Eugenia paranapanemensis Valdemarin & Mazine

Karinne S. Valdemarin, Paulo H. S. A. Camargo, Daniele Janina Moreno, Vinicius Castro Souza, Eve Lucas, and Fiorella F. Mazine (2022). Eugenia paranapanemensis (Myrtaceae), The Pitanga-amarela, and a Key to Eugenia sect. Eugenia Species from São Paulo Sta

Type

BRAZIL. São Paulo, Paranapanema, Fazenda São Roque, 23_34901.999S, 48_39919.399W, fragmento de Floresta estacional, 13 August 2019, fl., P.H.S.A. Camargo & D. J. Moreno s.n. (holotype: SORO! (SORO 7948); isotype: ESA!).

Diagnosis

Eugenia paranapanemensis resembles E. uniflora but differs in its height, reaching 27 m (vs. up to 6 m); rugose bark (vs. smooth); leaves with petioles 5–7 mm long, leaf blade bases acute or cuneate, rarely obtuse (vs. petioles 1.5–4 mm long, leaf blade rounded or obtuse, rarely subcordate) and secondary veins confluent with the marginal vein (vs. first pair not confluent with the innermost marginal vein); flowers with smooth and pubescent hypanthia (vs. costate and glabrous); fruits are smooth, yellow, with up to 6 seeds (vs. smooth or costate, reddish or dark red, and up to 2 seeds). Eugenia paranapanemensis also resembles E. brasiliensis but is distinguished by its height of about 27 m (vs. up to 15 m); bark peeling in papyraceous regular grey to whitish plates (vs. in irregular grey to black plates); leaves up to 75 mm long (vs. 57–140 mm); flowers with pubescent hypanthia (vs. glabrous); fruits yellow with up to 6 seeds (vs. dark purple or rarely yellow with up to 2 seeds).

Habit

Tree up to 27 m tall

Ecology

The new species is known only from the type locality. It grows in the Semideciduous Forest of the Atlantic Forest Domain at about 630 m a. s. l., where the average annual rainfall is up to 1400 mm, concentrated in the wet summer season (December to March) and the mean annual temperature is 18_C (Cielo-Filho et al. 2009).

Distribution

Brazil, Atlantic Forest Domain.

Phenology

Flowering specimens were collected in August, fruiting specimens in August and October.

Conservation

Eugenia paranapanemensis is only known from its type locality, where three individuals were recorded. The new species occurs within the second most threatened biogeographical region of the Atlantic Forest, with only 7% forest cover remaining (Ribeiro et al. 2009) and in a very fragmented area, under intense pressure, especially from cattle farming and the production of corn, soybeans, cotton, and cereals. The flora of the city of Paranapanema is not well enough collected with ca. 1.2 specimens registered per km2 (ca. 1200 specimens deposited at herbaria available in CRIA (2021), http://inct.splink.org.br/), less than half of the number proposed for sufficiently collected tropical areas by Shepherd (2003). The region may face losses in habitat and/or quality in the absence of a long-term conservation strategy. If a formal conservation assessment were performed, the small area of occurrence (AOO ffi 4 km2) of Eugenia paranapanemensis would likely result in a Critically Endangered status, according to IUCN Red List criteria B2 ab(i, ii, iii, iv) based on expected decline of its extent of occurrence (i) and area of occupancy (ii), as well as habitat quality (iii) and number of locations (iv). Vernacular Name—Pitanga-amarela.

Etymology

The epithet refers to the type locality, the city of Paranapanema in the São Paulo state, Brazil.

Note

The new species is assigned to Eugenia sect. Eugenia based on its morphological features as presented above. Considering all species of this section occurring in São Paulo state, Eugenia paranapanemensis is easily distinguished in its combination of flowers with smooth and pubescent hypanthia and fruits that are yellow when ripe. Other remarkable features of the new species are its height, reaching up to 27 m, and whitish, rugose bark peeling in papyraceous regular plates. During fieldwork, plants were visited by several bird species such as Penelope superciliarisGmelin, Ramphastos toco Pallas, and Tangara Brisson spp. that fed on the fruits and probably dispersed the seeds. Seeds planted immediately when pulped have a high germination rate (70%) (P. H. S. A. Camargo pers. obs.). In the type locality, an abundance of seedlings is not reflected in an abundance of saplings and adult individuals (D. J. Moreno and P. H. S. A. Camargo pers.obs.) suggesting there is some local limitation to recruitment (Muller-Landau et al. 2002).