ADDITIONS TO “RUBIACEAE OF THAILAND. A PICTORIAL GUIDE TO INDIGENOUS AND CULTIVATED GENERA”
misleading as the two genera have little in common. The most striking differences in the fertile parts concern both flower and fruit structure: While all Gardenia are characterized by flowers exhibiting secondary pollen presentation (SPP; see Puff et al. 2005: 32 & plate 2.4.1A for details), free anthers and at least partially exserted stigmas, Gardeniopsis lacks SPP and has stamens (with anthers forming a cone-like structure) and stigmas included in the corolla tube (Fig. 2E). Another very peculiar floral character is that its contorted corolla lobes never open and expand but rather form a kind of hollow sphere (Fig. 2C–D). The pollination mode of these flowers is unknown but it is presumed that small insects might enter the closed flowers via the lateral gaps formed by the contorted and twisted but not tightly adhering corolla lobes (see Fig. 2C). Yet another fundamental difference is the presence of a 2-celled ovary with a solitary ovule in each locule [ovary 1-celled, with numerous ovules on 2-9 parietal placentas in Gardenias]. Consequently, also the fruits (only 2-seeded in Gardeniopsis, vs. many-seeded in Gardenia) are strikingly different. Inflorescences of Gardeniopsis are axillary, those of Gardenia terminal. Vegetatively, Gardenias are usually easily distinguishable by having resin-coated buds, shoot tips and young parts (because of copious exudate production of colleters on the inside of stipules); this also is absent in Gardeniopsis.
To date, Gardeniopsis’ tribal affinities have not yet been satisfactorily resolved.
Hyptianthera Wight &Arn., Prodr. Fl. Ind. Orient.: 399. 1834.
Shrubs or small trees, evergreen, glabrous. Leaves opposite, shortly petiolate; stipules interpetiolar, deltoid-lanceolate. Inflorescences axillary, paired, sessile, much congested cymes; individual flowers subtended by a pair of bracteoles. Flowers sessile, 4- 5-merous, hermaphrodite. Calyx with a short basal tubular part and lanceolate lobes. Corolla hypocrateriform, tube about as long as the lobes, the latter contorted to the left in bud; glabrous on the outside, the inside with short hairs on the lobes and below the anthers. Stamens subsessile, inserted at or just below the throat; anthers basally hairy, almost completely included. Ovary 2-celled, each locule with several ovules pendulous from the apical part of the septum, crowned by a ring-like disk; style with 2 stigma lobes, the latter and the upper part of the style hairy. Fruit a drupe with a thin endocarp, 2-celled, each cell with usually up to 4–5 seeds.
A monotypic genus belonging to tribe Octotropideae (syn. Hypobathreae) and occurring from Nepal and E. India to China (Yunnan) and Indochina.—See notes below.
Hyptianthera stricta (Roxb. ex Schult.) Wight & Arn., Prodr. Fl. Ind. Orient.: 399. 1834; Hook. f., Fl. Br. India 3: 121. 1880 (pro parte); Pit. in H.Lecomte, Fl. Indo-Chine 3: 266. 1923; Craib in Fl. Siam. 2: 127. 1932.— Macrocnemum strictum Roxb. ex Schult. in J.J.Roemer & J.A.Schultes, Syst. Veg. 5: 6. 1819.— Rondeletia stricta (Roxb. ex Schult.) Roth, Nov. Pl. Sp.: 140. 1821.— Solena stricta (Roxb. ex Schult.) D.Dietr., Syn. Pl. 1: 800. 1839.— Hypobathrum strictum (Roxb. ex Schult.) Kurz, Forest Fl. Burma 2: 50. 1877.— Randia stricta (Roxb. ex Schult.) Roxb., Fl. Ind. 2: 145. 1924.— Hyptianthera bracteata Craib, Bull. Misc. Inform. Kew 1911: 393. 1911; Pit. in H.Lecomte, Fl. Indo-Chine 3: 266. 1923; Craib in Fl. Siam. 2: 127. 1932. Fig. 3.