Alstonia costata (G. Forst.) R. Br.

Alstonia costata (G. Forster) R. Brown

Echites costata G. Forster, Prod. 20. 1786b [excl. syn. Rheede]—Pancher in Cuzent, Iles Soc. Tahiti 235. 1860.—Butteaud, Fl. Tahiti. 59. 1891.

Echites corymbosa sensu G. Forster, Herb. Aus. 1797 [non Jacquin, 13. 1760].

Alstonia costata (G. Forster) R. Brown, Mem. Wern. Soc. 1:75. 1809 [1810]—Endlicher, Ann. Wien Mus. 1:175. 1836.—Guillemin, Ann. Sci. Nat., ser. 2, 7:246. 1837 [cum desc. Forster].—A. de Candolle, Prod. 8:409. 1844.—Pancher in Cuzent, Iles Soc. Tahiti 235. 1860.—Gray, Proc. Am. Acad. 5:334. 1862c.—Seemann, FI. Vit. 161. 1866.—Nadeaud, Pl. Us. Tahiti. 38. 1864; Enum. Pl. Tahiti 56. 1873.—Lanessan, Pl. Ut. Col. Franc. 865. 1886.—Drake del Castillo, Ill. Fl. Ins. Pac. 1:31, t. 10, 1886; Ill. Fl. Ins. Pac. 7:234. 1892; Fl. Polyn. Franc. 125. 1892.—Butteaud, Fl. Tahiti. 59. 1891.—Cheeseman, Trans. Linn. Soc. 6:287. 1903.—Setchell, Univ. Cal. Pub. Bot. 12:201. 1926.—Wilder, Bish. Mus. Bull. 86:88. 1931 [non Wallich Cat. no. 1649. 1828 (= A. macrophylla G. Don)].

DESCRIPTION.—Tree, 3–10 m high, glabrous. Wood white, specific gravity 0.75. Leaves opposite. Petioles 2–5 cm long, narrowly margined, enlarged at the base. Blades elliptical, varying to lanceolate, ovate, or obovate, well-developed ones averaging 13.8 × 6 (8–16.5 × 3–8) cm, cuneate or attenuate at the base, acuminate at the apex, coriaceous, shining, glabrous or with a few scattered hairs at the base of the midrib below, entire or somewhat sinuate, with 13–19 prominent lateral veins united near the margin. Inflorescence subterminal, cymose-paniculate, subcorymbose, spreading, small or becoming 12 cm high and 16 cm broad. Bracts minute. Pedicels 3–6 mm long. Bractlets ovate, obtuse to subacute, 0.75 mm long. Calyx cut almost to the base; lobes 5, ovate, 1.8–2.2 mm long, sharply acute to obtuse, imbricate. Corolla salverform, rather constantly 11 mm long, rarely 13 mm, glabrous except for the hairy throat, white, fragrant; tube 4.5 mm long (not “scarcely longer than the calyx”), slightly expanded at the middle due to the swelling of the anthers; lobes 5, linearlanceolate, 6.5–7 (–8) mm long, 2 mm wide, dextrorsely contorted. Anthers lanceolate, 1.3 mm long, acute, subsessile on the corolla tube. Nectary a minute annulus surrounding the ovary. Ovaries 2, collectively ovoid-conical, either free or coherent, 0.9 mm long, glabrous; style 0.8 mm long; stigma ovoid-conical, 0.5–0.6 mm long; ovules many, compressed, amphitropous. Follicles geminate, linear, averaging 21 (11–35) cm long, 3–4 mm wide, usually arcuate or spirally curved, occasionally straight. Seeds elliptical, thin, compressed, peltately attached, averaging 5.2 (3.5–7) mm long including appendages (the body about 3.6 mm), ciliate-fringed, the lower end with an entire blunt acumen, the upper usually notched or bifid into 2 unequal appendages, the appendages averaging 1 (0.3–2) mm long (the perfectly symmetrical seed shown in Drake del Castillo's plate with single equal appendages on each end is very rare); albumen thin; radicle superior; cotyledons oblong, flat, longer than the radicle.

Grant 4265 was collected to show the largesized leaves (38 × 21 cm) that can be produced on young nonflowering plants in shaded habitats. Grant 4123 has leaves 16.5 × 8–9 cm, inflorescence 16 × 20 cm, pedicels 5–7 mm, and corollas 15 cm long, with lobes 9 mm long, all of these dimensions being much greater than those of any other specimen seen. It shows no qualitative differences, but could easily be distinguished as a variety. These extreme dimensions are not included in the general description above.

Grant 3921 has narrowly lanceolate leaves 10–13 × 2.8–3.5 cm, suggesting a distinct species, but it is connected to A. costata by MacDaniels 1666, these two being the only collections from Tahiti-iti. The flowers of both are typical of the species. In some respects Grant 3921 is transitional to var. fragrans (q.v.), which grows in a similar environment.

St. John 17042 has short (11 cm), divaricate, horizontal, almost straight fruits identical with those of A. elliptica (q.v.), and more abruptly acuminate leaves than in typical A. costata, but the blades are large (15 × 7.5 cm).

TYPE.—Collected by Forster in Tahiti in 1773–74.

RANGE.—Society Islands and Rarotonga. Society Islands: Banks and Solander in Tahiti and Raiatea in 1769 (BM, fide Seemann); Wiles and Smith (BM, fide Seemann); Barclay in 1836–42 (BM, fide Seemann); U. S. Exploring Expedition in 1839 (fide Gray); Bidwill ca. 1850 (BM, fide Seemann).

Tahiti: Forster in 1773–1774 (BM, fide Seemann); Bertero and Moerenhout in 1831–1832 (P, fide Drake del Castillo); Hombron in 1837–1840 (P, fide Drake del Castillo); Vesco in 1847 (P, fide Drake del Castillo); Lépine 198 and 199 in 1847 (P, fide Drake del Castillo); Ribourt 46, ca. 1850 (P, fide Drake del Castillo); Nadeaud 371, alt. 800 m and above, 1856–1859 (P, fide Drake del Castillo); Quayle 57, Mt. Aorai, alt. 1100 m, 27 September 1921, flower and fruit (BISH); Quayle, Mt. Aorai, 1–3 August 1922, flower (BISH); Whitney Exp. 598, Fautaua, 7 July 1922, flower and fruit (BISH); Setchell and Parks 485, Papeari, Maara, 250 m, 25 June 1922, flower and fruit (BISH, UC); Setchell and Parks 525, Fautaua, 8 July 1922, fruit (UC); Mac Daniels 1542, 15 May 1927, flower and fruit (BISH); MacDaniels 1666, Tautira, Vaita, alt. 350 m, 12 June 1927, flower and fruit (BISH, 2 sheets); Grant 3555, Pare, Mt. Diadem, alt. 1085 m (3550 ft), ridge forest, occasional, 13 May 1930, flower and fruit (BISH, MIN); Grant 3921, Teahupoo, Mt. Ronui, Parasponia-Cyathea forest, alt. 900 m (2955 ft), 2 July 1930, flower and fruit (BISH, MIN); Grant 4123, Mataiea, Lake Vaihiria, alt. 440 m (1450 ft), Alstonia-Neonauclea forest, 7 September 1930, flower and fruit, wood specimen (BISH, MIN); Grant 4265, Papenoo, Pufau, alt. 150 m (480 ft), Hibiscus-Neonauclea forest, 23 September 1930, sterile (BISH); St. John and Fosberg 17042, Orofena, s. ridge, alt. 1250 m, 20 September 1934, flower and fruit (BISH); St. John and D. Anderson 17427, Mt. Aorai, 1100 m, 16 September 1934, flower (BISH).

Moorea: Vesco in 1847 (P, fide Drake del Castillo); Lépine in 1847 (P, fide Drake del Castillo).

Raiatea: Moore 395, Vairahi-Avera ridge, alt. 300 m, 3 December 1926, flower and fruit (BISH, MIN).

Borabora: Grant 4955, Tevaitapu, Tahuhuura, alt. 505 m (1660 ft), ridge scrub, 3 January 1931, fruit (BISH, MIN).

Rarotonga: Cheeseman in 1899 (BM?); Wilder 544, alt. 550 m (1800 ft), 15 June 1927, flower and fruit (BISH); Wilder 729, Avarua, alt. 75 m (250 ft), 15 March 1926, flower and fruit (BISH, 2 sheets).

Throughout the Society Islands, Alstonia is a rather common small tree in the middle forest zone, extending up the ridges from a minimum altitude of 750 m (250 m in the wetter districts) to a maximum of 1540 m. In the larger interior valleys it can be found at much lower elevations (150 m). The fragrance of the flowers and the long, twisted follicles make it rather conspicuous and it seems more abundant than it really is. It is one of the dominant trees in the elfin ridge forest, where it averages about 3 m in height. Its most frequent dominant associates are, in order of abundance, Weinmannia parviflora, Metrosideros collina, Freycinetia, Vaccinium cereum, Ilex taitensis, and Styphelia pomarae.

The two Rarotongan specimens seen seem to agree in all particulars with the Tahitian plant. Wilder 729, at low altitude has leaves 13–16 × 7.5–8.7 cm, corollas 11 mm long with lobes 6 mm, fruits 29 cm, seeds 6 mm overall, with appendages to 1 mm. His other collection, at high (for Rarotonga) altitude (550 m) has identical flowers but exhibits the reduced leaves (10 × 5.5 cm) and shorter (15 cm) straight follicles of the Tahitian plants of higher elevations (cf. A. elliptica below).

Christophersen (1935:180) has suggested that one of his collections (3540) may be A. costata. Grant saw this Samoan specimen, and the suggestion is possibly correct, but the flowers are immature, no fruits are present, and it is accordingly indeterminable. There are 4 other species in this genus known from Samoa, and Christophersen 3540 might well be one of them. (We are not acquainted with A. godeffroyi Reinecke).

Gillespie has determined four of his collections from Fiji in the Bishop Museum as A. costata (Gillespie 3165, 4836, 4569, and 4549). The first three appear to be A. reineckiana Lauterbach, and the last A. plumosa Labillardière; see the remarks on these two species under A. elliptica below.

ETHNOBOTANY.—Tahitian: atache, variously misspelled as attache (Banks ex Endlicher) and atae (Pancher), the latter being the name of Erythrina orientalis. G. Forster (in Guillemin, 1837:246) also reports ahimara (ahi is Santalum, and mara is Neonauclea: there is also a variety of Santahim called ahimarea). Nadeaud (1873:84) adds napau (miscopied by Butteaud as napao). Grant 3921 was termed papaihone by Nadeaud's grandson, Tu T. Nadeaud. Pancher reports manono, but this is due to confusion by him with certain Euphorbiaceae such as Glochidion. Similarly, Drake del Castillo (1892:125) lists utureva (which is hutureva, i.e., Cerbera manghas) and afairetou, which last is presumably a misspelling of a place name in Moorea (Afareaitu) from whence were secured some of Vesco's and Lépine's specimens cited by Drake del Castillo (1892:126). He apparently mistook the locality label for a native name.

The only native use of this species we have heard of is for stomach complications associated with elephantiasis (Nadeaud, 1864).

Alstonia elliptica Moore

Alstonia elliptica Moore, Bish. Mus. Bull. 102:39. 1933.

DESCRIPTION.—Low shrub, to 1 m high. Petioles 1–2 cm long. Blades elliptical, rarely slightly obovate, 5–9 × 2–3.5 cm, rounded to acute at the tip, occasionally short acuminate. Inflorescence usually 4–5 cm high and 8 cm wide, though becoming 12 cm high on the type sheet. Calyx lobes obtuse to rounded. Corolla tube 4.7 mm long, lobes 7–8 mm long and 2.5–2.7 mm wide. Follicles 10–12 cm long, 3 mm thick, straight, usually divaricate and approximately horizontal. Otherwise as in A. costata.

The other differences given by Moore to distinguish this species from A. costata do not hold in the light of the fuller material available. The leaves do not always have “fewer (12–14) secondary nerves” as even in the type-material they may go up to 20, and in the other collections cited below they average 14–15, while the average in A. costata is 13–16. The corollas are not definitely larger, being 12–13 mm long, while 11–13 (–15) mm in A. costata. The calyx is evenly imbricated and the seeds are elliptical in each. A detailed comparison of Moore's description of A. elliptica with the description given above of A. costata, will, however, bring out other apparent differences between the two, and accordingly the following points, determined from the type-material of A. elliptica (including two isotype sheets as well as the type), and confirmed from examination of three other collections, including flowers put up in fixative at the time of collection, are here listed: pedicels averaging 5 cm long; calyx lobes 1.8 mm long; ovary ovoid (not ellipsoidal), 0.9 mm long; style 0.8 mm long; stigma 0.5 mm long; seeds averaging 3.5 × 1.5 mm and appendaged at each end, the “emarginate” condition being due to the bifurcation of the upper appendage.

This species is presumed to be a typical Mt. Temehani reduction (cf. Vaccinium, Styphelia, Rapanea, etc.) of A. costata, all of the important differences being ones of size, except for the blunter leaf tips, which, however, are far from constantly so, and the broader corolla lobes, and all of them, without exception, comparable to the phenomena associated with alpine dwarfing in boreal regions. The highest altitude collection of A. costata from Tahiti shows fruits identical with this form (St. John 17042, q.v.), and very similar types are cited above from the Marquesas and Rarotonga. We doubt if the species has any validity from a genetic standpoint, but morphologically it is very distinct, instantly recognizable both in the field and in the herbarium, and is accordingly maintained.

From a purely morphological standpoint, however, its closest relationship is not to A. costata, but to A, plumosa Labillardière, described from New Caledonia, of which we have seen no authentic material. Drake del Castillo (1886–1892: 31–32) who had seen the type of A. plumosa, says that it differs from A. costata in having nonacuminate leaves, obtuse corolla lobes which are hairy within, and narrower seeds with longer appendages. Of these differences only the seed character would separate A. plumosa from A. elliptica. Grant saw 15 collections of “A. plumosa” from Fiji, but did not know if it is really conspecific with Labillardière's plant, especially since Turrill (1915) has described A. montana from Fiji which appears to differ little from A. plumosa. In the Fiji material these long appendages (1–2 mm) seem to differentiate the two species, though we cannot separate them on the leaves alone. Kew has distributed material from Fiji which Grant took to be A. plumosa since A. reineckiana Lauterbach has even longer appendages on the seeds (Tolhill 396, 427, and 475). Alstonia plumosa apparently does not occur in Samoa, though Christophersen's “A. aff. plumosa” (1935:177) is a closely related species which was also collected by Vaupel in 1905 and distributed as “A. aff. costata.”

RANGE.—Society Islands: Raiatea, Mt. Temehani: Moore 746, alt. 600 m, red clay soil, 16 April 1927, flower and fruit (BISH, type; MIN); Grant 5205, Vaiumete, alt. 500 m (1650 ft), ridge scrub, 29 January 1931, flower and fruit (BISH, MIN); Grant 5225, Te Apoo, alt. 585 m (1920 ft), ridge scrub, 29 January 1931, flower and fruit, flowers fixed (BISH, MIN); St. John 17252, alt. 600 m, high moor, 5 October 1934, flower (BISH).

Alstonia costata var. fragrans (Moore) Grant

Alstonia fragrans Moore, Bish. Mus. Bull. 102:39. 1933.

DESCRIPTION.—Differs from the typical form in the somewhat shorter and narrower blades (9–12 × 2.5–5 cm), shorter petioles (1.5–3 cm), and the more rounded calyx lobes.

Moore lists a number of other differences between his species and A. costata but they are not constant enough to be serviceable. The relative acumination of the blades, the length of the style (0.8 mm), the width of the corolla lobes (2 mm), and the shape of the ovary (ovoid, 0.8–1 mm long) are just as in A. costata. The sepals, however, are not only “obtuse” but may actually be rounded at the apex, while they are acute to obtuse in the species proper. They are the same length in each (1.8–2.1 mm).

The plant is a tree, 3 m high. The leaves may be elliptic to oblanceolate or obovate, and are abruptly acuminate. There are 18 lateral veins both on the type-specimen and in my own collection, but part of the type-material shows 12–13 veins. Mature corollas are 11–12 mm long. The follicles are 21–25 × 0.3–0.4 cm, with seeds elliptical, about 4 × 1.5 cm, appendaged just as in A. costata.

This variety is of interest principally as representing a transition between A. costata and A. elliptica (with reference to the shape of the leaf), being known only from near the habitat of the latter. We do not suspect hybridization, inasmuch as we interpret A. elliptica (q.v.) as an ecological species rather than a genetically determined one.

RANGE.—Society Islands: Raiatea: Moore 84, east of Mt. Temehani, alt. 350 m, 16 September 1929, flower and fruit (BISH, type; MIN); Grant 5198, Mt. Temehani, alt 435 m (1430 ft), ridge scrub, 29 January 1931, flower and fruit (BISH, MIN).

Alstonia marquisensis Grant

Alstonia marquisensis Grant, in Fosberg and Sachet, Micronesica 8:46, 1972.

Alstonia coslala sensu F. Brown, Flora, 233, 1935 [non (Forster) R. Brown, 1810].

Leaves broad, elliptic or oval, obtuse to acute, 9–13 × 3.5–7.5 cm, secondary veins 13–20 on a side, strong, connected at margin by a marginal vein that arches between adjacent secondary veins, glabrous or almost so; petiole about 4 cm long; corolla white 11–13 mm long, with lobes to about 6 mm long, obtuse to acute; style 2.5 mm long; follicles 19–29 cm long, 4–5 mm wide; seed 7–9 mm long, proximal appendage frequently forked.

This species is conspicuously variable in size and shape of leaves, size of cymes and length of follicles. It is perhaps too close to A. costata R. Brown of the Society and Cook Islands. A component of montane forest on high ridges on the larger islands.

SPECIMENS SEEN.—Marquesas Islands: s.l. Henry 6 (P).

Nukuhiva I.: Western side, above Uea Valley, near Baie Marquisienne, 150–200 m, Decker 2046 (US, P, BISH) (leaves lance-elliptic, cymes full but loose); Tovi’i, Quayle 1338 (BISH).

Uahuka I.: s.l. Quayle 1753 (BISH), 1836 (BISH).

Hivaoa I.: “Hauts plateaux,” Henry in 1919 (P); Atuona-Feani trail, 1200–1300 m, Sachet & Decker 1174 (US, BISH, P); Feani, 900 m, Brown 879 (BISH, type); “route de Hana-menu,” 600 m, Henry in 1922 (P); north side of Mt. Teme-tiu, PES (A & M) 146 (UC, BISH as M&A) (a small leafed form); Atuona Valley, 1100 m, PES Ex 140 (BISH); Teihuonui, 3400 ft [1000–1200 m], PES (A & M) 498 (NY).

Alyxia Banks ex R. Brown

Alyxia Banks ex R. Brown, Prodr. 469, 1810 [nom. cons.].

Gynopogon J. R. & G. Forster, Char. Gen. 18, 1775; 35, t.18, 1776.

Twining vines or shrubs, leaves opposite or whorled, usually rather small, flowers in small axillary pedunculate cymes, corollas small, salverform, fruit a pair of subglobose carpels, each with a single stone or with two or more moniliformly arranged stones, the whole often reduced by abortion to one drupe or an end-to-end pair of drupes.

An important Indo-Pacific genus, centered in Malesia and New Caledonia, with at least one representative in almost every high island in Polynesia and Micronesia.

Alyxia stelfota (J. R. & G. Forster) Roemer & Schultes

Alyxia stellata (J. R. & G. Forster) Roemer & Schultes, Syst. Veg. 4:439, 1819.

Gynopogon stellatum J. R. & G. Forster, Char. Gen., 18, 1775; 36, 1776.—Forster f., Prodr. 19, 1786.

Alyxia stellata, described from the Society Islands and Tonga, extends in various forms from at least as far west as New Caledonia to the Marquesas and Henderson Island. It is supposedly distinguished from A. scandens (also from Polynesia but not known from the Marquesas) by ternate vs. opposite leaves, but these occur too often on the same plant. It seems to be more reliably distinguished from A. scandens by considerably smaller flowers.

F. Brown (1935:230–231) placed all Marquesan material in his f. marquesensis, while admitting its variability. Three varieties are now recognized from the Marquesas.

Alstonia costata, synonyms including Alstonia marquisensis, is a species of flowering plant in the family Apocynaceae, native to the Solomon Islands in Papuasia and to islands in the south Pacific. It was first described by Georg Forster in 1786 as Echites costatus. It grows as a shrub or tree.

Alstonia marquisensis est une espèce de plante de la famille des Apocynaceae. Elle est endémique de la Polynésie française.

Alstonia costata là một loài thực vật có hoa trong họ La bố ma. Loài này được (G.Forst.) R.Br. mô tả khoa học đầu tiên năm 1810.