Restrepia guttulata, commonly called the small-spotted restrepia, is a species of orchid occurring from Venezuela to Ecuador.
Introduction
Restrepia guttulata, commonly known as the small spotted restripia, is an epiphytic orchid in the family Orchidaceae. It is native to the South American Andes and Sierra Nevada de Santa Marta mountain ranges in Colombia, Ecuador, and Venezuela. It belongs to one of the largest subtribes in the orchid family, the Pleurothallidinae. As the common name suggests, the flowers of this orchid are ornamented with spots or specks. Flowers are multicoloured, ranging from white, pink, purple, yellow, orange, burgundy, and brown. There is circumstantial evidence to support that flies act as pollinators to Restrepia guttulata. Conservation of this orchid is crucial, as it is considered endangered or vulnerable in most of its range. It is thought to have been extirpated entirely from Venezuela, now being considered extinct in the wild there. This is due to habitat loss and fragmentation. This has also caused serious declines in R. guttulata’s ability to cross pollinate with other members of its species. Ex situ conservation, which is any conservation effort which harbours plant material away from its native habitat, is crucial for such endangered orchids as Restrepia guttulata.
Description
Like many orchids, Restrepia guttulata is a herbaceous, epiphytic plant, growing on other plant surfaces like branches and stems. Its vegetative body is small and grows in clusters or tufts. It grows to 30 cm in height and has erect rigid leaves that are leathery in appearance and texture. Leaves are elliptic or ovate in shape with a cuneate base and acute apex. Leaves generally grow to 6 by 3 cm and up to 8 by 3 cm. The leaf margin, or edge, is sharp. The midvein is recessed into the leaf blade, creating a conspicuous channel down the centre of the leaf. This causes the leaf to resemble the bottom of a boat, and is thus termed a keeled leaf. The stems are 11 cm in length and covered in white papery sheaths ornamented in dark brown spots near the base.
R. guttulata’s flowers grow solitarily and successively upon a thin, light green, up to 7 cm peduncle. The leaves are twisted such that flowers emerge and are positioned behind the leaf. Flowers consist of a purple ovary, a free dorsal sepal, translucent petals, an oblong lip, fused sepals, a column, and male and female reproductive organs. Sepals are membranous and translucent to white, purple, pink, or yellow and ornamented with purple to pink markings and a purple to brown or yellow midvein. The dorsal sepal is 24 by 3mm in size and has a fleshy pink apex. The lateral sepals are almost entirely fused, with a small part near the tip. This fused lamina is 23 by 10mm in size. The lamina’s apex is truncate or retuse due to the splitting of the sepals. It is green to yellow, pink, and/or light orange/brown in colour. It is ornamented with purple, pink, and/or burgundy spots or specks. Spots begin heavy and round at the base of the lip and gradually become finer near the apex. Petals are membranous and translucent with purple veins along the entire length, from the apex to the base. They are 13 by 1mm in size with minutely serrated margins. The coloration of the petals is the same as the dorsal sepal, and also shares the characteristic of having a fleshy apex. The lip is up to 10mm in length with a light brown coloration and patterned in pink spots. The column is off-white to cream coloured and has a burgundy coloured portion near the base on the underside. The anther is cream coloured and the four pollinia attached to it are yellow and hard.
R. guttulata has been observed flowering in January, March, May, August, and December. Upon flowering, the individuals of the species require pollen from another individual to achieve successful pollination and seed production. This reproductive strategy, known as self-incompatibility, was confirmed to be a shared characteristic in the genus Restrepia by a 2015 study. Pollination is thought to occur with the help of flies. The subtribe Pleurothallidinae in which R. guttulata is situated has been described as a fly pollinated group as a whole and some studies have shown evidence of pollination in Restrepia. This evidence includes the presence of appendages called osmophores which help to guide the fly into the flower as well as the production of fly attracting aminoid fragrances.