Peperomia vazquezii G.Mathieu & D.Vergara-Rodríguez, 2015

Mathieu, Guido, Vergara-Rodríguez, Daniela, Krömer, Thorsten & Karger, Dirk Nicolaus, 2015, Peperomia (Piperaceae) novelties from Veracruz State, Mexico, Phytotaxa 205 (4), pp. 268-276 : 273-275

Peperomia vazquezii G.Mathieu & D.Vergara-Rodríguez , spec. nov. ( Fig. 1 (G, H, I), 4).

Peperomia hobbitoides T.Wendt simile, ab ea differt foliorum forma et statura maxime variabili, lamina utrinque glabra, margine eciliato, olore Coriandrum sativum L. foliorum nulla. Type:— MEXICO. Veracruz State, mun. Uxpanapa, Ejido Antonio Rodriguez Martin, Río Platanillo, cascada Las Cabañas, 17°11’N, 94°16’W, 180 m, 6 Jan. 2010, T. Krömer et al. 3854 (holotype BR!, isotype GENT!, MEXU!, XAL!).

Perennial lithophytic herb, to 20 cm tall, irregular red-brown rhizome. Stem terete, glabrous, watery light green, internodes 1.5–3.5 cm long. Leaves alternate, petioles (2–) 3–7 cm long, sulcate, glabrous, lamina very variable in shape and size, usually elliptic to ovate, length to 5 cm, width to 3.5 cm, sometimes lanceolate, length to 10 cm, width to 2 cm, apex acute, base obtuse to acute, basal leaves sometimes slightly cordate, length to 13, width to 10 cm, glabrous, margin eciliate, palmately 5–7(–9)–nerved, light green, somewhat whitish abaxially. Inflorescences compound, individual peduncles less than 1 cm, rachis filiform, 5–10 cm, glabrous, moderately densely flowered. Floral bract sessile to subsessile, inserted at the base of a distinct, wide conical pseudopedicel with an apical circular ridge, the pseudopedicel developing early, successively supporting the pistil, the young fruit and the mature fruit, bract round, centrally peltate, often hyaline glandular dotted. Ovary ellipsoid, style broad conical, glandular, or slightly papillate when dry, stigma terminal, from an apical pit in the style. Stamens with small anthers, filaments from the base of the ovary, from within the apical ridge of the pseudopedicel, indentations in that apical ridge where anthers are exserting. Fruit sessile, attached at the centre or slightly out of the centre of the fruit base, the base surrounded by the apical ridge of the pseudopedicel, axis of the fruit making an angle of (60–)70–80(–90)° with the rachis, fruit body ellipsoid, pericarp glabrous, glandular, or apically slightly papillate when dry.

Etymology— The specific epithet is chosen in honour of Santiago Mario Vázquez-Torres, Mexican botanist and cycad specialist at the Centro de Investigaciones Tropicales (CITRO—Universidad Veracruzana), who made several collections of this species. He was leader of a floristic brigade and one of the first to explore the poorly known tropical lowland rainforests of the Uxpanapa region in the early 70s of the past century.

Distribution, habitat and IUCN Red List category— All known collections are from a restricted area (AOO: 1,292.81 km 2) located in Uxpanapa in the south of Veracruz State. The species is considered as Vulnerable (VU) B2ab(ii,iii), because this region is strongly affected by deforestation and land use changes. Peperomia vazquezii is saxicolous, growing in rather humid conditions on limestone rocks at an elevation of 130– 250 m. Currently it is considered endemic to Veracruz. However it is very likely to be found also in the neighboring states of Chiapas and Oaxaca.

Relationships— Morphologically, P. vazquezii shows some resemblance with P. asarifolia Schlechtendal & Chamisso (1830: 75) (leaves suborbicular, base cordate, apex obtuse or rounded, spadices thicker, usually solitary or 2–4 together, reported from Mexico to Costa Rica), P. bernoullii de Candolle (1872: 367) (plants smaller, leaves elliptic to rhomboid, base rarely cordate, more homogenous in shape and size, spadices solitary or 2–4 together, apparently restricted to Guatemala and El Salvador) and P. hobbitoides Wendt (2003: 37) (leaves ovate, base generally cordate, indument adaxially and abaxially, margin ciliate, endemic to Veracruz). The leaves of the latter species give off a strong smell of cilantro when crushed. This is lacking in P. vazquezii . All mentioned species have a small rhizomatous tuber as their common feature. Preliminary phylogenetic results, based on chloroplast trnK-psbA gene cluster sequences (Symmank et al., unpublished data), confirm P. vazquezii to be related to P. asarifolia .

Additional specimens studied— Mexico. Veracruz State, mun. Hidalgotitlán, between Hermanos Cedillo and La Escuadra, along Soloxuchil river, 17°18’N 94°38’W, 150 m, 20 Oct. 1974, M. Vázquez 1260 ( IEB! [young inflorescences], XAL!) ; idem, 17°16’N, 94°37’W, 150 m, 9 Nov. 1974, M. Vazquez 1361 ( CIB!, IEB! [young inflorescences], XAL!) ; 1.5 km W of Campamento Hermanos Cedillo, along Soloxuchil river, 17°16’N, 93°36’W, 180 m, 11 Jan. 1975, M. Vázquez 1621 ( IBUG!, IEB! [fruiting], XAL!) ; mun. Minatitlán, hills up to 500 m S of Poblado 11, ca. 27 km E of La Laguna, 17°14’N, 94°16’W, 250 m, 21 Feb. 1981, T. Wendt et al. 2914 ( F! [lanceolate leaves], total number of duplicates mentioned: 22) ; mun. Minatitlán, Uxpanapa, 2 km N of Poblado 12, along road to Poblado 13, 17°14’N, 94°13’W, 130 m, 14 Mar. 1982, T. Wendt et al. 3670 ( F!, total number of duplicates mentioned: 3) ; mun. Uxpanapa, ejido Antonio Rodriguez, ca. 2 km above Río Platanillo and cascada Las Cabañas , 17°10’N, 94°17’W, 320 m, 2 Mar. 2010, D. Jimeno & J. Viccon 1268 ( BR!, GENT!, MEXU!, XAL!) .

Figures

FIGURE 1. Peperomia chazaroi (A, B, C). A) Miguel de Jesús Cházaro-Bazañez at type locality. B) Plants in habitat. C) Detail of the inflorescence. Peperomia parastriata (D, E, F). D) Plant in habitat. E) Inflorescences. F) Detail of the infrutescence. Peperomia vazquezii (G, H, I). G) Plants in limestone wall habitat. H) Inflorescences. I) Detail of the inflorescence. (Photographs A–H by T. Krömer; I by D.H. Jimeno-Sevilla).