Tajinaste azul genciano
A plant belonging to the borage family (Boraginaceae), it was described by the English botanist Philip Barker Webb based on herbarium material collected in 1845 by the French botanist Eugène Bourgeau in the highlands of Garafía, on the Canary Island of La Palma.
Distribution
This species is endemic to the island of La Palma, growing in the high peaks of the Caldera de Taburiente National Park, mainly in the northern half of the caldera and its surrounding ravines.
Habitat
It naturally occurs at altitudes between 1,800 and 2,400 meters, typically found on hillsides, rocky outcrops, and scree slopes around the edge of the Caldera de Taburiente. However, it can rapidly colonize lower areas of shrubland and pine forest, and appears spontaneously after wildfires or in areas where landslides and rockfalls have created clearings. At lower elevations, it is cultivated in private gardens. Flowering occurs between June and July, depending on whether the orientation is north- or south-facing, and fruiting happens within about a month.
Conservation
The currently known populations consist of about 5,000 reproductive adult plants, a significant increase from the roughly 50 individuals known in 1986. This sharp increase appears to be linked to the near disappearance of grazing in the last 40 years, along with conservation efforts by the National Park, including seed collection and subsequent reintroduction and reinforcement of populations through sowing. The main threats to this species are browsing by mammals such as goats, rabbits, and Barbary sheep (Ammotragus lervia). The Caldera de Taburiente National Park has included this species in its monitoring network as part of Spain’s PIMA Plan for Adaptation to Climate Change.
Image description
The seeds of this species, known as nutlets, are found inside the flower’s calyx in groups of four. In the optical microscope image, we can see these nutlets, which have a tetrahedral pyramid shape, with the apex elongated into a pointed tip and lateral ribs lined with small spines. Between the ribs, the surface displays a sinuous ornamentation in light brown over a dark brown background, also featuring spines.
The scanning electron microscope image shows a high-resolution detail of one of the spines, which appears curiously rounded.