ORCHIDS IN SOUTH KALIMANTAN TROPICAL FOREST

Descriptions of the major genera and species

Grammatophyllum is a small genus consisting of about six species confined to Malaysia and Indonesia. There are two types of growth-form in the genus. One has very long pseudobulbs which are really fleshy stems, bearing many leaves; the other has rather short proportionately thick pseudobulbs which are not covered by leaf-bases, with few leaves at apex. The flowers are similar. They are epiphytes with pseudobulbs in close groups, short or long with few or many leaves. Leaves 2-ranked, not thickened. Inflorescences erect or drooping, with many large flowers. Sepals and petals nearly alike. Lip with 3 low keels; pollinia 2. Grammatophyllum speciosum (Figure 2 and 18), usually called giant orchid was noted in four different localities: at Missim on a durian tree and Km 67, Km 81 and Km 74 high above the ground on old big trees. The stem is up to 3 m long, 5 cm thick, internodes about 4 cm long. Leaves thin, usually about 50-60 cm by 3 cm. Inflorescence to 2 m long with many flowers, the lower ones distant while the upper ones close flowers of about 10 cm wide, sepals and petals widely spreading, pale greenish yellow with large dull orange brown spots. Sepals to 5.5 by 2.5 cm; petals a little wider. Lip smaller, barely 3 cm long within hairy and striped with red

brown; side lobes erect, curving over the column, yellow with brown stripes. Distributed from Sumatera to the Philippines. In Penang they usually flower in July, in Singapore either July or December, and in Bogor usually December and January. Eria is a smaller genus than Dendrobium but still a very extensive one. As in Dendrobium, there is a great range of vegetative form, and it is possible to divide the genus into easily recognizable sections on vegetative characters. Formerly the genus Trichotosia has been merged into the genus Eria but nowadays it has been put in a separate genus again.

Each of the sympoda may short or long, slender or thick and fleshy, bearing one or more leaves, while the basal part is always covered with sheaths. Inflorescence may be lateral or terminal with one to many flowers. Flowers are usually small. Flower structure is the same as in Dendrobium but the base of the lip never form a spur by uniting with the edges of the column-foot. Pollinia 8, in two groups of four. During the collecting trip 23 Eria specimens were collected. Most of them have small flowers with pale color and not ranked as decorative plants, though some of them are attractive when in full flower. Inspite of its many species, none have been used for breeding purposes. E. javanica is said to be the most common Eria species in Indonesia. It has an erect ovoid pseudobulb 5 to 7 cm tall bearing two large foliage leaves. Leaves erect, fleshy to about 50 cm long, 6 cm wide. Inflorescence arising near the top of the pseudobulb to about 60 cm long with flowers almost to the base. Flowers face in all directions, about 4 cm wide, fragrant, white almost pale yellowish, often with purple veins. Distributed from Sumatera to the Philippines. This is one of the few Erias that are sometimes cultivated. Flowers are short-lived.

Eria multiflora is also widely distributed from Sumatera, Java, Peninsular Malaysia to Borneo. Stem up to 30 cm long, of even thickness, 1 cm or more diameter. Leaves elliptical, 4 to 6, thin, commonly about 20 by 2 cm. Inflorescence obliquely ascending from the upper part of the stem, about 12 cm long, bearing small, crowded flowers white with faint pink suffusion on the lip, some very dark red, margins of stigma dark purple. Height of the flowers 2.5 mm, width 1.5 mm.

Agrostophyllum is a genus of about 60 species, extending from Seychelles to the islands of the Pacific. It is one of the most common orchid genera of lowlands and mountains. Several species have very similar vegetative appearance but quite distinct flowers.

Stem is up to one metre long, usually with many internodes, often flattened. Leaves are in two ranks narrow, rather thin with overlapping sheaths. Inflorescence in terminal heads, usually of many flowers. Sepals and petals similar; lip sac-shaped at the base, the hollow divided from the blade by a transverse partition. Column short or relatively long. Pollinia 8, all attached to a single disc.

Two species are common in Indonesia, A. mayus and A. bicuspidatum. In the first one, stem is up to 100 cm long, flattened, widening towards the tip, internodes 2-4 cm long. Leaves many, the lowest small, upper larger, to about 18 by 1.7 cm narrowed slightly towards the tip. Inflorescence head, 2.5 to 3 cm in diameter formed on many short crowded branches. Flowers small, white, the edges of the column and the partition of the lip, purple-red. Lip in natural position 2.5 mm long and wide. A. bicuspidatum, stem up to 20-40 cm long, leaves at right angle to the stem, 0.5- 1.3 cm wide near the base, narrowed slightly to a rounded cleft tip. Inflorescence terminal, flowers white or pale yellow, upper sepal 3-4 mm long, 2 mm wide, erect, concave. Native to Sumatera, Peninsular Malaysia, Java and Borneo.

Among the terrestrial orchids found in the PTAYI forest are Bromheadia finlaysoniana and Eulophia squalida. Bromheadia is a small genus, extending from Sumatera to Papua New Guinea. Seven species occur in Peninsular Malaysia, but no species are found in Java which is very strange. The flowers are much alike in all species, differing in size and small details of colouring; most are pale yellowish with purple and yellow markings. The character which all Bromheadia share is the short life of their flowers which open in the morning and fade by noon.

Bromheadia finlaysoniana is commonly up to 1 m high, basal part with green sheaths. Leaves in two rows, 12 by 3 cm, wider near the base,fleshy. Inflorescence erect, sometimes branched, commonly 10 cm long, bearing flowers 1 or 2 at a time, at internal of about 10 days. Flowers white or cream, sometimes tinted with mauve, sepals 2.8 to 3.8 cm long 6-9 cm wide, acute. Petals a little shorter and wider. Lip 3.3 cm long, side lobes erect, veined with purple. Distributed in Sumatera, Peninsular Malaysia and Borneo. Eulophia is distributed through the tropics, especially in Africa and is seems that Eulophia is much better developed in Africa than in Asia. E. squalida has pseudobulb below ground, almost round, 3 cm in diameter, bearing 3 to 4 leaves. Leaves are stalked, grooved, 50 by 15 cm. Inflorescence to 100 cm long. Sepals 2 by 0.5 cm, acute, the laterals joined at base to the widen column-foot, dull brownish-olive. Petals overarching column with upcurved tips, 1.7 by 0.8 cm, pure white, or base greenish and red. Lip with broad flattened spur pointing downwards, pale mauve with white or cream central area, mauve and brown-veined. Distributed from Sumatera to Papua New Guinea and the Philippines.

Flickengeria was formerly ranked as a section in the genus Dendrobium which was later lifted into a genus which is now fully accepted. Rhizomes rooting along their length, creeping and usually branched, producing stems at intervals. Stems extending for a few nodes then terminating in amore or less thickened internode or pseudobulb. A single leaf is produced from the apex or every pseudobulb; at its base many potential flower buds of which at interval buds develop and one or two flowers are produced at a time. Flowers only last for a single day. Among them F. comata is worth mentioning as it is widely distributed in Indonesia. Stem yellowish, long and much branched. Leaves broad to about 10 by 5 cm. Flowers about 2.5 cm diameter, sepals and petals pale yellowish with pale purple spots. Mid lobe of lip bordered with long yellow hairs. The flowers are very fugacious.