Magnolia occurring

Brambach, F., Nooteboom, H. P. & Culmsee, H., 2013, Magnolia sulawesiana described, and a key to the species of Magnolia (Magnoliaceae) occurring in Sulawesi, Blumea 58 (3), pp. 271-276 : 274-275

Key to the species of Magnolia occurring in Sulawesi

The following key does not differentiate between the two varie- ties of M. carsonii found in Sulawesi, M. carsonii var. carsonii and M. carsonii var. phaulanta (Dandy ex Noot.) S.Kim & Noot. As Nooteboom (1988) already pointed out, the two are very similar, possibly conspecific, and can only be differentiated by quantitative characters. The difference in leaf size ( Kim et al. 2002) could not be confirmed for specimens from Sulawesi and Borneo present in the collections in L and BO, leaving slight differences in flower size (cluster of perianth and stamen scars 2–3 mm vs c. 1 mm long) as the only separating character. We therefore prefer to treat all collections from Sulawesi as M. carsonii var. carsonii .

Within Sulawesi and its satellite islands M. angatensis is only known from one sterile collection on Talaud Island (Lam 3121, L), midway between the north-eastern tip of Sulawesi and the Philippine island of Mindanao. Distinction between the many forms of M. liliifera and M. angatensis based on sterile material is nearly impossible. We do not treat the latter species separately in the key, because it would key out together with M. liliifera .

The key is mostly based on vegetative characters for easy identification in the field. Information on distribution (geography and elevation) is based on available material (from BO, CEB, GOET, K, L and U). All species known to occur on the island of Sulawesi and surrounding minor islands (e.g. Kabaena, Buton, Sangihe and Talaud) as defined in Brummitt (2001) are included. It is intended to work for specimens from Sulawesi and may not cover intraspecific variation found on other Malesian islands. Leaf measurements are given for mature trees unless indicated otherwise; young trees and adventitious shoots may have larger leaves.

See the Identification List for complete binomials with author names.

1. Stipules adnate to the petiole. In older or fallen leaves visible by a scar on the upper side of the petiole............ 2

1. Stipules free. Petioles without a scar on the upper side. 6

2. Young twigs, stipules and peduncles glabrous or with minute adpressed hairs (hardly visible with a handlens). Stipule scar up to half the petiole length. Flowers terminal on leafy twigs........................................ 3

2. Young twigs, stipules and peduncles usually conspicuously hairy (sometimes glabrous or glabrescent). Stipule scar about half to the full length of the petiole. Flowers terminal on leafy twigs or on axillary short shoots................... 4

3. Stipule scar up to one third the petiole length (rarely up to half the length). Fruits ellipsoid or ovoid, only slightly longer than wide. Carpels opening first along the ventral suture. — Widespread, 1000–1500 m .......................................... M. sumatrana var. glauca

3. Stipule scar one third to half the petiole length. Fruits cylindri- cal, 2–3 times as long as broad. Carpels opening first along the dorsal suture. — C and SE Sulawesi, rare, 800–1200 m ........................................ M. utilis

4. Leaves c. 9–22 cm long, lanceolate, the widest part of the blade always beneath the middle. Petiole base not or only slightly thickened. Young twigs with numerous conspicuous white lenticels. Branching monopodial, internodes evenly spaced, flowers terminal on axillary short shoots. Cultivated, 0–1000 m .............. M. champaca var. champaca

4. Leaves c. 9–42 cm long, narrowly elliptic to elliptic (to oblanceolate), the widest part of the blade close to the middle or above it. Young twigs with few, dark, or no lenticels. Branching sympodial, internodes often conspicuously varying in length along twigs. Flowers terminal on normal leafy twigs. Occurring naturally, 0 – 2000 m .................... 5

5. Young twigs, stipules and underside of leaf blades woolly hairy, the hairs curled like pigs’ tails, coming off in patches, usually ± persistent on midrib and lateral veins of leaf undersurfaces. — N peninsula of Sulawesi, once recorded at 150 m. ..................................... M. villosa

5. Young twigs, stipules and underside of leaf blades glabrous or silky hairy, the hairs, if present, adpressed and straight (sometimes mixed with minute curled hairs), persistent or not. — Widespread and variable, 0–2000 m ........................................ M. liliifera var. liliifera

6. Young twigs and outside of stipules hairy (or twigs glabrous, but then stipules at least hairy outside at the very tip). Most leaves> 15 cm long. Carpels> 40 per flower. — Widespread and common, 0–1300 m ......................... 7

6. Young twigs and outside of stipules completely glabrous. Most leaves 3–12 cm long. Carpels <20 per flower. — Central part of Sulawesi, 750–2200 m ................. 8

7. Leaves narrowly oblong, narrowly ovate or lanceolate (index 2.2–4.2). Leaf undersurface glaucous, densely adpressed hairy (sometimes hairs very small and hardly visible with a handlens). Young twigs and stipules usually with short (≤ 1 mm long), adpressed hairs. Mature fruits with free carpels, each carpel opening by a longitudinal slit. — 0–1300 m ..................... M. tsiampacca var. tsiampacca

7. Leaves (ob)ovate to elliptic (index 1.7–2.3, in juveniles often oblanceolate). Leaf undersurface not glaucous, glabrous, with scattered short hairs, or with long, curled hairs. Young twigs and stipules glabrous except for the stipule tip or with long (c. 2 mm), yellow hairs. Mature fruits with carpels united, the outer parts breaking off in irregular masses. — 0–1100 m ................................... M. vrieseana

8. Leaves completely glabrous, chartaceous to thin-coriaceous, lateral veins 8–15 per side. Young twigs with few or no lenticels. Flowers terminal on leafy twigs, appearing leaf-opposed due to sympodial vegetative growth. — 1200–2000 m .............................. M. carsonii var. carsonii

8. Leaves with a line of hairs in the adaxial petiole groove and on the leaf undersurface on both sides of the midrib (hairs lost in older leaves), otherwise glabrous, coriaceous, lateral veins 13–20 per side. Young twigs conspicuously lenticellate. Flowers on axillary brachyblasts (rarely terminal). — 1600–2200 m ................ M. sulawesiana