Peperomia asarifolioides García-Martínez & Beutelspacher, 2018

García-Martínez, Roberto, Beutelspacher-Baigts, Carlos R., Posada, Ricardo Callejas- & Mathieu, Guido, 2018, Two new lithophytic species of the genus Peperomia (Piperaceae) from the state of Chiapas, Mexico, Phytotaxa 338 (1), pp. 109-116 : 110-112

Peperomia asarifolioides García-Martínez & Beutelspacher sp. nov. ( Fig. 2 & 4 ).

Peperomia asarifolioides is morphologically close to P. asarifolia Schlechtendahl & Chamisso , to which it resembles in general habit, in leaf shape and in the presence of a small tuber. It differs by the presence of leaves and flowering sympodial branches both arising from the tuber, by the pedicellate fruits and by the lack of densely distributed orange hyaline dots on leaves, floral bracts and fruits as seen in P. asarifolia .

Type:— MEXICO. Chiapas, Municipality La Concordia, Finca Arroyo Negro, cascada trail, 15°50’8.31”N, 93°2’30.15”W, 1336 m, montane cloud forest, on volcanic rock near waterfall, growing with Achimenes erecta , Costus sp. and Peperomia lanceolatopeltata , 25 Oct 2016 (fl, fr), C. R. Beutelspacher 3565 (Holotype: HEM!).

Terrestrial lithophytic herb, up to 32 cm tall when flowering ( Fig. 2 & 4 ). Tuber underground or partly exposed, irregularly shaped or rough-globose, up to 2.2 × 1.8 cm, with fibrous roots all over its surface but mainly at the apex. Leaves of two types, the largest ones, 1–3 (–5) per plant and arising directly from the tuber, the smaller ones, alternately positioned on sympodial flowering branches ( Fig. 2a & b ), these branches also arising from the tuber, simple or with 1–2 short side branch(es) from a leaf axil; lamina wide ovate to almost orbicular, 2–9.5 × 1.8–7.5 cm, variable in size, rather uniform in shape, symmetric, equilateral at the base ( Fig. 2c ), cordate, lobate, lobes shorter than petiole, divergent, rounded, leaving a wide shallow sinus, apex acute to short acuminate, slightly pubescent adaxially near the apex, trichomes thin, erect and short (3–4 cells), glabrous abaxially, margin ciliate, sparsely and unevenly olive green dotted, 7–11-palmately-nerved or some leaves pinnately nerved, one pair of secondary nerves diverging from the main nerves above the middle, main nerves diverging at angles of 45–80 degrees, slightly curved, ascending and almost reaching the apex, dichotomously branching towards the margins, minor veins of third and fourth order, scarcely visible, all nerves more or less impressed adaxially, raised and prominent abaxially, thin membranous when living and dried, green adaxially and pale green abaxially when living, greenish or dark greenish when dried; petioles of vegetative leaves very long, 10–15 cm, those on sympodial branches short, 1–2 cm, uppermost leaves sessile, petioles striate to winged when living, glabrous, not dotted, white to greenish when living and dried. Inflorescences restricted to 1–3 sympodial branches of 12–19 cm long, erect or semi-erect, terete, glabrous, not dotted, white when living, 1–6 spadices per branch, the spadices solitary or 2–3 together on a common peduncle of ca. 7 cm long, the individual peduncle of each spadix 1–3 cm long, without bracteoles but often arising from the axil of a sessile, reduced leave at one of the uppermost nodes of the sympodial branches; rachis 10–17 cm long, 0.3 cm diam., erect in anthesis, irregularly curved in fruit, obtuse at apex, glabrous, white in flower and fruit, not hyaline dotted. Flowers ( Fig. 2d ) widely spaced in anthesis and fruit; pedicel 2 mm long, slender, rigid, glabrous, lacking hyaline dots, sometimes two flowers on a common pedicel; floral bract 0.6 mm diam., wide ovate, apex acuminate, sessile at basis of pistil, whitish, almost entirely covering ovary in anthesis; ovary ellipsoid, white, surface granular, style conical, stigma apical; stamens as long as fruits, anthers reniform and minute, 0.4 mm on slender filaments, 0.7–1 mm long. Fruit pedicellate, ellipsoid, ca. 1 mm long, surface granulose and covered with sticky papillae, green.

Etymology— The Greek suffix ‘-oides’ of the specific epithet refers to a ‘resemblance’, in this case with P. asarifolia Schlechtendahl & Chamisso.

Distribution and ecology— The species appears to have a very limited distribution. All known collections were made within the boundaries of the municipalities of La Concordia and Villacorzo in the Sierra Madre of Chiapas, elevation 1080–2200 m. The main vegetation type is montane cloud forest, alternated with pinus-oak forest. The geological formation in the region is characterized by Precambrian and Paleozoic extrusive rock masses. The dominant soils are leptosols and regosols, characterized by very thin horizons typical for the mountainous complexes of Chiapas. It is likely that the species can also be found in Guatemala, in similar habitats in the mountain chain that is the continuation of the Sierra Madre of Chiapas. However, screening over 2400 Guatemalan herbarium specimens of Peperomia did not reveal the species so far.

Paratypes — MEXICO. Chiapas, Municipality La Concordia, Finca Arroyo Negro , cascada trail, 15°50’8.31”N, 93°2’30.15”W, 1336 m, montane cloud forest, 25 Oct 2016, R. García Martínez 116 ( HEM!) ; ca. 2 km from ranch El Vergel, 15°48’46.5”N, 93°03’25.1”W, 1620 m, tropical rain forest, 6 Jul 2005, J. Martínez Meléndez 950 ( CHIP!, HEM!) ; 2.1 km SW of Arroyo Negro , 15° 49’20”N 93°02 27”W, 2115 m, montane cloud forest, 23 Jul 2014, M. G. Díaz M. 1519, ( CHIP!) ; 1.2 km from Arroyo Negro , N of waterfall, 15°50’08”N 93°02’29”W, 1246 m, tropical rain forest, 18 Jul 2014, M. G. Díaz M. 1212 ( CHIP!) ; Finca Arroyo Negro , 15°50’45”N 93°02’42”W, 1084 m, conifer forest, 10 Jul 2014, M. G. Díaz M. 1342 ( CHIP!, MEXU!) ; ca. 3 km from ranch Santa Elena , 15°45’26”N 93°01’25”W, 1542 m, tropical rain forest, 06 Nov 2006, J. Martínez Meléndez 1528 ( HEM!) ; Cerro Cebú , 15°49’24.4”N 93°02’44”W, 2200 m, montane cloud forest, 17 Jul 2005, J. López Chagala 54 ( HEM) ; El Triunfo Reserve, Poligone 4, ranch San Martín , 50 km S of ranch La Independencia, 15°45’82”N 93°05’24”W, 2078 m, montane cloud forest, 8 Jul 2001, R. Martínez Camilo 126 ( HEM!) ; mountain near ranch Santa Cruz , 2 km N of ranch San Martín, tropical rain forest, 1430 m, 18 Jul 2001, F. Hernández Najarro 608 ( CHIP!, HEM!) ; 3.5 km from ranch El Vergel, 15°48’44.6”N 93°04’27”W, 1900 m, montane cloud forest, 13 Jul 2005, J. Martínez Meléndez 997 ( HEM!) ; Municipality Villacorzo , cerro La Peña, al W del ejido Sierra Morena. 16°9’51’’N. 93°36’8’’W, 1450 m, tropical rain forest, 19 Oct 2002, L. Alvarado C. 592 ( MEXU!) ; Ejido Sierra Morena , montane cloud forest, 16°8’25”N 93°33’20”W, 1320 m, 12 Jul 2004, A. Reyes García 7138 ( MEXU!) .

Figures

FIGURE 2. Peperomia asarifolioides: a & b) habit of the plant c) leaf abaxial d) flowering rachis (Based on C. R. Beutelspacher 3565 & R. García Martínez 116 [HEM]).

FIGURE 4. Peperomia asarifolioides sp. nov. growing in situ near to Finca Arroyo Negro, La Concordia, Chiapas.