Meriania neillii Humberto Mend., Acta Bot. Mex.

Fernandez-Hilario, Robin, Goldenberg, Renato & Michelangeli, Fabián A., 2023, A synopsis of Meriania (Melastomataceae: Merianieae) in Peru, Phytotaxa 602 (1), pp. 1-101 : 43-45

15. Meriania neillii Humberto Mend., Acta Bot. Mex. 128(e1734): 85 (2021).

Type:— ECUADOR. Napo: Southern slopes of Volcán Sumaco , Hollin – Loreto road, km 40, 1200 m, 11 Feb 1989 (fl.), D. Neill & M. Asanza 8887 (holotype: CAS [n.s.]; isotypes: MO! [barcode MO-1716563 ], NY! [barcode 02500066 ]) . ( Figures 36–37 ).

Comments:— Meriania hexamera Sprague has been traditionally considered a widely distributed species from Colombia to Peru. However, Mendoza-Cifuentes (2021) considers that M. hexamera is restricted to Colombia, and that the populations in Ecuador, Peru and southern Colombia correspond to a different species ( M. neillii ). According to him, the main differences between them would be the thickness of the stems (2.2–4 mm in diameter in M. neillii vs. 4–9 mm in diameter in M. hexamera ) and petioles (1–1.6 mm in diameter vs. 2–3.5 mm in diameter), and the pattern of venation (one pair of secondary veins vs. two pairs of secondary veins). However, some specimens cited under M. hexamera (e.g., Lawrence 420) by Mendoza-Cifuentes (2021) have thin stems and petioles. Likewise, Cuatrecasas 9139 and Franco 5312 have leaf blades with one pair of secondary veins and one pair of faint submarginal veins but were cited under M. hexamera . The only notable difference provided by Mendoza-Cifuentes (2021) is the apex of the ovaries (with lobes 0.3–1 mm long in M. neillii vs. with a ring 2–4 mm long in M. hexamera ). Because the delimitation between M. hexamera and M. nielli is unclear, we choose for the moment to refer to the Peruvian populations as M. neillii with reservations.

Meriania neillii is the most widely distributed Meriania species in Peru, and it is easily recognisable by its glabrous vegetative structures (rarely sparsely puberulent), leaf blades with entire margins and clearly parallel tertiary venation ( Fig. 36B–C ), and 6-merous flowers with spreading, reddish-purple corollas ( Fig. 37D ). It can be confused with M. franciscana , but this has adaxial projections (scutum) on the insertion of the petiole with the leaf blade (vs. absent in M. neillii ), 5-merous flowers (vs. 6-merous), and strongly dimorphic stamens (vs. isomorphic). Meriania neillii could be related to M. cuzcoana which also has 6-merous flowers and with similar corollas but see comments under M. cuzcoana for differences.

Peruvian populations of M. neillii usually have constant characteristics; the calyces do not have dorsal projections ( Fig. 36E ) and the leaf blades have slightly suprabasal venation. The leaf blades have obtuse to slightly rounded bases, however in many specimens the bases are slightly revolute giving the appearance of acute or cuneate bases. Nevertheless, there are some atypical specimens; Núñez & Alanya 13322 (fr.) has slightly narrowly cordate bases and Graham 6143 (fl.) has flowers smaller than usual (hypanthium plus calyx 6–6.5 mm long vs. 7.5–10 mm long). The venation in M. neillii usually consists of a main vein, one pair of secondary veins (lateral veins) and one pair of faint submarginal veins (e.g., Baldeón et al. 3069, Graham 6143, Núñez 13322). Nevertheless, in some specimens the submarginal veins are more evident, and there is a larger space between the submarginal veins and the margin of the leaf blades, where an additional third pair of faint veins can be observed (e.g., Campos & Corrales 3608, Campos & Díaz 4386, Monteagudo 15855). This latter pattern of venation can also be observed in the type of M. neillii . For this reason, we could consider that M. neillii may have up to two pairs of secondary veins.

Distribution and phenology:— Meriania neillii is widely distributed from southern Colombia to southern Peru, and occurs in almost all Peruvian Andean departments (from Amazonas to Cusco) in montane forest and rarely in premontane forest at (700–) 1400–2700 m ( Fig. 38 ). It has been collected in flower from February to December, and in fruit from March to November.

Specimens examined:— PERU. Amazonas: path from Chachapoyas to Moyobamba, 2700–3300 m, Jan 1930 (ster.), L. Williams 7598 ( F!); near the border with Dept. San Martín, 2000 m, 03 Apr 2001 (fl.), H. van der Werff et al. 16639 ( NY!). Prov. Bongará, montane rainforest along Yambrasbamba Trail between Yambrasbamba and Yanayacu, 2200–2300 m, 05°41’S, 77°48’W, 26 Jun 1962 (fl., fr.), J. Wurdack 1050 ( F!, NY!, USM!, US!); Shillac , norte del camino de Pedro Ruíz, 2300 m, 05°49’S, 78°01’W, 31 Aug-02 Sep 1983 (fl.), D. Smith & S. Vásquez 4868 ( USM!); Dist. Shipasbamba, Shilla , 1850–1900 m, 06 May 1981 (fr.), K. Young & M. Eisenberg 381 ( NY!); Dist.Yambrasbamba, alrededores de CP Miraflores, 2100, 05°42’05”S, 77°55’35”W, 03 Jul 2022 (fl., fr.), R. Fernandez-Hilario et al. 2227 ( MOLF!), Buenos Aires , 1860–2000 m, 02–26 Mar 1967 (fl.), S. Tillet 673–310 ( US!, USM!), Centro de Investigación de la ONG Neotropical Primate Conservation y bosque “El Toro”, 2000 m, 05°39’17.05”S, 77°54’51.30”W, 22–28 Jul 2018 (fr.), R. Fernandez-Hilario et al. 1431 ( MOLF!), ruta desde CP Santa Rosa hacia bosque El Toro, 2160 m, 05°40’41.13”S, 77°55’12.72”W, 11 Nov 2020 (fl. bud), R. Fernandez-Hilario et al. 2057 ( HOXA!, MOLF!, NY!, UPCB!). Prov. Luya, Dist. Camporedondo, Tullanya , 1700–2000 m, 06°09’07”S, 78°21’05”W, 27 Nov 1996 (fl.), R. Vásquez et al. 211859 ( HUT!, MOLF!, USM!). Ayacucho: Prov. La Mar, Machete , 1100 m, 26 Oct 2000 (ster.), L. Vargas 03 ( USM!). Cajamarca: Prov. Jaén, Dist. Chirinos , Las Pírias, 14 Jul 2005 (fr.), J. L. Marcelo-Peña & A. Castillo 1709 ( MOLF!); Dist. Jaén, San José de la Alianza y Nueva Jerusalén, 25 May 2012 (fl.), L. Dávila 2409 ( UNC!). Prov. San Ignacio , camino arriba de Nuevo Trujillo cerca de Santa Fé, 1182–1600 m, 05°01’09”S, 78°52’11”W, 16 Mar 2012 (fl.), F. A. Michelangeli et al. 1756 ( NY!); Dist. Huarango, Poblado Selva Andina , trocha comunal, 1613 m, 05°03’02”S, 78°45’14”W, 25 Apr 2007 (fl., fr.), J. Perea & J. Mateo 3085 ( NY!), Poblado Selva Andina , trocha de captación de agua, 1798 m, 05°03’37”S, 78°45’13”W, 18 Apr 2007 (fl.), J. Perea & J. Mateo 2969 ( NY!); Dist. San José de Lourdes , 1650 m, 05°00’43”S, 78°54’09”W, 14 Feb 2000 (fl. bud), J. Campos & R. Vásquez 6382 ( MOLF!, NY!, USM!), alrededores de Camaná, 1850 m, 05°01’00”S, 78°54’00”W, 22 Mar 1997 (fl., fr.), J. Campos & S. Corrales 3608 ( MOLF!, NY!, USM!), localidad Estrella del Oriente , 1600–1700 m, 04°57’00”S, 78°59’00”W, 04 Sep 1997 (fr.), J. Campos & P. Díaz 4386 ( HUT!, MOLF!, NY!, USM!). Prov. San Ignacio , 12.67 km SW de San Ignacio, 2.88 km de Alto Ihuamaca, 2151 m, 05°12’48.1”S, 79°05’44.9”W, 07 Jun 2011 (ster.), M. Samain et al. 2011- 131 ( USM!). Cusco: Prov. La Convención, Dist. Echarati, Llactahuaman , 1650 m, 12°51’55”S, 73°30’40”W, 14 Jul 1998 (ster.), S. Baldeón et al. 3069 ( USM!), San Antonio, pie de carretera, 1744 m, 12°25’S, 72°32’W, 23 Aug 2005 (fl.), G. Calatayud et al. 3470 ( NY!). Prov. Paucartambo, Kosñipata, San Pedro , 900 m, 13°05’S, 71°10’W, 28 Mar 1991 (fr.), P. Núñez & N. Alanya 13322 ( CUZ!, NY!, USM!), Santa Isabel - San Pedro, 1250 m, 25 Nov 1965 (fl.), C. Vargas 16965 ( CUZ!), same locality and date (fl.), 16995 ( US!); Dist. Kosñipata, road from Pillawata to Patria , 1190 m, 05 Feb 1975 (fl.), T. Plowman & W. Davis 4995 ( US!). Huánuco: Prov. Leoncio Prado, Dist. Pucayacu , PN Cordillera Azul, 1604 m, 08°29’24.42”S, 76°06’14.48”W, 26 Feb 2022 (fr.), R. Rojas et al. 11171 ( HOXA!). Prov. Puerto Inca , Dist. Yuyapichis, CCNN Tahuantinsuyo, Reserva Comunal El Sira, 1568 m, 09°25’20.1”S, 74°44’05”W, 02 May 2014 (fl.), L. Valenzuela et al. 27578 ( HOXA!). Junín: Prov. Satipo, Dist. Llaylla , 1430 m, Feb 2005 (ster.), E. Castro 35 ( MOLF!), Donato , 1635 m, 11°27’39”S; 74°38’07”W, 25 Oct 2019 (fl., fr.), I. Revilla 3484 ( HSP!). Pasco: Prov. Oxapampa, Dist. Huancabamba, PN Yanachaga Chemillén , parte alta de la trocha Tunqui-Cajonpata , 1940 m, 10°16’21”S, 75°30’26”W, 02 Nov 2007 (fl., fr.), A. Monteagudo et al. 15855 ( HOXA!, MOLF!, NY!, USM!); Dist. Palcazú, Alto Lagarto , 700 m, 10°11’57”S, 75°21’23”W, 03 Dec 2007 (fl.), R. Rojas et al. 4817 ( HOXA!, USM!), Palcazú, 2100 m, 10°32’S, 73°23’W, 28 Sep 1984 (fr.), D. Smith 8556 ( US!, USM!). Piura: Prov. Huancabamba, Dist. El Carmen de la Frontera, Rosario bajo, entre el Tambo y Pan de Azúcar , 1935–2250 m, 04°56’23.99”S, 79°18’57.45”W, 25 Apr 2006 (fl.), A. Cano et al. 16342 ( USM!). Ucayali: Prov. Coronel Portillo, Dist. Iparia, falda al cerro Aríapo , Reserva Comunal El Sira , 1800 m, 09°28’16”S, 74°34’54”W, 23 Sep 2011 (fl.), J. Graham 6143 ( MOLF!, NY!) .

Figures

FIGURE 36. Meriania neillii. A. Terminal fertile branch with infructescence. B. Leaf blade, abaxial view. C. Detail of the abaxial leaf surface. D. Longitudinal section of the flower with petals, stamens and style removed. E. Flower bud. F. Petal. G. Stamen, lateral view, with details of dorsal appendages. A–C from J. L. Marcelo-Peña & A. Castillo 1709; D–G from I. Revilla 3484.

FIGURE 37. Meriania neillii. A. Leaf blade, abaxial view. B. Infructescence. C. Terminal fertile branch with inflorescence. D. Flower at anthesis, apical view.A and B from R. Fernandez-Hilario et al. 2227; C from I. Revilla 3484; D from F.A. Michelangeli et al. 1756. Photos by Robin Fernandez-Hilario (A and B), Italo Revilla (C) and Fabián A. Michelangeli (D).

FIGURE 38. Distribution map of M. neillii and M. tomentosa.