Paepalanthus versatilis Sauthier

Sauthier, Luana J., Tissot-Squalli, Mara L., Ramos, Renato & Sano, Paulo T., 2025, Taxonomic Revision of the Paepalanthus canastrensis Complex (Eriocaulaceae) with Descriptions of Four New Species from Serra da Canastra, Phytotaxa 708 (2), pp. 145-166 : 153-155

Paepalanthus versatilis Sauthier & Tissot-Sq., sp. nov. ( Figs. 6–7 )

Diagnosis: — Paepalanthus versatilis differs from P. canastrensis by the stramineous to light-brown involucral bracts as long as the high of the capitula or almost its high (× brown to dark brown, at least one third shorter than the capitula) and by the remnants of vascular bundles as castaneous fibers (× deciduous or absent in straw fibers). From P. aulociliatus , this species differs from the lanceolate leaves, ovate internal involucral bracts and by the non-ciliated floral tube (× narrow-triangular, orbiculate, ciliated floral tube). From P. myriothrixus , it can be distinguished by the absence of a tuft of trichomes just below the hydathodes area (× presence).

Type: — BRAZIL. Minas Gerais: São Batista do Glória: Parque Nacional da Serra da Canastra, 10 km da portaria de Sacramento, 57 km de Jaguarê (Jaguari), nascentes do córrego Mata Cavalo, elev. ca. 1300 m, 01 October 1999, F.N. Costa 113 et al. (Holotype SPF barcode SPF00138554!, isotype HUIRB!).

Perennial herb, 14.5–32.2 cm high, habit in rosette, stem vertical, internodes shorter than 0.5 cm, remnants of vascular bundles persistent with castaneous fibers. Leaves 11.8–31.4 × 0.6–1.35 cm, spirallate, flat, lanceolate to narrow-triangular, leathering, with superficial wax; apex acute to attenuate, glabrous below the hydathodes area; margins not ciliated; leaf base with a paler color on the adaxial surface, membrane rarely present, up to the basal third of leaf. Spathe membranaceous, almost transparent, very short and inconspicuous with 0.29–1cm long, ciliated, truncate to bidentate. Scapes 10–25.5 cm long, scarcely pilose, branched, grouping free capitula. External involucral bracts lanceolate to ovate, as long as the capitulum, glabrous to scarcely pilose with deciduous trichomes on the back, stramineous to light-brown, obtuse to acute. Internal involucral bracts ovate, scarcely pilose with trichomes deciduous on the back, brown, obtuse to acute. Flowers trimerous. Staminate flower 3–4.5 mm long; floral bracts 3–4.5 mm long, lanceolate, dorsally glabrous but densely pilose towards the apex with subclavate trichomes, cuspidate to acuminate; sepals 2.8–4 mm long, oblanceolate to obovate, connate until the middle or up the basal one third, obtuse to acute; floral tube not ciliated, hyaline. Pistillate flower 3–4.5 mm long, pedicellate; floral bracts 3.3–4.5 mm long, lanceolate, dorsally glabrous but densely pilose towards the apex with subclavate trichomes, obtuse, acute or acuminate; sepals 2.6–4.5 mm long, oblanceolate, connate at the base, obtuse to acute; petals 2.3–3.5 mm long, obovate, obtuse to acute; gynoecium with nectariferous branches shorter than the stigmatic branches. Fruit loculicidal capsule. Seeds 1.5–1.6 mm, reddish brown, tegument forming white appendages after hydration.

Habitat, distribution and conservation: — Paepalanthus versatilis is restricted to Chapadão do Diamante ( Fig. 7 ), occurring in the campos rupestres, in dry sandy to wet clayey soils. Paepalanthus versatilis has an AOO of 24 km 2, which indicates Endangered (EN) status, and an EOO of 11 km 2 ( Fig. 14 ), with a Critically Endangered (CR) status. Due to the impact of fire ( Fig. 15 ), which most intensively affects the young individuals in the population, with an estimate of less than 50 reproductively mature individuals, it should be indicated as CR, using the B2ab(iii); D criteria.

Morphologic and taxonomic comments: —Individually or in a small set, the traits of P. versatilis are shared with the remaining P. subg. Platycaulon species of the Serra da Canastra, making it possible to confuse them. The general aspect and plant size are compatible with P. canastrensis , P. myriothrixus and P. aulociliatus . However, these similarities are surpassed by a set of traits that enable their differentiation. The stramineous to light brown external involucral bracts, which are as long as or almost as high as the capitulum, and the red remnant of vascular bundles differentiate it from P. canastrensis . The absence of tufts of trichomes and the color of the external involucral bracts distinguish it from P. myriothrixus , while the lanceolate to ovate internal involucral bracts and the non-ciliated floral tube set it apart from P. aulociliatus .

The external involucral bracts can vary within the population and among the capitula in the same individual. They range from stramineous to light brown, reaching the same height as the capitulum, or rarely brown, measuring at least one third shorter than the capitulum. In the latter case, it is also possible to find bracts as long as the capitulum in the same individual, and differentiate P. versatilis from P. canastrensis by the red remnant of vascular bundles in the base of the rosette.

Etymology: — Paepalanthus versatilis is named from the Latin word versatilis , meaning something versatile ( Rizzini 1955), which matches its morphological range, exhibiting attributes in common with all other P. sect. Divisi from Serra da Canastra. These attributes, however, are presented in a unique combination, distinguishing it from the others.

Additional specimens examined: — BRAZIL. Minas Gerais: São Roque de Minas, Parque Nacional da Serra da Canastra , 20º13’22’’S 46º27’06’’W, elev. 1493 m, 19 August 2014, E. Melo 12921 et al. (HUEFS) ; Próximo à Garagem de Pedras , 20º13’00’’S 46º28’31’’W, elev. 1474 m, 30 September 2010, R. Rodrigues da Silva 1137 (SPF, HUEFS) ; Chapadão do Diamante , após a antena, 9 July 1996, J.N. Nakajima 1917 et al. (SPF, HUFU image) ; Córrego da Fazenda, morro após o vale do rio São Francisco , 26 September 1995, R. Romero 2864 et al. (SPF, HUFU image) ; 2 km após portaria de São Roque, lado direito da estrada, 20º14’18.73’’S 46º26’49.24’’W, elev. 1373 m, 13 November 2017, L.J. Sauthier 44 & R. Ramos (SPF); Torre do Bentim , entrada à direita a 3 m do curral de pedras, 20º12’45.41’’S 46º28’32.82’’W, elev. 1485 m, 15 November 2027, L.J. Sauthier 59 & R. Ramos (SPF, HUIRB) ; Estrada SacramentoSão Roque de Minas , lado direito, 20º13’24.66’’S 46º27’35.6’’ W, elev. 1457 m, 16 March 2020, L.J. Sauthier 183 et al. (SPF, HUIRB) ; 20º14’16.45S’ ’ 46º26’47.99’’W, elev. 1383 m, 16 March 2020, L.J. Sauthier 184 et al. (SPF, HUIRB).

Figures

FIGURE 6. Paepalanthus versatilis, where a) habit; b) castaneous remnants of vascular bundles in the rosette indicated by the red arrow; c) membranaceous spathe indicated by the red arrows; d) leaf apex; e) inflorescence; f) capitulum; g) external involucral bract; h) internal involucral bract; i) staminate flower; j) floral bract of the staminate flower; k) opened floral tube and sepals; l) pistillate flower; m) floral bract of the pistillate flower; n) sepals of the pistillate flower in adaxial view on the left and abaxial view on the right; o) fruit; p) petal of the pistillate flower with staminode indicated by the white arrow; q) gynoecium; r) seed. Photos a, c from L.J. Sauthier & R. Ramos 59; b, d, f-r from F.N. Costa 113 et al. (SPF); e from L.J. Sauthier & R. Ramos 44. Photos a, c-r by L.J. Sauthier and M.L. Tissot-Squalli; b by E.C. de Lemos. Scale bars equal to 1 mm, except for the staminode and seed in p and r equal to 200 μm.

FIGURE 7. Geographical distribution of Paepalanthus versatilis in the Serra da Canastra region.

FIGURE 14. Fire recurrence historical series (1980-2020), Area of Occupation (AOO) and Extent of Occurrence (EOO) of Paepalanthus subg. Platycaulon species from the Serra da Canastra region.

FIGURE 15. Impact of the fire on the Paepalanthus subg. Platycaulon species in Serra da Canastra region, measured by recurrence of burned area.