stenostachya Baker (species-group G)

Kew Bull. 1895: 103 (1895). — Type: Baron 6406, northern Madagascar (holo-, K!; iso-, P!) .

COLLECTIONS EXAMINED FROM MAROJEJY. — wide, elliptic to obovate, decurrent at the base for MADAGASCAR, Prov. Antsiranana: Deroin & Badré 74, 3- 7 mm, apex obtuse, margin serrulate throughrive gauche de la m Manantenina ,, versant sud du out, Beondroka, 1130 14°26’S, 49°48’E ( MO, P); teeth blunt, sinus shallow, with a small dark Miller & Randrianasolo 4456, western slopes and sum- gland, lateral veins 15-22 per leaflet, semicraspemit of Mt. Beondroka , 830-1210 m ( MO, P, TAN). dodromous, veins terminating at the sinus .

Flower-bearing axes spicate, spikes 4.5-7 cm

long, axis puberulous, usually borne in pairs from

This species is widespread in the northern, a short peduncle, 0.7-1.5 mm long, with a vegeeastern and southern uplands. See discussion tative bud between each spike (i.e. forming under W. arguta about the distinguishing features dyads), dyads borne axillary and sometimes terof W. stenostachya . minally near the distal end of stems, or spikes

occasionally borne from leaf axils along the main

stem. Floral bracts curled, ligulate, c. 1 mm long,

Weinmannia venosa J.C. Bradford , sp. nov. subtending solitary flowers that spread apically in (species-group G) a line, flowers inserted up to 3 mm from their

bract.

Frutex vel arbor 2-12 m alta. Folia plerumque 3-foli- Flowers bisexual or female?, pentamerous, olata, glabra, rhachidi non alata, foliolis lateralibus ellip- diplostemonous, sepal lobes triangular, 1- ticis, 1-4.5 cm longis, 0.8-2 cm latis, apiceum obtusis, basim acutis, margine serrulata. Inflorescentia spicata, 1.25 mm long, sparsely puberulous, petals 4.5-7 cm longa, bracteis c. 1 mm longis, subtendens green?, elliptic, 1.2-1.4 mm long, 1 mm wide, florem sessilis, singularis. Ovarium puberulum . Semina sparsely puberulous, stamens 10, filaments 2.5- comose. 3 mm long (1 mm, female flower?), floral nectary

thin, c. 0.5 mm tall, ovary ovoid, 1 mm tall,

TYPUS,. — Rakotomalaza Prov. , Ravelonarivo & Messmer densely puberulous, ovules numerous, c. 16 per

959 Madagascar. Antsiranana, Réserve Naturelle Intégrale de Marojejy , versant ouest et sud- locule, styles 1.8-2 mm long. Capsules 4-5 mm ouest du sommet de Marojejy, ouest et sud du campe- long, calyx persistent, endocarp and exocarp sepment 5, 1875 m, 14°27’S, 49°44’E, 18-19 Nov. 1996 arating in old fruits, seeds elliptic to slightly reni- (holo-, MO; iso-, TAN). form, 1.25 mm long, 0.6-0.7 mm wide, comose ,

trichomes c. 0.5-1 mm long. — Fig. 6 .

Tree or shrub, 2-12 m tall, branching every 1- few nodes, occassionally dichotomously, intern- PARATYPES. — MADAGASCAR, Prov. Antsiranana: odes 0.7-5.5 cm long, lateral branches with short Bradford & Rafamantanantsoa 719, 722, near source of

Andranomifototra river, NE of summit of Marojejy,

internodes, c. 1-2 mm long, then internodes of near “Camp 4” and forested slopes north of the camp, c. 1 cm or longer, the stems gray, cylindric, the 1520-1600 m, 14°26’24”S, 49°44’30”E ( MO, P, young growth with dense, orange pubescence. TAN); Humbert, Capuron & Cours 24726, massif de Axillary buds stipulate, stipules c. 2 mm long, l’Anjanaharibe (pentes et sommet nord) à l’ouest 2.5 mm wide, unfused, pubescent, caducous; d’Andapa (haute Andramonta, bassin de la Lokoho:

nord-est), 1600-1800 m (MO, P).— Prov. Toliara:

medial stipules caducous, inner surface glabrous, Rakotomalaza 517, Fort-Dauphin, Eminiminy, RNI outer surface pubescent, elliptic to ovate, 4-7 mm #11 Andohahela, parcelle #1, campement 4, sur la long, colletors 0.3-0.7 mm long, red-black. crête, 1500-1650 m, 24°34’S, 46°44’E (MO, P). Leaves decussate, imparipinnate, (1-)3-5(-7)-foliolate, 2.5-8.5 cm long, petiole 0.3-1.5 cm long, Weinmannia venosa is known from two disrachis not winged, both lamina surfaces glabrous junct populations at Marojejy and Andohahela in mature leaves except for pubescent midribs, more than 1500 km apart, and possibly from a young leaves sparsely pubescent on abaxial lam- third population at Andringitra (Guillaumet ina; lateral leaflets elliptic, 1-4.5 cm long, 0.8- 3388). 2 cm wide, the apex obtuse, the base concave The leaves of W. venosa resemble those of distally, convex basally, terminal leaflets slightly W. hildebrandtii ; both have prominent venation, larger than the laterals, 1.6-6 cm long, 1.3-3 cm but they differ most obviously by the number of

flowers subtended by a bract (one in W. venosa versus c. four in W. hildebrandtii ). With its spicate inflorescence, pubescent ovaries and comose seeds, W. venosa is similar to W. humblottii , W. sanguisugarum and W. arguta . However, Weinmannia venosa has fewer leaflets (usually 3) than W. sanguisugarum (c. 15). W. venosa has elliptic to obtuse leaflets that are apically obtuse, whereas leafets of W. arguta are elliptic to ovate and apically acute. In W. venosa , the leaves are generally larger than in W. humblotii , and the venation in W. venosa is more prominent than in W. humblottii . Weinmannia venosa does not have a slightly laminar rachis, which is a common feature in W. humblottii .

Bradford 722 appears to have diminuitive male organs, whereas Rakotomalaza 959 from the same population has bisexual flowers. Wart-like bumps on the leaves of Bradford 722 suggest that the plant is diseased, which may have affected floral development. Unisexual flowers are not known in Malagasy species of Weinmannia , but do occur elsewhere in the genus.

Figures

Fig. 6. — Weinmannia venosa J.C. Bradford: A, fertile branch; B, flowers; C, stipule; D, portion of spike; E, close-up of terminal leaflet. From Rakotomalaza, Ravelonarivo & Messmer 959 (TAN).