Rock Geniostoma

Shrubs or small trees, to 6 m tall. Branchlets glabrous or when young shortly brown to tawny tomentose. Petiole 1 cm; leaf blade narrowly ovate to narrowly elliptic, 7--16 X 3.5--6 cm, papery to subleathery, abaxially glabrous or sparsely hairy along midvein, base rounded to narrowly cuneate, apex obtuse, acute, or acuminate, lateral veins 6--10 pairs. Cymes sometimes partly on old branches, 3--18-flowered, often congested, rarely laxly paniculate or umbelliform, ca. 1 cm, glabrous or with sparse short appressed hairs; peduncle ca. 5 mm; bracts ovate to triangular, 0.5--1 mm. Pedicel 3--5 mm. Sepals ovate to triangular, ca. 2 mm, outside glabrous to densely short tomentose. Corolla campanulate, 2--5 mm, outside glabrous or rarely papillose-hairy, inside pubescent at mouth and sometimes with a second ring of hairs near base of tube; lobes ovate, 1.5--1.8 X 1.5--1.8 mm. Anthers narrowly ovate. Ovary ovoid, 0.4--1 mm, glabrous to densely short tomentose. Style and stigma glabrous or slightly pubescent. Capsules globose, 5--10 mm in diam. Fl. May-Jun, fr. Aug-Oct.

Taiwan (Lan Yu, Lü Dao) [Indonesia, Malaysia, Philippines; Australia, W Pacific Islands].

Thickets, along forest edges; ca. 300 m.

Geniostoma kasyotense Kanehira & Sasaki.

Geniostoma rupestre J. R. & G. Forster

Geniostoma rupestris [sic] J. R. & G. Forster, Char. Gen. 24, t.12. 1776.—G. Forster, Prod. 17. 1786b.—Sprengel, Syst. Veg. 1:588. 1825.—de Candolle and de Candolle, Prod. 9:26. 1845.—Bentham, Journ. Linn. Soc. Bot. 1:69, 97. 1857.—Gray, Proc. Am. Acad. 4:321. 1860b.—Pancher in Cuzent. Iles Soc. Tahiti 235. 1860.—Seemann, Fl. Vit. 163. 1866.—Nadeaud, Pl. Us. Tahiti. 36. 1864; Enum. Pl. Tahiti. 55. 1873; Journ. de Bot. 11:112. 1897.—Lanessan, Pl. Ut. Col. Franc. 863. 1886.—Butteaud, FI. Tahiti. 60. 1891.—Drake del Castillo, Ill. Fl. Ins. Pac. 7:236. 1892; Fl. Polyn. Franc. 126. 1892.—Hemsley, Journ. Linn. Soc. Bot. 30:185. 1894.—Burkill, Journ. Linn. Soc. Bot. 35:47. 1901.—Cheeseman, Trans. Linn. Soc. 6:288. 1903.—Gibbs, Journ. Linn. Soc. Bot. 39:157. 1909.—Rechinger, Denks. Akad. Wien 85:328. 1910.—Gilg and Benedict, Bot. Jahrb. 56:542. 1921.—Guillaumin, Bull. Soc. Bot. France 75:292. 1928.—F.B.H. Brown, Bish. Mus. Bull. 130:227. 1935 [non Reinecke, 1898; nec Valeton, 1902 (= G. gracilis Rechinger)].

Geniostoma crassifolium var. glaberrimum Bentham, Journ. Linn. Soc. Bot. 1:96. 1857.—Hemsley, Journ. Linn. Soc. Bot. 30:185. 1894.

Geniostoma aff. rupestris Christophersen, Bish. Mus. Bull. 128:176. 1935.

DESCRIPTION.—The following description of Forster's type in the Berlin Herbarium is compiled from Forster, Sprengel, de Candolle, and Gilg and Benedict. Glabrous. Branches subangled. Stipules broadly ovate, truncate above. Petioles of mature leaves 6 mm long. Blades lanceolate or ovate-lanceolate, asymmetrical, 4.5–6 × 2 cm, cuneate at base, blunt acuminate. Cymes axillary, subverticillate, 7–8 mm long, rather many-flowered. Pedicels bibracteolate at the middle. Calyx turbinate; lobes ovate, short, acute, ciliolate, persistent. Corolla tube 1.5 mm long, longer than the calyx, pilose at the throat; lobes ovate, 1.5 mm long, acute (Forster), blunt (Gilg and Benedict), spreading, heavily papillate within. Filaments short, hairy, anthers oblong, glabrous, with a conspicuous appendage. Ovary ovate, thick, almost glabrous; style filiform, 0.5 mm long, hairy; stigma capitate, obtuse, sulcate, hairy. Capsule oblong; seeds subangled.

Measurements made on Forster's plate indicate that the flowers are about 7 mm long and the capsule 8 × 3.5 mm. Gray however, has pointed out some of the discrepancies in the plate and the flowers are undoubtedly smaller, Gilg and Benedict giving the measurements above. Guillaumin, who is probably most familiar with the flora of the New Hebrides, from whence Forster's type comes, described the pedicels and flowers as each under 4 mm long. Grant saw a single collection of the species from this island group (Kajewski 728, Aneityum, det. Guillaumin). He had also seen 31 collections of Geniostoma from Fiji, all of which had been referred to G. rupestre by Gillespie (1932), the late expert on the Fiji flora, though Gilg and Benedict (1921:542) describe the Fiji plant as a new species, G. vitiense. The flowers are about 3 mm long, and in this large amount of material the capsules range from 5.5 to 13 mm long. It is unnecessary to state that the whole group needs further study.

Geniostoma gracile Rechinger (1909:325, Gilg and Benedict, 1921:544, Christophersen, 1935:175) of Samoa, appears to differ in rounded leaf base, longer corolla (4 mm), fewer (3–5) flowered cymes, longer (10–14 mm) pedicels and broader (5–6 mm) capsules. As to one of these differences, Reinecke (1898:666) states in regard to his collections (1 of which is referred to G. gracile by Gilg and Benedict) that the leaves are exceptionally narrowed at the base. Christophersen says the leaves vary from rounded to cuneate at base, and that the species is characterized by few-flowered cymes and slender pedicels. The type (Rechinger 1475, of which Grant saw a photograph) has the cymes mostly 5–flowered.

We have seen no material of the Tahitian plant, and no recent collector seems to have found it. Pancher apparently was the first to report this species from Tahiti, with the single remark “indigène.” As far as the native flora is concerned Pancher's paper was merely a compilation of previous lists, his only real additions being of cultivated plants. Possibly this citation is an error: he similarly records other Forsterian species (i.e., Melicytus ramiflorus) that are otherwise unknown from Tahiti. The first definite citation is that of Seemann (1866) “Tahiti (Cook),” and it was subsequently recorded by Nadeaud (1873:55) and Drake del Castillo (1892:126), the latter citing three specimens from Tahiti, including Nadeaud's, all collected before 1860. Drake del Castillo, having seen three of these four specimens, states that the leaves are 10 × 5 cm, the cymes 3–4 cm long, few-flowered, the style short, and the capsule 1 cm long. He also says “fleurs 1–2 mm,” which, if true, certainly cannot apply to this species. Nadeaud describes it as an “arbrisseau,” while all other reports from Tahiti and elsewhere call it a small or medium-sized tree.

The only Marquesan specimen known (Brown 1096, cited by Brown as no. 1996) has elliptical leaves, 6–7.5 × 2.8–4 cm, which are bluntly acute or barely acuminate. The flowers are immature.

The Rapan specimen (Stokes 384, also cited by F.B.H. Brown) has elliptical leaves, 6–8.5 × 3–4 cm, acute or slightly acuminate, with cymes 2 cm long and broad, flowers 3.5 mm long, “greenish-white, odor sickening” (Stokes' field label), the calyx lobes ovate, 1 × 1 mm, the corolla villous within, the ovary globose, 1 × 1 mm, style 0.5 mm long, and the stigma capitate, globose, 0.5 mm long, papillose. It appears to agree with Forster's type. Another very distinct species, G. rapense Brown, of which Grant saw the type, occurs on this island.

TYPE.—Collected by Forster in Tanna, New Hebrides in 1774.

RANGE.—Society Islands: Tahiti: Cook (BM, fide Seemann); Vesco in 1847 (P, fide Drake del Castillo); Lépine 208, Tautira, 1847 (P, fide Drake del Castillo); Nadeaud 363, mountain sides, 1856–1859, flowers in Oct., Dec. (fide Nadeaud) (P, fide Drake del Castillo).

There are many collections from New Caledonia, and the species has often been treated to include G. arboreum (Reinwardt ex Blume) 0. Kuntze of Java. See the remarks above on some of the material from Fiji, Samoa, the Marquesas, and Rapa. The species has also been recorded from Tonga (5 collections), Uvea, and, with a question mark, from Rarotonga (Cheeseman).

ETHNOBOTANY.—Tahitian: faipuu (faipun, Lanes-san (1886:863), typographic error) and atoro according to Nadeaud. Rapan: angae, fide F.B.H. Brown. Samoan: tai tai ipu, listed by Christo-phersen. Names in other dialects are recorded for the closely related species listed above.

According to Nadeaud, the leaves furnish a coumarin-like principle which the natives used in cosmetics. Brown states a medicinal extract is made from the bark in Rapa.

Geniostoma confertiflorum is a species of plant in the Loganiaceae family endemic to Fiji.