Eugenia aeterna Mazine & Valdemarin, 2023

Mazine, Fiorella F., Valdemarin, Karinne Sampaio, Giaretta, Augusto & Sobral, Marcos, 2023, A new species of Eugenia sect. Eugenia (Myrtaceae) from Atlantic Forest in São Paulo, Brazil, Phytotaxa 585 (3), pp. 233-238 : 234-236

Eugenia aeterna Mazine & Valdemarin , sp. nov. ( Figures 1 , 2 )

Type:— BRAZIL. S „ o Paulo: Caraguatatuba, Parque Estadual da Serra do Mar , Núcleo Caraguatatuba , Trilha do Jequitibá, Floresta Ombrófila Densa, 27 September 2000, fl., I . Cordeiro, M. R. F . Melo & M. C. H . Mamede 2331 (holotype SP! [ SP028642 ]; isotypes: NY! [ NY00777088 ], RB! [ RB00308175 ], SPF! [ SPF00150415 ], SPSF) .

Diagnosis:— Eugenia aeterna has smooth hypanthium and is morphologically related to E. ligustrina ( Swartz 1788: 78) Willdenow (1799: 962) and Eugenia longipedunculata Niedenzu (1893: 81) being distinct from both by: cataphylls persistent until mature twigs, even in the vegetative phase of the plant (versus cataphylls deciduous), puberulent or pilose hypanthium (vs. glabrous hypanthium) and calyx lobes reflexed and appressed to the fruit (vs. calyx lobes erect in the fruit).

Tree 2–7 m tall. Bark smooth, peeling from trunk in coarse irregular grey to pink plates. Cataphylls persistent until mature twigs. Twigs slightly flattened when young, terete with age, the distal internodes 25–45 mm long, 1–1.5 mm in diam., exfoliating longitudinally on papillose irregular sheets, puberulent, glabrescent; trichomes whitish. Young leaves pubescent, glabrescent; trichomes brownish to whitish. Leaves opposite, petioles 2–15 × 1–1.5 mm, canaliculate, puberulent, glabrescent; trichomes brownish; blades 6–17.5 × 2.7–4.5 cm, elliptic, oblong or sometimes obovate, chartaceous, discolorous when dry, abaxially lighter, glabrous adaxially and puberulent or glabrous abaxially; oil glands 0.05–0.09 mm in diam., 4–8 per mm², inconspicuous adaxially and dark and raised abaxially; bases obtuse or cuneate, rarely rounded; apices acuminate, up to 10 mm long, sometimes slightly falcate; midvein adaxially sulcate and abaxially raised, glabrous adaxially and pubescent abaxially; trichomes brownish; secondary veins 22–26 at each side, leaving the midvein at angles of 60–70°, raised and glabrous on both surfaces; marginal veins two, the innermost 1–1.8 mm from the margin, the outermost up to 0.5 mm from the slightly revolute to revolute margin. Inflorescences terminal or lateral, auxotelic, racemiform, with two pairs of flowers and late vegetative proliferation, puberulent; bracts 2–20 × 2–9.5 mm, oblanceolate to narrowly oblanceolate, puberulent; trichomes brownish; persistent after anthesis; flowers with pedicels 16–35 × 0.5 mm, flattened, pilose; trichomes brownish; bracteoles ca. 6 × 1 mm, linear, deciduous at or after anthesis; ciliate, trichomes brownish to whitish. Flower buds 3–3.5 mm in diam., orbiculate to obovoid. Flowers with smooth, puberulent or pilose hypanthia; trichomes brownish to whitish; calyx lobes 4, free, of two equal pairs, 5.5–7 × 3–4.8 mm, ovate or oblong, apices acute or obtuse, puberulent on both surfaces; trichomes brownish, oil glands markedly evident; petals 4, 8–16 × 6–8 mm, obovate, glabrate and glabrescent on both surfaces, oil glands inconspicuous; trichomes brownish; staminal ring ca. 2 mm, rounded, puberulent to glabrous; stamens with filaments 10–13.5 mm, anthers 0.5–1 mm, oblong or globose, longitudinally dehiscent; style 8.5–12 mm, glabrous, stigma punctiform; ovary 2-locular, ovules not counted, locule internally glabrous. Fruits 11–13.5 × 9.5–11.5 mm, globose or oblate, smooth, glabrous, dark purple when ripe; seeds 1–3 per fruit, ellipsoid or globose, testa smooth, cotyledons fused with visible hypocotyl.

Distribution and Habitat: —The new species has been recorded in the Ombrophilous Forest of the Atlantic Forest Domain in the municipalities of Caraguatatuba and Ubatuba, S„o Paulo state, Brazil ( Figure 3 ).

Phenology: —Flowering specimens were collected from September to January, and fruiting from November to February.

Preliminary conservation status: — Eugenia aeterna is known from 13 gatherings in five localities within protected areas—Serra do Mar State Park. The species has an Extent of Occurrence (EOO) of ca. 176 km ² and an Area of Occupancy (AOO) of 16 km ², falling within the thresholds of the Endangered category, under the criterion B. However, Eugenia aeterna occurs only in well protected areas, and it is assumed that is not under any major threats or continuing decline. Therefore, Eugenia aeterna is classified here as Least Concern (LC), as does not meet all required criteria.

Etymology: —The epithet refers to the long-lasting cataphylls, being persistent until mature twigs.

Affinities: —This species had been identified as Eugenia plicata as recorded in several Brazilian herbaria. However, careful examination of the type in P revealed that Eugenia plicata is best circumscribed as Eugenia acutata Miquel (1849: 535) which has priority (see Giaretta et al. 2021). Thus, Eugenia aeterna is newly described here. The species is assigned to Eugenia sect. Eugenia based on its cataphylls subtending new twigs and racemose inflorescences with late vegetative proliferation. It is a quite distinct species, especially by its persistent cataphylls. See the generic key (specifically group F) presented in Flora do Brasil 2020 (Mazine et al. 2020) to distinguish the new species (erroneously named as E. plicata in that occasion) from other Eugenia sect. Eugenia species. Valdemarin et al. (2022) also presented a key to Eugenia sect. Eugenia in S„o Paulo state, Brazil. Additionally, it is worth noting that Eugenia aeterna is the entity treated by Valdemarin et al. (2022) as Eugenia aff. plicata .

Paratypes: — BRAZIL. S „o Paulo , Caraguatatuba , Parque Estadual da Serra do Mar, Núcleo Caraguatatuba, trilha dos tropeiros, 19 October 2000, fl ., R. S. Bianchini , F. Bonfim , F. O. Souza & G.L. Esteves 1485 ( SP 028643 !, SPSF). Ubatuba , Núcleo de Picinguaba, trilha da Casa da Farinha, 21 January 2001, fl ., P. Fiaschi & A. Lobão 589 ( SPF 144330 !); ibid., parcela E, subparcela 50, 08 May 2006, str ., M. C. R. Campos , M. A. Assis , A. Guaraldo & R. Belinello 483 ( UEC 023588 !); ibid., margens do Rio da Fazenda , 08 November 1992, fl ., M. Sanchez & F. Pedroni 400 ( RB 00309681 !); ibid., 23°22’S, 44°48’W, 07 November 1992, str ., M. Sanchez & F. Pedroni 2420 ( UEC 089582 !); ibid., 08 November 1992, fl ., M. Sanchez & F. Pedroni 345 ( UEC 016597 !); ibid., 23°22’S, 44°48’W, 24 November 1998, fr ., M. Sanchez & F. Pedroni 1867 ( UEC 029715 !); ibid., 23°22’S, 44°48’W, 08 November 1992, fr ., M. Sanchez & F. Pedroni 2419 ( UEC 089583 !); ibid., 23°22’S, 44°48’W, 24 November 1992, fr ., M. Sanchez & F. Pedroni 1868 ( UEC 029721 !); ibid., 09 February 1995, fr ., C.M. de O. Borges , F. R. de Melo , L. L. Rodrigues , L. A. F. de Jesus , S. de M. Soares & U. dos Santos s.n. ( VIC 15015 !); ibid., 13 January 1997, fr ., M. Sanchez & F. Pedroni 708 ( UEC 016600 !, SP 057048 !); ibid., 23°22’S, 44°48’W, próximo à trilha do Corisco , 12 January 1997, fl ., M. Sanchez & F. Pedroni 731 ( SP 057047 !, UEC 029717 !) .

Figures

FIGURE 1. Holotype of Eugenia aeterna Mazine & Valdemarin (Cordeiro 2331, SP).

FIGURE 2. Eugenia aeterna. A. Vegetative branch. B. Detail of the branch with distinctive persistent cataphylls. C. Branch with inflorescences in late stage. D. Branch with maturing fruits. E. Branch with mature fruit (Photo E by Miguel Nema Neto).

FIGURE 3. Geographic distribution of Eugenia aeterna in S„o Paulo state, Brazil.