Pinguicula mundi — Vorstman's Guide to the Carnivorous Plants

Identification

A rosette of six to twelve, sometimes fifteen leaves held obliquely or erect rather than lying flat. The spring leaves are three to six centimetres long, the summer leaves six to eleven centimetres and up to three centimetres wide — the plant changes shape with the season. The leaf is yellow-green, greasy and glistening with glandular droplets. The scapes are five to twelve centimetres tall, each with one violet flower whose corolla is fourteen to twenty-one millimetres, paler-marked in the throat. The spur is conspicuous: nine to fourteen millimetres, cylindrical and tapering to a point, directed almost horizontally backwards or slightly down.

Similar species

The nearest relatives are the other Iberian rock butterworts. Pinguicula vallisneriifolia of the Baetic ranges is larger still and produces long stolons with which it clothes entire faces; that character is absent here. Pinguicula casperiana, segregated in 2020, grows in the Serranía de Cuenca and was previously counted there under the name P. mundi — anyone reading older literature on that area should allow for it. Pinguicula dertosensis of the Ports lies further east. In practice the locality is the most usable character here.

The trap and how it works

A flypaper trap that works excellently in a permanently humid, shaded gorge. The leaf bears stalked glands with a clear adhesive droplet and, between them, sessile glands delivering digestive enzymes once prey is lying on them. In this habitat the supply consists of mosquitoes, midges, gnats and springtails living in the humid air along the water. After a catch the leaf margin rolls further inward, which on a sloping or overhanging face is the difference between digesting and losing the fluid. The tufa the plant sits on is all but worthless as a rooting medium, and that is exactly why carnivory pays here.

Habitat and ecology

Dripping, north-facing limestone walls and tufa deposits over which spring water runs permanently, in shaded gorges and at the foot of rock bands. The plant roots in crevices and in the porous, constantly wet tufa, generally out of direct sun. Drying out is not tolerated: where the spring fails in a dry year, the population goes. Elevation runs from about nine hundred to sixteen hundred metres. Such sites are rare and small in the Spanish limestone uplands, and they often hold a whole suite of moisture-loving species absent from the surrounding dry sierra.

Distribution and elevation

The central Iberian limestone uplands: the Serranía de Cuenca, the Sierra de Alcaraz and the Calar del Mundo, across the provinces of Cuenca, Guadalajara and Albacete. The specific epithet refers to the Río Mundo, whose source in the Calar del Mundo is one of the best-known sites. Since the segregation of P. casperiana in 2020 the centre of gravity of P. mundi has shifted to the southern half of this area; our own species list records only 'Spain', which is too coarse for a plant with so fragmented a distribution.

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 4 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 feature is seasonal dimorphism: the same plant carries short broad leaves in spring and considerably longer ones in summer, and anyone unfamiliar with both stages may take them for different plants. Corolla size also varies between twelve and twenty-three millimetres and spur length between eight and fifteen; plants on the wettest, most shaded faces sit at the upper end. The taxonomic circumscription of the species has been tightened twice in recent years, and that process is probably not finished.

Where and when to see it

May and June, when winter melt and rain are still seeping through the limestone and the walls are dripping everywhere. Search the north-facing, shaded gorges rather than the open sierra; follow a stream upward to where it leaves the rock. Look up: the rosettes often hang above the path against the wet face, and the violet flowers on their stalks show well against dark wet stone. Do not walk on the tufa lip at the foot of the wall — it is soft, breaks easily and does not recover within a human lifetime.

Conservation status

The species counts as of least concern. For a plant confined to a few dozen wet limestone faces that is a fairly favourable outcome, and it rests largely on the core of the range lying in inaccessible, protected uplands. The vulnerability remains: every site depends on a single spring flow, and the tapping of springs for drinking water and irrigation, falling water tables in long droughts, and road and water works driven through the gorges are real threats. Trampling around popular spring sites plays a part in a few places. CITES does not apply.

Scientific name

Pinguicula mundi | Blanca, Jamilena, Ruíz Rejón & Zamora, 1996

Described by Gabriel Blanca, Manuel Jamilena, Manuel Ruíz Rejón and Regino Zamora in 1996, in Plant Systematics and Evolution 200: 58. Until then the population had been mistakenly identified as Pinguicula vallisneriifolia, despite striking morphological differences. The type locality lies in the Sierra de Alcaraz, in the canyon of the Mundo river, in Albacete province, Spain, on limestone cliffs between 1000 and 1250 metres altitude. The name refers to the type locality: the Mundo river (Rio Mundo).

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