An orchid with matchsticks

Pteroceras longicalcareum is an epiphytic orchid that is endemic and widespread in the Philippines, having been found on Bataan, Bulacan, Camarines (exact province not known), Laguna, Mountain Province, Nueva Vizcaya, Quezon and Sorsogon on Luzon; the islands of Polillo and Mindoro; Leyte in the Visayas; Agusan (no records exist as to the exact province) and Davao del Sur (Sta. Cruz) on Mindanao; and Balut Island off Sarangani. The plants are epiphytic on tree trunks and (mostly horizontal) branches in mixed dipterocarp forests, riverine forests and mangrove forests. Host trees are commonly Ficus and Vitex, though certainly are not restricted to them. Altitudinal distribution is from sea level to 1030 m. The specific epithet came from the Latin longi- long, and calcar spur, an obvious reference to the long nectary of this species, which have a curious resemblance to matchsticks. Compared to many other orchid species with elongated nectaries, those on this species, as well as on related taxa, are positioned in front and give the flowers a curious aspect.

This orchid has pendulous to upwardly curved, unbranched stems to around 50 cm. long with prominent, rampant roots almost concealing its entire length. The leathery and strap-like leaves are broadly lanceolate to oblong-elliptic. The pendulous inflorescences lengthen progressively up to 1 m. in length and produce batches of flowers several times a year.

Flowers are from 9 mm to 1.4 cm. across and fragrant. These blooms open up early in the morning and last up to 6 pm on the same day they open. Flowering is variable across its range, but has been observed during the months of January, March to July and September to November.

Photo below depicts the elongated roots that are produced from along the stem length. To maintain the health of these plants, such roots have to be watered or misted frequently particularly during the drier months. Failure to do so can lead to progressive desiccation.

This is a very showy species when in flower, though seldom seen in collections. They prefer lowland to intermediate climates with filtered light; in more humid areas they can withstand some noontime sun, though foliage turns an unattractive yellow. Grow them on mounts or baskets to accommodate the pendulous stems and inflorescences, and water throughout the year.

Quite interestingly, the flowers are pollinated by butterflies, with the white, mound-like callus serving as a landing pad. To reach the nectar reward kept at the dark, violet-brown, bulbous tips, a butterfly has to reach deeply, which forces it to extend its head underneath the column and results in the pollinia being dislodged and deposited on the butterfly's head. Only butterflies of the right size can manage to obtain the sweet reward. The inflorescences are the longest known in any species within the genus.