Paphiopedilum Pfitzer

The range of Paphiopedilum extends from India eastward across southern China to the Philippines and throughout south-east Asia and the Malay Archipelago to New Guinea and the Solomon Islands. Of the seven Indian species, six are confined to the north-east, along the foothills of the Himalaya from eastern Nepal to the Naga Hills, and also in the Khasia Hills. One species, P. druryi, is found only in southern India, in Kerala State, over 2000 km from the nearest Paphiopedilum locality to the north.

Five species of Paphiopedilum have been reported as growing epiphytically. Paphiopedilum parishii, P. lowii, and P. villosum are usually found growing on trees, whereas P. hirsutissimum and P. glanduliferum are facultative epiphytes. The remaining species are either terrestrial or lithophytic.

Most of the species are to be found growing in small colonies with their roots in leaf litter, often spreading some distance from the base of the plant. In some species of subgenus Brachypetalum (P. concolor, P. bellatulum, P. niveum) and in subgenus Paphiopedilum sects. Corypedilum (P. stonei, P. sanderianum, P. philippinense), Pardalopetalum (P. dianthum) and Paphiopedilum (P. hirsutissimum var. esquirolei, P. barbigerum), for example, the plants will grow with their roots attached to a rocky substrate and are true lithophytes.

Small to large terrestrial, lithophytic or epiphytic herbs; roots elongate, fibrous; rhizome short to elongate. Shoots short, erect, leafy, clustered or less frequently well spaced, glabrous, the base enclosed by two to four sheathing sterile bracts, three- to several-leaved above. Leaves one to several, coriaceous, conduplicate, spreading or suberect, ligulate, elliptic, or oblong, obtuse to acute, often tridenticulate at apex, green, bluish green, or chequered or tessellated with dark and lighter green on upper surface, lighter green below, sometimes finely spotted or flushed with purple at base or all over, glabrous, ciliate or not on the margins. Inflorescence terminal, one- to many-flowered; rachis terete, hairy, glandular or glabrous; bracts conduplicate, elliptic, lanceolate, ovate or oblong, green, sometimes spotted or flushed or striped with purple, ciliate or not. Flowers usually showy, concolorous or bicoloured; pedicel obscure to short; ovary unilocular, three-ribbed, glabrous or hairy. Dorsal sepal erect to hooded over lip, ovate, lanceolate, obovate or elliptic, obtuse, acute or acuminate, glabrous or pubescent on the outer surface, sometimes pubescent within at base, ciliate or not. Lateral sepals usually fused to form a concave synsepal that is more or less similar to the dorsal sepal, sometimes keeled on outer surface. Petals free, spreading or pendent, flat, reflexed or spiralling, elliptic, ovate, lanceolate, linear-lanceolate, linear or oblanceolate, rounded, obtuse, acute or acuminate at apex, often pubescent in basal half within, usually ciliate. Lip deeply pouched and inflated, slipper-shaped or urn-shaped, with more or less pronounced incurved side lobes, hairy within especially on lower surface, glabrous or hairy on outer surface; front margin incurved or not. Column short, stalked, porrect; anthers two, bilocular, borne on short obtuse to acute filaments; pollen powdery or viscid; staminode terminal on column, sessile or shortly stalked, transversely reniform, oblong, ovate, obcordate or linear, flat, convex or longitudinally conduplicate, glabrous to papillose or finely pubescent, ciliate or not; stigma stalked, dependent, tripartite, more or less papillose. Capsule erect to pendent, three-ribbed, cylindrical to almost ellipsoidal. (PC).

Species of Paphiopedilum are found from India east across south-east Asia to the Philippines in the west and from southern China in the north, south to the Malay Archipelago, New Guinea and the Solomon Islands. Several species are found at sea level, for example P. philippinense and P. glanduliferum, but the majority are found in hill country, sub-montane and montane conditions. In the Himalayas, P. fairrieanum grows at elevations up to 2200 m, and P. villosum up to 2000 m; likewise in western Yunnan in China, both P. tiginum and P. armeniacum have also been reported from 2000 m. In Borneo P. hookerae var. volonteanum has been found at 2300 m elevation on the slopes of Mt Kinabalu.

The genus is found over an elevational range from, sea-level to about 2300 m, but only in P. hookerae, P. bullenianum, and P. lowii has a species been found over a wide elevational range, the first of these with the most extensive range. Paphiopedilum hookerae var. volonteanum, in Sabah, grows on ridges in lower montane forest at 900 m and again on Mt Kinabalu on a landslide at c. 2300 m elevation. On Mt Kinabalu P. lowii, usually a lowland species, has been recorded from c. 1600m.

The majority of Paphiopedilum species grow in lower montane evergreen or seasonally deciduous forest, often on the forest floor in shade. A few species such as P. exul and P. philippinense have been recorded as growing in exposed sunny places. More commonly, though, species such as P. niveum, P. philippinense and P. rothschildianum, which will grow in more open positions, are seldom exposed to direct sunlight for any length of time during the day. On Mt Kinabalu in Sabah, P. rothschildianum grows where dappled sunlight hits the plants only in the afternoon. In contrast some of the tessellated-leaved species grow in deep shade. In Java and Borneo, P. javanicum and its var. virens grow on the forest floor in places where no direct sunlight penetrates.

In many areas where Paphiopedilums grow, the rainfall and consequent humidity are high, but rainfall is usually seasonal, and plants in such areas often have to survive considerable dry periods. The thick coriaceous leaves are ideally adapted to survive periodic droughts, and plants recover rapidly when the rains return. Most growers who have received plants through the post will support the view that Paphiopedilums can survive well in such adverse conditions. (PC).