Pinguicula panfetiae Panco, P. Temple & Y. Domínguez, 2025

Pančo, Ivan, Temple, Paul, Rodríguez Cobas, Geovanys, Coutin Lobaina, Noel, Matisova, Ivana & Domínguez, Yoannis, 2025, Pinguicula panfetiae (Lentibulariaceae), a new Caribbean butterwort from eastern Cuba, Plant Ecology and Evolution 158 (3), pp. 382-391 : 382-391

Pinguicula panfetiae Panco, P. Temple & Y. Domínguez sp. nov.

Figs 1 , 2 , 3 , 4 A

Type

CUBA – Guantánamo • Yateras, Parque Nacional Alejandro de Humboldt, Palenque, Cayo Fortuna, cuenca del río Toa, 3 km desde la estación Piedra La Vela ; 20°24’54.6”N, 74°57’39.5”W; 460 m; 31 Mar. 2023; J. Imbert Planche, I. Pančo, G. Rodríguez Cobas, I. Matisova, N. Coutin Lobaina s. n.; holotype: HAJB [ G 002601 ]; isotypes: B, BSC [22092] .

Diagnosis

Pinguicula jaraguana Casper affinis sed brevibus, foliis ovobatis, erectis suberectis, margine integerrima non involute, flores parvi 10–13 mm (calcari incluso), semina 0.6–0.7 mm longa (appendix incluso), 0.18–0.22 mm lata.

Description

Perennial herb, scapose, in a basal rosette, (19 –) 25–30 (– 35) mm in diameter; suberect to erect, sometimes growing densely grouped together in colonies of many individuals exhibiting calathiform rosettes. Rhizome short, with fibrous roots. Leaves (4 –) 5–7 (– 10), homophyllous, yellow-green or reddish-brown, (10 –) 12–15 (– 17) × (6 –) 8–10 (– 11) mm, obovate, apex rounded, base narrowly cuneate into a short petiole, margins entire; adaxial surface densely covered with glandular trichomes. Scapes 1 (– 3), 1 - flowered, erect, green or reddish-brown, (50 –) 80–110 (– 150) mm long, ± 0.30–0.45 mm thick, sparsely glandular with very few stalked and sessile trichomes. Flowers white, indistinctly 2 - lipped (subisolobate). Calyx distinctly 2 - lipped, similar colour to leaves, shorter than the tube, ± 4 mm; outer surface sparsely covered with stalked glandular trichomes; upper-lip divided nearly to the base into 3 lobes, lobes oblong-obtuse, apex retuse, ± 2 × 1 mm; lower lip 2 - lobed, the lobes free nearly from their bases. Corolla (8.5 –) 9–10 (– 11.3) mm long (including the spur), ± 9 mm diameter, widely opened; the lobes forming an angle with the tube of ± 90 °, broadly obovate, margins overlapping for less than half their length, white, (3.8 –) 4–4.7 (– 5.2) × (2.9 –) 3.5–3.8 (– 4.3) mm, adaxial surface covered sparsely with non-glandular trichomes that are more abundant at the entrance to the tube; upper lip 2 - lobed, lobes smaller than the two lateral lower-lip lobes; lower-lip deeply 3 - lobed, lobes obovate, apex rounded, midlobe (4.5 –) 4.8–5 (– 5.2) × (3.8 –) 4 (– 4.2) mm. Tube yellow with deep brown veins, cylindric, short, (2.5 –) 3–4 (– 4.5) × 1.5–2.5 mm, without palate, distinctly bent (geniculate) and held at an angle of ± 90 °, tripartite, the entrance with long uniseriate non-glandular trichomes, the middle part with medium-length uniseriate and stipitate glandular trichomes, the inner part with short glandular trichomes. Spur yellowish-brown, thick, conical, very short, (2.5 –) 3–4 (– 4.5) × 1.5–2.5 mm, apex rounded, saccate. Stamens ± 1.5 mm long, slightly curved; anthers ± 0.5 mm wide. Pollen prolate (P: E = 1.49), zonoaperturate, 4 (5) - colporate, (34.63 –) 35.52–37.32 (– 39.17) × (23.53 –) 24.12–24.88 (– 25.39) μm. Ovary subglobose-ovoid, sessile, ± 1.5 mm in diameter, 1 - loculate, ending in a short style, glabrous. Stigma short, 2 - lobed, margin fringed. Capsule globose, ± 2 × 2 mm. Seeds dark brown, fusiform, (440 –) 520–540 (– 590) × (180 –) 200–215 (– 220) μm excluding appendage, testa reticulate, mycropilar appendage prominent, (60 –) 80 (– 90) μm.

Etymology

Pinguicula panfetiae is named in honour of the late Cuban botanist, Prof. Dr Cristina Mercedes Panfet Valdés, to acknowledge her contributions to Cuban flora research, in particular, with regard to the carnivorous plant families for which she was the main Cuban specialist. Besides her research, Prof. Panfet dedicated most of her life to empowering many generations of Cuban botanists to achieve professional standing, which is also acknowledged herein.

Phenology

Based on the presence of flowers or fruits, or both, in the analysed specimens and according to the in situ observations, the flowering period extends from February to June.

Distribution and habitat

Pinguicula panfetiae is endemic to eastern Cuba (Fig. 3 ) where it is limited to a small area within Cayo Fortuna, a subdepartment of the Ojito de Agua sector of the Alejandro de Humboldt National Park. Plants are found at an altitude of ca 460 m, on steep slopes above the banks of the River Toa (Fig. 2 F ), where they grow in dense patches totalling a few thousand individuals. Where a group of plants grow in a tight arrangement, they typically exhibit calathiform (cup-like) rosettes with suberect to erect leaves (Fig. 2 H ). While we can be certain of the location of Pinguicula panfetiae in Cayo Fortuna, the records of the locations of other specimens mention Palenque, Cayo Fortuna, or eastern Cuba (Oriente) but the use of such names is not detailed enough to determine whether any corresponds to the true Cayo Fortuna or to one or more other locations. The vegetation at the type locality is semi-arid montane serpentine shrubwood (charrascal) that occurs in association with ferritic soils derived from serpentine bedrocks ( Borhidi 1996). However, Pinguicula panfetiae grows on permanently wet landslides and seeps on or just above rivers banks. Despite the semi-arid conditions of the charrascal, this area supports edaphic climax communities developed under a humid tropical rainforest climate.

Relationships

According to the infrageneric classification proposed by Fleischmann (2021), Pinguicula panfetiae belongs to subg. Temnoceras Barnhart, sect. Homophyllum Casper , which also includes all Caribbean species from Cuba and the Dominican Republic. Among the Cuban species, Pinguicula panfetiae shows close morphological affinities with P. albida and P. jaraguana as they have white flowers with subisolobate corolla and a thick, short spur. However, morphological and morphometric analyses have shown that these three species can be separated on the basis of vegetative and reproductive traits (Figs 4 , 5 ). In addition to the differences highlighted in the diagnosis, a comparative overview of Pinguicula panfetiae , P. albida , and P. jaraguana is provided in Table 2 .

Preliminary IUCN assessment

Very few records exist for this species according to the analysed material in herbarium collections and, due to the limited access to material and insufficient information associated with old specimens (1970–1972), it is difficult to determine if all of them originated from a single population. Casper (2019) remarked that several of the independent sightings of plants, herein described as Pinguicula panfetiae , may all represent records for the same and currently only known population (Fig. 3 ). Observations from our field explorations in eastern Cuba support Casper’s view. This population already has the highest Cuban protection status and comprises thousands of plants. Nevertheless, the population is restricted to small patches in a narrowly defined area; most occur on disturbed ground from recent landslides where they are at risk of further similar events. Therefore, based on the number of known locations (1), the extent of occurrence and the area of occupancy ( EOO / AOO = 0.810 km 2), the preliminary conservation status proposed is Critically Endangered CR B 1 ab (i, ii, iv) + B 2 ab (i, ii, iv) following IUCN criteria ( IUCN 2024).

Additional material studied ( paratypes)

CUBA – Oriente [ Guantánamo] • Palenque, Cuchillas de Toa, Cayo Fortuna, a lo largo del río Toa ; Apr. 1970; J. Bisse HFC- 16747; HAJB • Palenque, Cuchillas de Toa, Cayo Fortuna, a lo largo del río Toa ; Apr. 1970, J. Bisse HFC- 16918; HAJB • 35 km nordöstlich von Guantanamo, Gebiet von Palenque, Cayo Fortuna, Auf überrieseltem Felsen am Ufer des Rio Toa ; 22 Mar. 1972; F. Ebel s. n.; HAL [36587] .

Figures

Figure 1. Pinguicula panfetiae based on type specimens (holotype HAJB [G 002601], isotypes B, BSC [22092]) and on living material. A. Habit, perennial herb with details of the trichomes of the leaf and the inflorescence scape (circles). B. Emerging leaf with involute margin. C. Frontal view of the flower. D. Lateral view of the flower. E 1. Internal trichomes of the outer part of the corolla tube. E 2. Internal trichomes of the middle part of the corolla tube. E 3. Internal trichomes of the inner part of the corolla tube. F. Dissected flower with the persistent calyx and lateral view of the stamens and gynoecium. G. Fruit with persistent calyx. H. Lateral view of the seed. Illustration by Yoannis Domínguez.

Figure 2. Pinguicula panfetiae at the type locality in the Alejandro de Humboldt National Park, eastern Cuba. A. Habit. B. Frontal view of the flower. C. Lateral view of the flower. D. Dissected flower showing the persistent calyx and stamens and gynoecium. E. Lateral view of the fruit. F. Habitat at the banks of the River Toa. G. Regular rosettes with suberect leaves. H. Calathiform rosettes with erect leaves. Photos by Ivan Pančo (A – E, G – H) and Ivana Matisova (F).

Figure 3. Distribution of Pinguicula panfetiae, Pinguicula albida, and Pinguicula jaraguana in Cuba based on herbarium records and field surveys.

Figure 4. Distinct vegetative and reproductive morphological traits of related species. A. Pinguicula panfetiae. B. Pinguicula albida. C. Pinguicula jaraguana. Photos by Ivan Pančo (A, C) and Yoannis Domínguez (B).

Figure 5. Principal component analysis based on vegetative and reproductive quantitative traits of Pinguicula panfetiae, Pinguicula albida and Pinguicula jaraguana. A. Projection of the analysed variables onto the first two principal component axes (Factor 1 and 2). B. Projection of the sampled individuals for each species onto the first two principal component axes (Factor 1 and 2). Character codes correspond to those in Table 1.