Stachytarpheta ratteri (S.Atkins) P.H.Cardoso, 2022

Cardoso, Pedro Henrique, Neto, Luiz Menini, Somavilla, Nádia Silvia & Trovó, Marcelo, 2022, A morphometric approach and recircumscription of the Stachytarpheta longispicata complex (Verbenaceae), European Journal of Taxonomy 833, pp. 12-45 : 38-41

Stachytarpheta ratteri (S.Atkins) P.H.Cardoso comb. and stat. nov.

Figs 6M–O , 7I–J , 8I–J , 13

Stachytarpheta longispicata subsp. ratteri S.Atkins, Kew Bulletin 60: 231 ( Atkins 2005), basionym.

Material examined

Type BRAZIL – Distrito Federal • Fazenda Água Limpa near Vargem Bonita; 15 Mar. 1976; J.A. Ratter & S.F. da Fonseca 2775; holotype: K [ K000065168 ] web!; isotypes: NY [ NY00956498 ] web!, UB web!, UEC n.v .

Representative specimens

BRAZIL – Distrito Federal • “ Brasília área do Zoobotânico ”; 10 Jan. 1967; A.P. Duarte 10163; RB • “ Brasília, between University of Brasília and Lago Paranoá ”; 11 Apr. 1968; D. Philcox & E. Onishi 4767; K, UB • “ Brasília, Chapada Contagem ”; 5 Feb. 1987; J.R. Pirani et al. 1650; K, SPF • “ Brasília, estrada da Península perto do Clube do Congresso ”; 29 May 1965; D. Sucre 25; RB • “ Brasília, campus da Universidade ”; 29 Sep. 1975; F.H. F. Oldenburger 1627; SPF • “ Brasília, Fazenda Sucupira ”; 6 May 1999; J.G. Faria 107; CEN • “ Brasília, Fazenda Sucupira ”; 18 Apr. 2007; G.D. Vale 457; RB • “ Brasília, Fazenda Sucupira ”; 13 Jan. 1998; A.B. Sampaio et al. 153; CESJ • “ Brasília, Jardim Botânico de Brasília ”; 13 Mar. 2020; P.H. Cardoso et al. 51; CESJ • “ Brasília, Brasília, Parque Ecológico Burle Marx ”; 7 Mar. 2021; B. Schindler & M. Figueira 56; CEN, CESJ • “ Brasília, Jardim Botânico ”; 10 Nov. 2009; W. Alkimim & J.B.A. Bringel 86; UB • “ Brasília, Parque Boca da Mata ”; 14 Jul. 1995; J.M. de Rezende 4; CESJ • “ Brasília, Parque Nacional ”; 22 Jan. 1978; A. Krapovickas et al. 33180; K • “ Brasília, Parque Nacional de Brasília ”; 14 Dec. 1990; P.C.M. Ramos 482; UB • “ Brasília, Parque Nacional de Brasília ”; 4 Nov. 1992; M. Barros et al. 2220; HUEFS, K • “ Brasília, Reserva do CPAC ”; 31 Jan. 2009; D.M. Ramos 1; CEN • “ Brasília, Reserva Ecológica do IBGE ”; 29 Mar. 2014; V.C. Souza et al. 38219.0; ESA • “ Brasília, Reserva Ecológica do IBGE ”; 24 Mar. 2016; V.C. Souza et al. 40214; RB • “ Brasília, Planaltina, CPAC – Embrapa”; 5 May 1980; J.A. da Silva 116; CEN • “ Brasília, Reserva Biológica de Contagem ”; 5 Mar. 2012; M.R.V. Zanatta 1230; RB • “ Brasília, rodovia Brasília-Sobradinho ”; 1 Apr. 1992; R.F. Vieira 1223; CEN • “ Brasília, Rodovia Sobradinho/DF ”; 15 Aug. 1999; G. Pereira-Silva 4234; CEN • “ Brasília, Saia Velha ”; 21 Feb. 2003; F. França et al. 4600; HUEFS . – Goiás • “ Cocalzinho de Goiás ”; 20 May 2006; L.B. Bosquetti 305; ESA • “ Cocalzinho de Goiás, Serra dos Pireneus ”; 24 Nov. 2007; P.G. Delprete 10414; NY • “ Corumbá de Goiás , estrada velha da cidade eclética para Anápolis ”; 31 Nov. 1990; R.F. Vieira 625; CEN • “ Luziânia, estrada Brasília-Luziânia ”; 20 Jul. 1990; E. de Melo 314; CEN • “ Pirenópolis, Fazenda Lavras do Abade ”; 8 Dec; 2018; G.M. Antar 2532; CEN • “ Pirenópolis, Serra dos Pireneus ”; 15 Jan. 1972; H.S. Irwin et al. 34156; NY • “ Pirenópolis, Parque Estadual da Serra dos Pireneus ”; 24 Feb. 2009; F. Almeda et al. 9520; UEC • “ Planaltina ”; 21 Apr. 2007; H.D. Ferreira 4589; UFG • “ Planaltina, Rod. Go-118”; 12 Jun. 1993; G. Hatschbach et al. 59296; MBM.

Description

Clump-forming shrubs 0.5–2 m tall, erect, much-branched or unbranched, stems cylindrical, pubescenttomentose, xylopodium present. Leaves opposite, patent, often conduplicate, sometimes with smaller leaves on the axils, petiolate; petiole 1.98‒11.35 mm long, woolly; blade 19.32–45.67 × 24.96–48.52 mm, fan-shaped or obovate, coriaceous, slightly discolorous, base truncate, rarely cuneate, decurrent into petiole, apex obtuse to rounded, sometimes emarginate, margin entire near the base, crenate-serrate towards the apex, lightly revolute, abaxially foveolate, tomentulose, veins evident forming a reticulate network, adaxially strigose with abundant small brown nectaries. Inflorescences 218.9–601.04 × 19.97– 28.44 mm, pendulous at the apex, rachis visible, pubescent-tomentose or lanate; bracts 6.13–9.51 × 1.11– 1.77 mm, light green, triangular or narrowly triangular, apex acuminate or caudate, abaxially sericeous. Flowers pedicellate, pedicel 1.03–2.27 mm long, sericeous; calyx tube widened at the apex, 11.72‒17.59 × 4.49–7.13 mm, light green, externally sericeous at base, becoming strigose at apex, 5-toothed; corolla salmon, tube 14.06‒22.02 mm long, externally with pedicellate glandular trichomes. Fruits 0.42‒0.5 cm long, castaneous, external surface reticulate, with thin and flat commissure, apex rounded with short stylopodium, prominent attachment scar, separating into two cluses, covered by the persistent calyx.

Distribution, habitat and phenology

Stachytarpheta ratteri is endemic to the Cerrado domain in the states of Goiás and Distrito Federal ( Fig. 5 ), growing in campos rupestres, campos sujos (shrubby grasslands), campos limpos (grasslands), and disturbed areas. Its populations are generally large-sized, but fragmented. Found fertile throughout the year, except in October.

Proposed conservation status

Stachytarpheta ratteri has an estimated EOO of 7 537.960 km 2 and AOO of 224 km 2. Its populations are generally large-sized, but fragmented. The species is recorded for several regions in Distrito Federal and some municipalities of Goiás, west of Brasília, including protected areas (Parque Estadual da Serra dos Pireneus and Parque Nacional de Brasília). In the state of Goiás, the increased frequency of illegal fires for agricultural purposes, mining activities, unorderly touristic activities, and invasive species represent the greatest threats for S. ratteri ( Salmona et al. 2014; Santos 2018; Castro 2019). In Brasília, the constant urban expansion ( Anjos 2015) is the most important threat to this species. Therefore, S. ratteri should be considered “Endangered” (EN), based on the B2ab(i,ii,iii) criteria ( IUCN 2022), due to its AOO <500 km 2, fragmented populations, and threats causing the continuous decline of its AOO, EOO and habitat quality.

Notes

Atkins (2005) characterised Stachytarpheta longispicata subsp. ratteri as a clump-forming shrub up to 2 m tall, with a xylopodium, unbranched, petiolate leaves, blades 30–50 × 25–40 mm, inflorescences up to 730 mm long, rachis not visible at apex, linear bracts ca 7 mm long, calyx ca 16 mm long, corolla orange to rusty, and tube ca 20 mm long. According to Atkins (2005), it represents the taxon most commonly associated with the name S. longispicata , with large leaves, long inflorescences, and restricted to Distrito Federal. When comparing our present circumscription with the one proposed by Atkins (2005), it is possible to observe differences in the size of the leaves and length of the inflorescences, bracts, calyx, and corolla. Once again, these inconsistencies about the size of the leaves are caused by the petiole and leaf-blade lengths being combined by Atkins (2005), while we present them separately. The author also described the inflorescences as being up to 730 mm long and the rachis not visible at the apex. However, during the analysis of the specimens cited by Atkins (2005), we observed that the inflorescences reach only up to 600 mm in length and that despite the flowers being more congested at the inflorescence apex (compared with S. longispicata ), the rachis is always visible.

Based on our morphometric analysis as well as qualitative characters, and geographic distribution, Stachytarpheta longispicata subsp. ratteri is elevated to the species rank. Therefore, S. ratteri can be differentiated from the remaining species of Stachytarpheta with pedicellate flowers by its leaf-blades large (19.32–45.67 × 24.96–48.52), coriaceous, with base frequently truncate, rarely cuneate, abundant small brown nectaries adaxially, sericeous pedicels, and calyx externally sericeous at base, becoming strigose towards the apex. Its distribution is expanded to the state of Goiás ( Atkins 2005; Cardoso & Salimena 2020).

Figures

Fig. 6. Comparison between the main characteristics of the species used in the identification key (photos taken under the stereo microscope). A, D, G, J, M. Adaxial indumentum of the leaf-blade. B, E, J, K, N. Abaxial indumentum of the leaf-blade. C, F, I, L, O. Indumentum of the rachis, bracts, pedicel, and calyx. A–C. Stachytarpheta brevibracteata (Moldenke) P.H.Cardoso (P.H. Cardoso & W.P. Leite 66). D–F. S. longipedicellata (Moldenke) P.H.Cardoso (P.H. Cardoso et al. 59); G–I. S. longispicata (Pohl) S.Atkins (P.H. Cardoso et al. 48). J–L. S. minasensis (S.Atkins) P.H.Cardoso (F.R.G. Salimena & P.H. Nobre 459). M–O. S. ratteri (S.Atkins) P.H.Cardoso (P.H. Cardoso et al. 51).

Fig. 7. Comparison between the pubescence of the leaves of the species (photos taken under electron microscope). A, C, G, E, I. Adaxial surface. B, D, F, H, J. Abaxial surface. A–B. Stachytarpheta brevibracteata (Moldenke) P.H.Cardoso (P.H. Cardoso & W.P. Leite 66). C–D. S. longipedicellata (Moldenke) P.H.Cardoso (P.H. Cardoso et al. 59). E–F. S. longispicata (Pohl) S.Atkins (P.H. Cardoso et al. 48). G–H. S. minasensis (S.Atkins) P.H.Cardoso (F.R.G. Salimena & P.H. Nobre 459). I–J. S. ratteri (S.Atkins) P.H.Cardoso (P.H. Cardoso et al. 51).

Fig. 8. Comparison between the pubescence of the calyx of the species (photos taken under electron microscope). A, C, G, E, I. The most basal part. B, D, F, H, J. The most apical part. A–B. Stachytarpheta brevibracteata (Moldenke) P.H.Cardoso (P.H. Cardoso & W.P. Leite 66). C–D. S. longipedicellata (Moldenke) P.H.Cardoso (P.H. Cardoso et al. 59). E–F. S. longispicata (Pohl) S.Atkins (P.H. Cardoso et al. 48). G–H. S. minasensis (S.Atkins) P.H.Cardoso (F.R.G. Salimena & P.H. Nobre 459). I–J. S. ratteri (S.Atkins) P.H.Cardoso (P.H. Cardoso et al. 51).

Fig. 13. Stachytarpheta ratteri (S.Atkins) P.H.Cardoso comb. and stat. nov. A. Habitat. B. Habit. C–D. Individuals showing details of the leaves and inflorescences, highlighting the short pedicels, bracts, calyxes, and corollas. Photos by Pedro Henrique Cardoso (A–B, D) and Maurício Mercadante (C).

Fig. 5. Distribution map of the five species recognised in the Stachytarpheta longispicata complex in the present study. The triangles represent localities sampled during fieldwork for the morphometric analysis.