Pavonia neuropetala M.Rondon-Anjos, A.K.Koch & T.S.Cout., 2025

Pavonia neuropetala M.Rondon-Anjos, A.K.Koch & T.S.Cout. sp. nov.

( Figure 1 View FIGURE 1 , 2 View FIGURE 2 ).

TYPE:— BRAZIL. Mato Grosso: Porto Estrela, Estação Ecológica da Serra das Araras , 15º39’2,33954’’ S, 57º12’26,4788’’ W, 04 March 2023, fl. fr., M.V. Rondon-Anjos et al. 236 (holotype: UFMT!; GoogleMaps isotypes: UFP!, RB!) GoogleMaps .

Diagnosis: — Pavonia neuropetala is morphologically similar to P. angustifolia Bentham (1841: 119) sharing the reduced number of epicalyx bracteoles and the pink corolla, but it differs from it mainly by the ovate leaf blades (vs. elliptic to narrowly linear in P. angustifolia ), and the calyx 4–6 mm long (vs. 10–13 mm) and staminal tube 12 mm long (vs. 25–30 mm).

Description: —Shrub 40–50 cm tall. Branches hirsute, trichomes long-simple and hyaline 1.8–2.3 mm long, mixed with short-simple, hyaline and vinaceous, 0.3–0.4 mm long and glandular stalked ca. 0.3 mm long, sparse and glandular sessile. Leaves simple, spirally arranged; stipules 2–3 × 1 mm, linear, erect, hirsute, trichomes simple, apex acute, usually caducous; petiole 3–4 cm long, terete, but slightly plane at the base, densely hirsute, trichomes similar to the branches, but with a longitudinal line composed of short-simple and hyaline trichomes; leaf blade (1.5–)2–7.5 × 1.5–5 cm, ovate, entire, discolorous, base cordate, margins serrate, apex acute, adaxial surface pubescent, trichomes longand short-simple, densely distributed, and stellate, sparse, abaxial surface canescent, trichomes long- and short-simple, stellate and 3–4-radiate, margins ciliate with trichomes simple, vinaceous; venation actinodromous, 2–3 pairs of basal veins. Flowers solitary, axillary, pedicel 3.4–3.5 cm long, articulate to 4–5 mm below the calyx, hirsute, trichomes glandular stalked, vinaceous, hyaline; epicalyx 6–8-bracteolate, bracteoles 3–6 × 0.5–1 mm, linear to oblanceolate, hirsute in both surfaces, trichomes simple, hyaline, vinaceous. Calyx campanulate, 4–6 × 7.5 mm, hirsute, trichomes simple, lobes 2–3 × 3 mm, ovate, apex acute, margins ciliate, apex ciliate, trichomes simple, vinaceous. Petals pink to light pink, basal spot dark pink, 8–10 × 7 mm, obovate, base adnate to the staminal tube, claw glabrous, adaxial surface glabrous, abaxial surface sparsely strigose, trichomes 3-radiate, apex rounded to truncate, lightly emarginate; venation white, crass, conspicuous, specially at the base, yellow when herborized. Stamens fused into a staminal tube, white, ca. 12 × 2 mm, glabrous, 5-dentate apically, filaments free only at apex, ca. 1–2 mm long, anthers 0.5 mm long, white. Gynoecium 5-carpelar, ovary ca. 2 × 1 mm, villous, trichomes simple, styles free, 5–6 mm long, glabrous, stigmas 10, capitate, pubescent. Schizocarp ca. 3 × 4 mm, villous, trichomes simple, reticulate, mericarp 5, ca. 2.5–3 × 2.5 mm, triangular, muticous, indehiscent; seed 1 per mericarp, 2–2.2 × 1.5 mm, obovoid, smooth, glabrous.

Etymology: —The epithet refers to the notably conspicuous veins on the petals.

Distribution, habitat and phenology: — Pavonia neuropetala is endemic to the state of Mato Grosso, Brazil, and is known only by the populations in Estação Ecológica da Serra das Araras ( Figure 3 View FIGURE 3 ). This area is situated in the Cerrado domain, in the transition zone between the Amazonia and Pantanal domains. This ecological station is the only federal protected area that contains an ecotone of three phytogeographic domains, enabling the formation of different phytophysiognomies, from open vegetation to forests, in elevations reaching up to 2,000 m a.s.l. (ICMBio 2016). The climate in the region is Köppen’s Aw, characterized by a hot, humid and rainy period in summer, and dry period in winter, with average annual precipitation of 800 to 1,200 mm (ICMBio 2016). Pavonia neuropetala inhabits Cerrado sensu stricto areas in Estação Ecológica da Serra das Araras, at elevations of up to 798 m, always associated with rocky soil. Specimens were found with flowers and fruits between March and May.

Conservation status: — Pavonia neuropetala is known from a few populations representing five occurrence records, all in Estação Ecológica da Serra das Araras. Although it occurs within a protected area, its Area of Occupancy (AOO = 12 km 2) and Extent of Occurrence (EOO = 15.62 km 2) are low, conferring some threat to this species, such as habitat loss caused by uncontrolled fires. According to Durigan & Ratter (2015), changes in the fire use regime can cause a homogenization of the Cerrado landscape, with consequent dominance of grasses. This is truly important from a local perspective. In 2024, ESEC Serra das Araras was hit by fires that probably originated from neighboring farms. The uncontrolled fire affected more than 50% of the area, causing a significant loss of local flora and fauna. Pavonia neuropetala is a small shrub up to 50 cm tall, thus making the species more susceptible to harm. We suggest classifying Pavonia neuropetala as Critically Endangered (CR), using the criteria B1ab (i, iv, v).

Additional specimens examined (Paratypes): — BRAZIL. Mato Grosso: Porto Estrela, Estação Ecológica Serra das Araras , 16 May 2011, fl., C.M.S.C. Brazão & N.A.U.S. Silva 119 ( UFMT 40097 !); ibidem, 27 March 2023, fl., M.V. Rondon-Anjos & I.M. Melquíades 05 ( UFMT!); ibidem, 15 March 2024, fl., M.V. Rondon-Anjos & I.M. Melquiades 312 ( UFMT!); ibidem 15 March 2024, fl., M.V. Rondon-Anjos & I.M. Melquiades 313 ( UFMT!); ibidem 14 May 2024, fl. fr., M.V. Rondon-Anjos et al. 352 ( UFMT!); ibidem 14 May 2024, fl., M.V. Rondon-Anjos et al. 353 ( UFMT!).

Discussion: — Pavonia neuropetala is placed in subgenus Pavonia due to the mericarps longer than the column, and in section Lopimia due to the habit, erect stipules, leaf blades ovate and cordiform at the base, and pink petals up to 10 mm long ( Fryxell, 1999). This section contains 27 species ( Fryxell 1999, Krapovickas 2012), six of which occur in Mato Grosso (Flora e Funga do Brasil 2025 [continuously updated]), including the new species.). One of the distinctive features of section Lopimia is the epicalyx with 10–24 bracteoles, although he described that P. angustifolia has 7–9 bracteoles ( Fryxell 1999). One of the features that distinguishes the new species from others in the section is the reduced number of bracteoles, which varies from 6–8. This characteristic is also found in P. angustifolia (7–10, according to Esteves 2001), P. almasana Ulbrich (1924: 43) , P. boisina Krapovickas (2012: 61) , and P. botumirima Krapovickas (2012: 63) , with 7–10 ( Esteves 1998b, Fryxell 1999). The new species differs from the other four mainly by the branches with simple trichomes (and glandular) and obovoid seeds (vs. only stellate trichomes, accompanied or not by glandular trichomes, and reniform seeds) ( Table 1 View TABLE 1 ). Pavonia neuropetala is also characterized by the petals with 3-radiate trichomes on the abaxial surface and remarkable prominent white veins in fresh materials, which turn yellowish when dry.

Pavonia neuropetala differs from the other species by the shorter calyx, corolla, staminal tube and mericarps ( Table 1 View TABLE 1 ).

In relation to P. almasana , it is morphologically close mainly due to pink petals, but P. neuropetala has a darker pink basal spot on them (vs. vinaceous to purplish). Pavonia boisiana and P. botumirima have orangish and reddish petals, respectively.

In Estação Ecológica Serra das Araras, Pavonia neuropetala is sympatric with P. hexaphylla (S. Moore) Krapovickas (1983: 269) , with which it shares the pink corolla, leaf blades ovate and discolorous, and the number of bracteoles, but they can be differentiated by the bracteoles 3–6 mm long in P. neuropetala (vs. 10–14 mm), 3-radiate trichomes on the abaxial surface of the petals (vs. both surfaces with simple trichomes), and smooth seeds (vs. striated). Furthermore, this striated seed pattern places P. hexaphylla in section Asterochlamys ( Fryxell 1999: 132) .

Geographically, Pavonia neuropetala is restricted to the state of Mato Grosso, more precisely Estação Ecológica Serra das Araras, occurring in Cerrado s.s at higher elevations, always close to rock outcrops. Pavonia angustifolia has a wider distribution, occurring in Bolivia, Colombia, Guyana, Venezuela ( Fryxell 1999) and in Brazil in the states of Roraima, Goiás, Mato Grosso do Sul, Mato Grosso and Minas Gerais, occurring in Cerrado s.l., Riparian Forest and/or Gallery Forest ((Flora e Funga do Brasil, 2025) [continuously updated]). Pavonia almasana is endemic to Bahia, in northeastern Brazil, and is found in highland rocky fields, Riparian Forest and/or Gallery Forest ( Esteves 1998a; Flora e Funga do Brasil, 2025 [continuously updated]), P. boisiana is restricted to Goiás, in Cerrado and Riparian Forest, and P. botumirima is endemic to Minas Gerais, also found in Cerrado areas ( Krapovickas 2012).

In the state of Mato Grosso, Pavonia neuropetala is sympatric with five other species of section Lopimia . Differences among them are provided in the identification key below.