Marlierea summa var. superior McVaugh (1958: 91) Marlierea summa var. calva McVaugh (1969: 69) Marlierea vicina McVaugh (1969: 70) A taxonomic monograph of Myrcia sect. Sympodiomyrcia (Myrteae, Myrtaceae) Santos, Matheus F. Lucas, Eve Sano, Paulo T. Phytotaxa 2018 2018-12-05 380 1 448 450 73S4H (McVaugh 1958: 89) M. F. Santos (2016 b: 29) M. F. Santos 29 2016 McVaugh 89 1958 [178,864,158,185] Magnoliopsida Myrtaceae Myrcia Plantae Myrtales 91 Tracheophyta species summa   ≡  Marlierea summa McVaugh. Type:— VENEZUELA. Amazonas: Cerro Sipapo(Paráque),  26–28 January 1949(fl.), Maguire 28644( holotypeMICH!, isotypesNY!, S!, US! VEN [image!])   =   Marlierea summa var. superior McVaugh (1958: 91). Type:— VENEZUELA. Ilu-Tepui, Gran Sabana,  14 March 1952(fl.),  Maguire33405( holotypeMICH!, isotypeNY!)  =   Marlierea summavar. calva McVaugh (1969: 69). Type:— VENEZUELA. Bolívar: Chimantá Massif, 5 February 1955(fl.), Steyermark 493( holotypeMICH!, isotypesF!, NY [two sheets]!, S!, US!)  =   Marlierea vicina  McVaugh (1969: 70). Type:— GUYANA. Upper Mazaruni River Basin. Mt. Ayanganna,  7 August 1960(fl.), Tillett 45172( holotypeMICH!, isotypesCOL [image!], F!, NY!, S!, US!, VEN [image!])  Shrubto tree 1–15 mhigh. Epidermal peeling absent in immature parts (rarely present); trichomes ferruginous, brown, light brown to white, 0.1–0.3 mmlong. Twigwhen immature brownish or straw-like (when dry), flattened, sulcate, not keeled, tomentose, minutely tomentose, pubescent, puberulent or with scattered trichomes; mature twig greyish or brownish (when dry), cylindrical, cortex slightly cracked, glabrescent to glabrous; branching mainly sympodial (rarely monopodial), 2–6 branches per node, epidermal protrusion present at the nodes, internode 2.0– 10.5 cmlong; cataphyll scale-like, 1 mmlong, present in all internodes, early deciduous, free, ovate, externally pubescent; terminal node with central and lateral buds developed or lateral ones undeveloped, tomentose, pubescent or puberulent. Leafdiscolorous, chartaceous or coriaceous, blade 2.4–17.0 × 0.5–8.0 cm, narrowly elliptic, elliptic, oblong, lanceolate to widely ovate or obovate, apex caudate or acuminate to rounded, base attenuate or narrowly cuneate to obtuse, margin plane to slightly revolute, secondary veins 2–7 mmapart, held at an angle of 50–90° relative to the midvein, one or two marginal veins, the first 1–2 mmand the second 1 mmfrom the margin, tertiary veins conspicuous to inconspicuous; adaxial surface tomentose, minutely tomentose, puberulent or with scattered trichomes to glabrous when immature, glabrescent to glabrous at maturity, midvein sulcate to flat in the first half and flat in the second half, secondary veins inconspicuous (sometimes raised), pellucid dots conspicuous to inconspicuous, less than 5 to more than 15 per mm 2; abaxial surface tomentose, minutely tomentose, pubescent, puberulent or with scattered trichomes when immature, tomentose, pubescent, puberulent or glabrescent to glabrous at maturity, midvein raised, secondary veins raised or inconspicuous, pellucid dots conspicuous to inconspicuous, less than 5 to more than 15 per mm 2; petiole 3–17 × 1–2 mm, canaliculate, tomentose, minutely tomentose, pubescent, puberulent or with scattered trichomes when immature, pubescent, puberulent or glabrescent to glabrous at maturity. Inflorescence1.5–7.5 × 1.5–8.5 cm, pyramidal, axillar at the terminal node, terminal dichasia usually with three flowers, 1–50 flowers, rachis tomentose, minutely tomentose, pubescent, puberulent or with scattered trichomes, 1–12 branching at the base, first internode of central rachis 1–2 mmwide, cylindrical to flattened, distal internodes flattened, opposite branching (rarely subopposite), 2–4 branching per node, epidermal protrusion present at the nodes (usually absent in the apical branches). Bract1–5 × 1 mm, deciduous, lanceolate or ovate, concave, apex acuminate or acute, base truncate, adaxial surface tomentose, pubescent, puberulent to glabrous, abaxial surface tomentose, pubescent, puberulent or with scattered trichomes. Pedicel 0–2 mmlong, cylindrical, tomentose, pubescent or puberulent. Bracteole1–2 × 0.5–1.0 mm, deciduous, lanceolate or ovate, concave, apex acuminate or acute, base truncate, adaxial surface tomentose, puberulent to glabrous, abaxial surface tomentose or puberulent. Floral bud3–5 × 1–4 mm, turbinate. Hypanthium0.8–2.0 mm extending above the summit of the ovary, not tearing at anthesis (sometimes with a small vertical rupture), externally tomentose, pubescent or puberulent, pellucid dots inconspicuous (usually covered by the indumentum), internally glabrous; calyx 3–5-merous, lobes 0.4–2.4 × 0.8–3.6 mm, distinct from the hypanthium, deciduous, depressed ovate, widely depressed ovate or deltate, concave, apex rounded (rarely acute or obtuse), base truncate, externally tomentose, pubescent, puberulent or with scattered trichomes to glabrous, internally tomentose, minutely tomentose, pubescent or puberulent; corolla 3–6-merous, petals reddish, light brown to white, 0.8–3.2 × 1.0– 3.2 mm, depressed ovate to widely ovate, depressed obovate or very widely obovate, concave, apex rounded, base truncate, externally pubescent, puberulent or with scattered trichomes to glabrous, internally puberulent or with scattered trichomes to glabrous; staminal ring 0.2–0.4 mmwide, glabrous (rarely with scattered trichomes), stamens 67–112, filament 2.2–4.0 mm long, white, glabrous, anther 0.24–0.32 × 0.16–0.48 mm, square, oblong or transversely oblong; ovary 0.8–1.2 × 0.8–1.8 mm, 2-locular, each locule with two ovules, style 4.0– 4.8 mmlong, glabrous, stigma punctiform, papillose. Fruitgreen to yellowish when immature, vinaceous at maturity, 6–11 × 6–11 mm, depressed globose or globose, base rounded, glabrescent to glabrous, remnants of calyx lobes present or not; seeds 1–3.   Distribution and Habitat:—  Myrcia summaoccurs throughout the Guiana Highlands, including south and eastern Venezuela(e.g. Ayuan-Tepuí, ChimantáMassif, Cerro Sipapo, Ilu-Tepuí), western Guyana(e.g.  Cuyuni-Mazaruniand  Potaro-Siparuniregions) and northernmost Brazil(e.g. Pico da Neblina,  Serrado Aracá) ( Figure 12). It is found usually above 1000 melevation, but there are records down to 600 mof elevation. The species inhabits different vegetation types: carrasco, campo rupestre, high montane forest, margin of watercourses and rocky outcrops.  Phenology:—It flowers from January to March and in May, July, August, October and December; flowering is concentrated in January and February. Specimens with fruits were found from October to March and in May, June and August (mature fruits in August, October, December and February).  Conservation Status:—The species has a relatively wide distribution in the Guiana Highlands (Extent of Occurrence ca. 323,100 km 2), including records in many tepuis, which are protected areas; it is also found in more than 10 locations. However, the small Area of Occupancy ( 92 km 2) probably reflects its real distribution because the species occurs mainly in high elevation areas scattered through the region. This conflicting information led us to consider  Myrcia summaas Data Deficient (DD; IUCN 2001).   Discussion:—  Myrcia summahas morphological similarity with  Myrcia mutabilis, sharing inconspicuous venation on the adaxial surface of leaf blade and sympodial branching. It differs from  Myrcia mutabilisin the strongly ferruginous indumentum (versus ochraceous) and the narrower floral bud.  Myrcia summaoften shows a slight split in the hypanthium tissue at anthesis, probably because the floral bud is relatively narrow; other floral features are standard for  Myrciasect. Sympodiomyrcia. The species has great morphological plasticity; this is reflected in the current synonymy:  Marlierea summavar. calva, with big, glabrous leaves;  Marlierea summavar. superior, with leaves with nearly rounded apices (which are usually caudate) and conspicuous and raised venation on both surfaces (rare in the species). Regarding the synonym  Marlierea vicina, specimens from the typelocality have an ochraceous indumentum, chartaceous leaves, thicker inflorescences, longer persistent bracts and bigger floral buds.  Available illustrations and images:— Holst et al.(2003; as  Marlierea summa).  Additional specimens examined:—  BRAZIL.  Amazonas: Mun. Barcelos,  28 January 1978(fr),  N.A.Rosa2264(MG!, MO!); ibidem,  1200–1400 m, 0 °51’0”N, 63 °21’0”W,  19 February 1984(fr), G.T. Prance29174(K!, NY!);  Serrado Aracá,  1150–1250 m, 0 °51’0”N, 63 °22’0”W,  13 February 1984(fr),  A.S.Tavares19(INPA!, NY!); ibidem,  1200 m, 0 °0’0”N, 63 °0’0”W,  13 February 1984(fr), G.T. Prance29040(F!, INPA!, K!, MO!, NY!, RB!, UB!, US!); ibidem,  1150–1250 m, 0 °51’0”N, 63 °22’0”W,  15 February 1984(fr), I.L. Amaral1594(INPA!, K!, MG!, NY!, US!).  GUYANA. Mount Wokomung,  1530 m, 5 °50’0”N, 59 °50’0”W,  14 July 1989(fl), B.M. Boom9232(MO!, NY!); ibidem,  1650 m, 5 °50’0”N, 59 °50’0”W,  7 July 1989(fl), B.M. Boom9125(MO!, NY!).  Cuyuni-Mazaruni,  902 m, 5 °37’3,6”N, 60 °13’8,3”W,  4 December 2002(fr), K.M. Redden1398(K!, US!); ibidem,  1500–2000 m, 5 °17’N, 60 °44’W,  24 February 1989(fr), W. Hahn5449(K!, US!).  Mt. Roraima,  22 October 1973(fl), R. Persaud91(K!). Pakaraima Mountains,  787 m, 5 °35’23,7”N, 60 °13’1, 9”W,  31 January 2004(fr), K.M. Redden1638( US!); ibidem,  1550–1650 m, 5 °4’N, 59 °52’W,  19 November 1993(fr), T.W. Henkel4508( US!); ibidem,  1530 m, 5 °4’N, 59 °62’W,  20 February 1993(fr), T.W. Henkel1519(B!, US!).  VENEZUELA.  Amazonas: Cerro de la Neblina,  1700–1800 m,  10 January 1954(fl),  B.Maguire37223(MICH!, NY!); ibidem,  1600–1800 m,  22 November 1958(fr), B. Maguire42175(MICH!, NY!).  Cerro Sipapo,  1500 m,  10 January 1949(fl),  B.Maguire28262(MICH!, NY!); ibidem,  1500 m,  10 January 1949(fl), B. Maguire28270(F!, K!, MICH!, NY!); ibidem,  1400 m,  15 December 1948(fl), B. Maguire27688(MICH!, NY!); ibidem,  1400 m,  25 December 1984(fl), B. Maguire27906(MICH!, NY!, W!); ibidem,  600 m,  2 February 1949(fr), B. Maguire28719(MICH!, NY!).  Dept. Atabapo,  1500–1600 m, 3 °35’N, 65 °23’W,  11 March 1985(fl),  R.L.Liesner18555( MO!). Dept. Rio Negro, Cerro Aracamuni,  1550 m, 1 °26’N, 65 °47’W,  16 October 1987(fl),  R.L.Liesner22002(BM!, F!, MO!);  Cerro Aracamuni,  1400 m, 1 °32’N, 65 °49’W,  25 October 1987(fl, fr),  R.L.Liesner22419( MO!);  Cerro de la Neblina,  1750–1850 m, 0 °54’N, 66 °4’W,  16–18 February 1984(fl),  R.L.Liesner16101(K!, MO!); ibidem,  1900 m,  16– 17 October 1970(fr), J.A. Steyermark103972(MICH!, US!);  Cerro Sipapo,  1600 m,  8 January 1949(fl),  B.Maguire28257(G!, MICH!, NY!, RB!);  Cerro Sipapo,  1600 m,  8 January 1949(fl),  B.Maguire28237(F!, G!, K!, MICH!, NY!, RB!, S!, US!).  Rio Cuao( Rio Orinoco),  125 m,  3 January 1949(fr), B. Maguire28172(NY!, S!).  Bolívar: Ayan-Tepui,  1800 m, 5 °56’0”N, 62 °34’0”W,  28 August 1983(fr), G.T. Prance28281( NY!).  Cerro Guaiquinima,  1200 m,  2 January 1952(st),  B.Maguire33018( NY!); ibidem,  1680 m, 5 °38’N, 63 °45’W,  30 May 1978(fr), J.A. Steyermark117527( MICH!).  Cerro Jáua,  1922–2100 m, 4 °45’N, 64 °26’W,  22–27 May 1967(fl),  J.A.Steyermark97856(F!, MICH!, MO!); ibidem,  2000 m, 4 °48’50”N, 64 °34’10”W,  27 February 1974(fl), J.A. Steyermark109632(F!, K!, MICH!).  Chimantá Massif,  1880–1995 m,  26 February 1955(fl),  J.A.Steyermark1134(F!, MICH!, NY!, RB!); ibidem, 22000–  2300 m,  20 June 1953(fr), J.A. Steyermark75842(F!, MICH!);  Chimantá Massif( Sarvén-tepuí),  1450 m,  10 January 1953(fl),  J.J.Wurdack34072(G!, IAN!, K!, LE!, M!, MICH!, NY!, W!).  Distrito Piar,  2000 m, 5 °18’N, 62 °9’W,  26–29 January 1983(st),  J.A.Steyermark128001(F!, MO!, US!).  Ilu-Tepui,  1850–1900 m,  11 March 1952(fl),  B.Maguire33378(MICH!, NY!).  Mun. El Dorado,  800–1200 m,  6 March 1962(fr),  J.A.Steyermark44(MICH!, NY!).  Río Cuyuní,  1300–1380 m,  23–24 December 1970(fr), J.A. Steyermark104362( MICH!).   Total: 40 specimens. [339,439,234,255] 1949-01-26 1949-01-28 1949-01-26 Venezuela Cerro Sipapo Type 91 2 Amazonas holotype [337,675,306,327] 1952-03-14 NY Venezuela Maguire Type Gran Sabana 91 2 holotype [327,533,450,471] 1960-08-07 Guyana Type Upper Mazaruni River Basin. Mt. Ayanganna 91 2 holotype 1978-01-28 MO N. A. Rosa Brazil Amazonas Mun. Barcelos 96 1 [300,1446,1058,1085] 1984-02-19 NY Prance Brazil 1300 0.85 21 -63.35 96 1 [136,1353,1094,1121] 1984-02-13 NY A. S. Tavares Brazil 1200 0.85 Araca 21 -63.366665 96 1 1984-02-13 INPA Prance United States of America 1200 0.0 US 21 -63.0 96 1 [136,1447,1166,1193] 1984-02-15 Amaral United States of America 1200 0.85 US 21 -63.366665 96 1 [136,1356,1202,1229] 1989-07-14 NY Boom Guyana 1530 5.8333335 Mount Wokomung 21 -59.833332 96 1 1989-07-07 NY Boom Guyana 1650 5.8333335 21 -59.833332 96 1 2002-12-04 Redden United States of America 902 5.6176667 Cuyuni-Mazaruni 1 -60.21897 96 1 Cuyuni-Mazaruni 1989-02-24 Hahn United States of America 1750 5.2833333 US 1305 -60.733334 96 1 1973-10-22 2004-01-31 1973-10-22 Persaud & Redden United States of America 787 5.5899167 Mt. Roraima 1 -60.217194 Pakaraima Mountains 96 1 1993-11-19 Henkel United States of America 1600 5.0666666 US 1305 -59.866665 96 1 1993-02-20 Henkel United States of America 1530 5.0666666 US 96 1 1954-01-10 NY Cerro de la Neblina & B. Maguire Venezuela 1750 Amazonas 96 1 Amazonas [390,1287,1456,1481] 1958-11-22 NY Maguire Venezuela 1700 96 1 Amazonas 1949-01-10 NY B. Maguire Venezuela 1500 Cerro Sipapo 96 1 Amazonas 1949-01-10 NY Maguire Venezuela 1500 96 1 Amazonas [471,1293,1528,1553] 1948-12-15 NY Maguire Venezuela 1400 96 1 Amazonas 1949-02-02 1984-12-25 1949-02-02 NY Maguire Venezuela 1400 96 1 Amazonas [390,1447,1598,1625] 1985-03-11 MO R. L. Liesner Venezuela 1550 3.5833333 Dept. Atabapo 1307 -65.38333 96 1 Amazonas 1987-10-16 MO R. L. Liesner Venezuela 1550 1.4333334 Rio Negro 1308 -65.78333 Cerro Aracamuni 96 1 Amazonas [216,1311,1670,1697] 1987-10-25 MO R. L. Liesner Venezuela 1400 1.5333333 Cerro Aracamuni 1308 -65.816666 96 1 Amazonas 1984-02-16 1984-02-18 1984-02-16 MO R. L. Liesner Venezuela 1800 0.9 Cerro de la Neblina 1308 -66.066666 96 1 Amazonas 1970-10-16 1970-10-17 1970-10-16 Steyermark United States of America 1900 US 96 1 1949-01-08 MICH, RB B. Maguire United States of America 1600 Cerro Sipapo 96 1 1949-01-08 B. Maguire United States of America 1600 Cerro Sipapo 96 1 1949-01-03 1983-08-28 1949-01-03 NY Maguire & Prance United States of America Ayan-Tepui 125 5.9333334 Rio Cuao 21 -62.566666 Bolivar 96 1 1952-01-02 NY B. Maguire United States of America 1200 Cerro Guaiquinima 96 1 1978-05-30 MICH Steyermark United States of America 1680 5.633333 1305 -63.75 96 1 [250,1447,1922,1949] 1967-05-22 1967-05-27 1967-05-22 MICH, MO J. A. Steyermark United States of America 2011 4.75 Cerro Jaua 1306 -64.433334 96 1 [136,1331,1958,1985] 1974-02-27 MICH Steyermark United States of America 2000 4.813889 21 -64.56944 96 1 1955-02-26 MICH, RB J. A. Steyermark United States of America 1938 Chimanta Massif 96 1 1953-06-20 MICH Steyermark United States of America 2300 96 1 1953-01-10 IAN J. J. Wurdack United States of America 1450 Chimanta Massif Sarven-tepui 96 1 1983-01-26 1983-01-29 1983-01-26 J. A. Steyermark United States of America 2000 97 5.3 Distrito Piar 1305 -62.15 96 1 1952-03-11 NY B. Maguire United States of America 1875 Ilu-Tepui 97 1 [320,1298,196,221] 1962-03-06 NY J. A. Steyermark United States of America 1000 Mun. El Dorado 97 1 1970-12-23 1970-12-24 1970-12-23 MICH Steyermark United States of America 1340 Rio Cuyuni 97 1 [1002,1233,232,257] United States of America Total 97 40