Pinguicula elongata — Vorstman's Guide to the Carnivorous Plants

Identification

The plant has two kinds of leaf, and that difference is the whole story. The lower leaves are broadly ovate to obovate, six to twelve millimetres long and five to nine wide: an ordinary small butterwort rosette. Above them, in the growing season, appear linear-lanceolate leaves one hundred and five to one hundred and fifty millimetres long and only five to ten millimetres wide, held erect or hanging slack. Both types are covered in glands and sticky. The flower is violet with blue veins and, including the spur, fifteen to twenty millimetres long; the spur itself is short, thick and broadly conical, pale green, two to three millimetres. The combination of a long ribbon leaf and a flower with a thick, blunt, almost absent spur is unique in the genus.

Similar species

Once the long leaves are out, confusion with any other species in the area is hardly possible. Without them — early in the season or in young plants — the rosette resembles that of Pinguicula calyptrata, which occurs in the same páramo belt. The flower then helps: P. calyptrata has a slimmer, more pointed spur and a flower of at most fifteen millimetres, P. elongata a thick, broadly conical, pale green spur. The European species with comparably long leaves, P. vallisneriifolia, grows on another continent and on limestone, so that confusion remains theoretical.

The trap and how it works

A flypaper trap of unusual shape. The long narrow leaves offer far more sticky surface per plant than a flat rosette, and they stand not on the ground but among the tussocks, where flying insects shelter from the wind. The leaf carries the usual stalked glands with their droplet and the sessile glands that release enzymes only when prey is lying there. On a catch the narrow blade rolls inwards at the edges so that the digestive fluid stays in a groove — with this leaf shape almost automatic. The catch is small flies and midges; in the cold páramo digestion is slow and a prey item stays visible for days.

Habitat and ecology

Open páramo at about three thousand two hundred metres, above the treeline (R5), on wet, short-turfed ground and along boggy patches and springs between the tussocks (W6). It is a harsh setting: the wind blows all day, the temperature falls to around freezing almost every night of the year, and only low plants and grasses endure. The soil is acid, cold and poor; organic matter breaks down so slowly that available nitrogen stays scarce. That is why carnivory pays at exactly these elevations.

Distribution and elevation

The species is known from the Colombian Andes, where it grows in the páramo of the eastern and central cordilleras; older records from Venezuela are poorly substantiated. It is therefore almost certainly endemic to Colombia. Its altitudinal range is narrow: around three thousand to three thousand four hundred metres, entirely within the páramo belt. As with all páramo species the range is in reality an archipelago — every ridge an island, separated by lower, forested valleys where the plant cannot grow.

Recorded (one-degree cells)

Distribution based solely on records at GBIF (Global Biodiversity Information Facility), not on TDWG regions — those are often far larger than the actual range. The light halo is the area around a record, the dark core the record itself. The darker cells are 12 one-degree squares — roughly a hundred and ten kilometres — in which the species has been recorded, from all GBIF records. This is coarser than for most species because hardly any record of this plant carries an accurate coordinate: the locality of poached species is obscured at source. At this scale that obscuring disappears into the noise. The cells show where it has been seen, not where it occurs: an empty square means nothing.

Forms and variation

No wild varieties are recognised. The most striking variation within the species is that between the two leaf types of the same plant, and it is seasonal rather than inherited: at the start of the growing season there are only short rosette leaves, the long ones come later. Anyone finding a plant without long leaves has caught a different moment, not a different form. Between populations it is mainly the intensity of flower colour that varies. No natural hybrids have been described; the only other butterwort in the area, P. calyptrata, usually does not stand right beside it.

Where and when to see it

In the Colombian páramo, sit down at the wet places and look between the tussocks rather than at them. The long leaves are green, limp and narrow and look exactly like grass until the light catches the glandular droplets; raking light early in the morning or late in the afternoon is therefore the best moment. Watch the sheltered sides of spring-fed rills and the boggy edges of small mires. The páramo is fragile: stay on firm ground and avoid trampling seepages, because that is precisely where the plant grows.

Conservation status

The species has not been assessed for the global IUCN Red List and is not in CITES, so there is no international category. What is known amounts to scattered herbarium records and a few field observations: no counts, no trend. It is clear, though, that the habitat as a whole is under pressure. The Colombian páramo is shrinking as stock and potato cultivation push upwards, through burning, and because a warming climate lifts the fog belt while there is no ground left above the summits. For a species with a narrow altitudinal band that last point weighs heaviest. The absence of an assessment here mainly reflects a lack of data.

Scientific name

Pinguicula elongata | Benjamin, 1847

Described by Ludolph Benjamin in 1847, in Linnaea 20: 318. The type area lies in Colombia, in a páramo environment at around 3200 metres elevation. The species name elongata is Latin for "elongated" and refers to this species' drawn-out, linear-lanceolate leaves.

World Checklist of Vascular Plants (WCVP), via Plants of the World Online (POWO), Royal Botanic Gardens, Kew.