1. Myrtaceae Juss.

    1. This family is accepted.

[NTK]

Lucas, E. & Jennings, L. (2009). Neotropical Myrtaceae.

Morphology
Description

Trees or woody shrubs; hairs simple or occasionally dibrachiate. Leaves opposite or sometimes sub-opposite Inflorescences very variable, can be terminal or usually axillary , solitary, dichasial, racemose, glomerulous or sometimes paniculate; perianth free in 4 to 5 parts or calyx calyptrate; stamens free , numerous; anthers versatile, dehiscing by longitudinal slits. Ovary generally inferior, occasionally semi-inferior, mostly 2, 3 or 4 (-10) locular; placentas axile , ovules radiating, sometimes pendulous; vascular supply to ovary trans-septal. Fruit indehiscent , fleshy ; seeds usually numerous; embryo variable with cotyledons small and straight or elongate and curved, well developed and leafy or homogenous.

Distribution
Distribution in the Neotropics
  • Acca O. Berg: Brazil to Peru and Uruguay.
  • Accara Landrum: Brazil.
  • Amomyrtella Kausel: Bolivia and Northern Argentina.
  • Amomyrtus (Burret) Legrand & Kausel: Chile, just into W. Argentina.
  • Blepharocalyx O. Berg: Brazil, Bolivia and Paraguay, Chile and Argentina.
  • Calycolpus O. Berg: Panama and Colombia, Venezuela to Peru and Trinidad, Guyana and Northern Brazil.
  • Calycorectes O. Berg: Cuba, Mexico south to Northern Argentina.
  • Calyptranthes Sw.: Florida and Caribbean, Mexico south to Northern Argentina.
  • Campomanesia Ruíz & Pavón: Brazil north to Venezuela and Trinidad, west to Colombia and Peru and south to Northern Argentina.
  • Chamguava Landrum: Mexico (Guerrero, Chiapas) to Honduras and Panama.
  • Eugenia L. Pantropical - in the Neotropics: Southern Florida and Caribbean and from Mexico to Argentina.
  • Gomidesia O. Berg: Brazil north to Venezuela, Guyana and the Caribbean to Hispaniola, south into Paraguay and Argentina.
  • Hexachlamys O. Berg: Southern Brazil and Paraguay to Bolivia and Northern Argentina.
  • Legrandia Kausel: Chile.
  • Luma A. Gray: Peru: Chile and Argentina.
  • Marlierea Cambess.: Trinidad-Tobago and Windward Is., Costa Rica to Colombia, Venezuela and the Guianas and Northern Brazil.
  • Mosiera Small: Southern Florida and Caribbean.
  • Myrceugenia O. Berg: Brazil to Argentina, Chile and Juan Fernandez Is.
  • Myrcia DC. ex Guillemin: Mexico and Caribbean south to Argentina.
  • Myrcianthes O. Berg: Florida and Caribbean, Mexico south to Chile, Argentina and Uruguay.
  • Myrciaria O. Berg: Guatemala and Belize south to Paraguay and Northern Argentina.
  • Myrrhinium Schott: Ecuador and Peru to Southern Brazil and Northern Argentina.
  • Myrteola O. Berg: From the Andes of Colombia south to Tierra del Fuego and Falkland Is.
  • Neomitranthes Legrand: SE. and Southern Brazil.
  • Pimenta Lindl.: Caribbean from Cuba to Trinidad, Mexico (Veracruz, Oaxaca) to Panama, Southern Bolivia, Southern and SE. Brazil.
  • Plinia L.: Caribbean: Costa Rica south through tropical South America to Argentina.
  • Psidium L.: Southern Mexico and Caribbean through tropical South America to Northern Argentina.
  • Siphoneugena O. Berg: Brazil north to Venezuela, the Guianas and Caribbean to Puerto Rico, south into Argentina.
  • Tepualia Griseb.: Chile.
  • Ugni Turcz.: Guatemala to Guyana (Mt. Roraima) and Chile, Juan Fernandez Is.
Diagnostic
Useful tips for generic identification
  • Observe texture of seed testa.
  • Observe embryo shape and size.
  • Observe number of perianth parts.
  • Observe inflorescence architecture.
  • Note collection locality.
Notable genera and distinguishing features
  • Blepharocalyx: seed testa soft, embryo c-shaped, perianth 4-merous, parts free, arranged in a distinctive square upon ovary; inflorescences in complex branching dichasia of up to 35 flowers; single very variable and widely distributed species in Brazil, Venezuela and tropical Argentina.
  • Eugenia: seed testa soft; embryo homogenous resembling a bean; perianth mostly 4-merous, parts free, flowers often subtended by evident, conspicuous bracts; inflorescences solitary, in fascicles, spikes or racemes; widely distributed throughout the Neotropics, > 1,000 species.
  • Myrcia s.l.: seed testa soft; embryo membranous, plicate with long, distinct hypocotyl; perianth mostly 5-merous, calyx lobes free or fused, tearing open irregularly or circumscissile and falling as a calyptra; inflorescences in panicles; widely distributed throughout the Neotropics, > 700 species.
  • Myrceugenia: seed testa soft; embryo membranous, plicate with long, distinct hypocotyl; perianth mostly 4-merous, parts free (rarely circumscissile), valvate; inflorescences solitary or in dichasia; common in Brazil to Argentina: Chile and the Juan Fernandez Islands.
  • Pimenta: seed testa hard in all but one species, embryo c-shaped, perianth (4-)5-merous, parts free; inflorescences in complex branching dichasia of many flowers; extremely aromatic plant; common in central America, the Caribbean and southern Brazil.
  • Psidium: seed testa hard, embryo c-shaped, perianth mostly 4-merous, parts free to fused often tearing open irregualarly; inflorescences solitary or in panicles; common throughout South America.
  • Myrciaria, Neomitranthes, Plinia and Siphoneugena: seed testa soft; embryo homogenous resembling a bean; perianth mostly 4-merous, parts free or fused and falling as a circumscissile but open ring or tearing irregularly; inflorescences mostly sessile and in glomerules; central America, the Caribbean and particularly common in southern Brazil.
Distinguishing characters (always present)
  • No characters are ALWAYS present.
Other important characters
  • Opposite, simple leaves.
  • Pellucidgland dots on leaves and often other parts.
  • Leaves aromatic when crushed.
  • Intramarginal collecting vein present.
  • Inferior ovary.
  • No evident stipules.
  • Many (>100) stamens.
Key differences from similar families

The families listed below differ from Myrtaceae in the following characters:

  • Clusiaceae: plants usually with latex; leaves sometimes with dark resin-filled dots; flowers often unisexual; ovarysuperior.
  • Malpighiaceae: leaves without translucent dots, an interpetiolar scar often present; flowers with clawed petals, few stamens; calyx with prominentglands at the base on the outer surface.
  • Oleaceae: leaves sometimes serrate; no part of plant bearing pellucidgland dots; stamens 2; ovarysuperior.
  • Melastomataceae (especially Mouriri): plants without translucent dots; no part of plant bearing pellucidgland dots; stamens <20, anthers sickle shaped and isomerous; inflorescences often cymose.
  • Rubiaceae (especially in fruit): plants without translucent dots; interpetiolar stipules distinct in most specimens; corolla tubular; stamens 4-5.
  • Rutaceae (species with simple leaves): leaves alternate; flowers with few stamens; prominent intrastaminal nectary-disc; ovarysuperior.
General Description
Status
  • All genera listed are native, and all but Eugenia are endemic to the Neotropics. 
  • Psidium (Guava), Eugeniauniflora (Pitanga) and Myrciariacauliflora (Jaboticaba) are widely cultivated for fruit, jams and juices.
  • Syzygiumjambos and various Eucalyptus species are introduced, cultivated (for fruit and timber/shade respectively) and are often naturalized.
Number of genera
  • 29 genera: Acca, Accara, Amomyrtella, Amomyrtus, Blepharocalyx, Calycolpus, Calycorectes, Calyptranthes, Campomanesia, Chamguava, Eugenia, Hexachlamys, Legrandia, Luma, Marlierea, Mosiera, Myrceugenia, Myrcia, Myrcianthes, Myrciaria, Myrrhinium, Myrteola, Neomitranthes, Pimenta, Plinia, Psidium, Siphoneugena, Tepualia, Ugni.
Literature
Important literature

Govaerts, R., Sobral, M., Ashton, P., Barrie, F., Holst, B.K., Landrum, L.L., Matsumoto, K., Mazine, F.F., Nic Lughadha, E., Proença, C., Soares-Silva, L.H., Wilson, P.G. and Lucas, E. 2008. World Checklist of Myrtaceae. Kew Publishing: Royal Botanic Gardens, Kew.

Landrum, L.R. and Kawasaki, M.L. 1997. The genera of Myrtaceae in Brazil: an illustrated synoptic treatment and identification keys. Brittonia. 49: 508-536.

Lucas, E.J., Harris, S.A., Mazine, F.F., Belsham, S.R., Nic Lughadha, E.M., Telford, A., Gasson, P.E. and Chase, M.W. 2007. Suprageneric phylogenetics of Myrteae, the generically richest tribe in Myrtaceae (Myrtales). Taxon 56: 1105-1128.

McVaugh, R. 1956. Tropical American Myrtaceae, notes on generic concepts and descriptions of previously unrecognized species. Fieldiana, Bot. 29: 145-228.

McVaugh, R. 1963. Tropical American Myrtaceae, II, notes on generic concepts and descriptions of previously unrecognized species. Fieldiana 29: 393-532.

McVaugh, R. 1968. The genera of American Myrtaceae - an interim report. Taxon 17: 354-418.

[FWTA]

Myrtaceae, Hutchinson and Dalziel. Flora of West Tropical Africa 1:1. 1954

Habit
Trees or shrubs
Leaves
Leaves simple, mostly entire, opposite or rarely alternate, glandular-punctate; stipules 0 or rarely very small
Flowers
Flowers mostly actinomorphic, hermaphrodite or polygamous by abortion
Calyx
Calyx-tube more or less adnate to the ovary; lobes 3 or more, imbricate or valvate or irregularly split
Corolla
Petals 4–5, rarely 6 or 0, inserted on the margin of the disk lining the calyx-tube, imbricate or connivent in a mass
Androecium
Stamens numerous, rarely few, inserted on the margin of the disk, 1- or more-seriate, indexed in bud or twice folded or straight; filaments free or connate at the base into a short tube or in bundles opposite the petals; anthers small, 2-celled, opening lengthwise by slits or rarely by apical pores, the connective often tipped by a gland
Gynoecium
Ovary inferior, syncarpous, 1- to many-celled, with mostly axile, rarely parietal placentas; ovules rarely solitary or few
Fruits
Fruit inferior, loculicidally dehiscent or indehiscent
Seeds
Seeds with no (or very little) endosperm; embryo straight, incurved, circular or spiral
[FZ]

Myrtaceae, F. White. Flora Zambesiaca 4. 1978

Habit
Trees, shrubs or rhizomatous, geoxylic suffrutices
Leaves
Leaves usually opposite or subopposite, rarely alternate, ternate, or in fours, simple, entire, often coriaceous, pellucid-punctate
Stipules
Stipules absent
Inflorescences
Inflorescence axillary or terminal, paniculate, thyrsoid, umbellate, cymose, racemose, or flowers solitary or fasciculate
Flowers
Flowers mostly bisexual, sometimes unisexual by abortion, actinomorphic, partly or completely epigynous
Calyx
Sepals (0)4–5, often persistent, rarely accrescent, sometimes fused to form an operculum, often with punctate glands
Corolla
Petals (0)4–5, imbricate, free or coherent to form a calyptra or fused to form an operculum, often with punctate glands
Androecium
Stamens usually numerous, free or basally connate; filaments often coiled or folded in the bud; anthers basifixed or dorsifixed, connective sometimes with an apical gland
Gynoecium
Ovary inferior or half-inferior, with (1)2–5(10) locules; septa sometimes incomplete; placentation axile or parietal and then often with deeply intruded placentae; ovules 1 to numerous per locule or placenta; style 1, punctiform, capitate, funnel-shaped or shallowly 2–3-lobed at the apex
Fruits
Fruit a berry, drupe or loculicidal capsule which only dehisces near the apex, rarely nut-like and indehiscent
Seeds
Seeds 1 to many per locule; endosperm absent or scanty; embryo straight or incurved
[FTEA]

Myrtaceae, B. Verdcourt, B.Sc., Ph.D.. Flora of Tropical East Africa. 2001

Habit
Trees, shrubs or occasionally pyrophytic subshrubs with massive rootstocks; usually evergreen; pith with internal phloem
Leaves
Leaves simple, predominantly opposite, often coriaceous, mostly entire, glandular-punctate; stipules absent or very reduced
Flowers
Flowers mostly regular, hermaphrodite or unisexual, solitary or in simple to complex inflorescences; bracteoles often present
Hypanthium
Hypanthium (“calyx-tube”) ± adnate to the ovary; lobes 3–6(–10), imbricate, valvate, splitting irregularly or forming an operculum
Corolla
Petals 4–5(–6) or rarely absent, included on the margin of the disc lining the calyx-tube, imbricate or forming an operculum
Androecium
Stamens numerous, rarely only 4, 5 or 10, included on the disc margin in 1 or more rows, straight, inflexed or twice folded in bud; filaments free or connate at the base into a short tube or in 4–5 bundles opposite the petals; anthers small, 2-locular, opening by slits or less often by apical pores; connective sometimes tipped by a gland
Gynoecium
Ovary inferior or ± superior, (1–)2–5(–16)-locular with axile or rarely parietal placentation; ovules (1–)2–many, anatropous to campylotropous; style terminal (absent in one genus)
Fruits
Fruit a berry or capsule (less often a drupe or nut), (1–)few(–many)-seeded, indehiscent or loculicidally dehiscent
Seeds
Seeds without or with very little endosperm; embryo straight, incurved, circular or spiral
[FZ]

Heteropyxidaceae, A. Fernandes. Flora Zambesiaca 4. 1978

Habit
Aromatic trees or shrubs
Leaves
Leaves alternate, simple, attenuate into a ± long petiole, pellucid-punctate
Flowers
Flowers dioecious by abortion, actinomorphic, yellowish, sweet-scented Female flowers: perianth as in male; staminodes (4)5–8, minute; ovary free, superior, 2(3)-locular, gland-dotted, with ¥ ovules inserted on an axile placenta; style inserted in a depression of the ovary apex, cylindric, glabrous or pilose, with a large, papillose and capitate stigma Male flowers: receptacle cyathiform, with (4)5 imbricate segments; petals 4(5), perigynous, free, imbricate, gland-dotted; stamens (4)5–8(9–10), perigynous, free, exserted, (4)5 opposite to the petals, the others to the receptacle segments, filaments straight; anthers dorsifixed, dehiscing longitudinally, with 1–3 glands on the back of the connective; disk perigynous, lining the lower 1/2 of the resceptacle, glabrous or ± pilose; pistillode turbinate, with a sessile or short style and a papillose stigma
Male
Male flowers: receptacle cyathiform, with (4)5 imbricate segments; petals 4(5), perigynous, free, imbricate, gland-dotted; stamens (4)5–8(9–10), perigynous, free, exserted, (4)5 opposite to the petals, the others to the receptacle segments, filaments straight; anthers dorsifixed, dehiscing longitudinally, with 1–3 glands on the back of the connective; disk perigynous, lining the lower 1/2 of the resceptacle, glabrous or ± pilose; pistillode turbinate, with a sessile or short style and a papillose stigma
Female
Female flowers: perianth as in male; staminodes (4)5–8, minute; ovary free, superior, 2(3)-locular, gland-dotted, with ¥ ovules inserted on an axile placenta; style inserted in a depression of the ovary apex, cylindric, glabrous or pilose, with a large, papillose and capitate stigma
Fruits
Fruit a small loculicidal 2(3)-valved capsule
Seeds
Seeds ± straight, the outer ones winged at the extremities, without endosperm

Images

Myrtaceae Juss. appears in other Kew resources:

First published in Gen. Pl. [Jussieu] 322. 1789 [4 Aug 1789] (1789)

Accepted by

  • APG IV (2016) http://dx.doi.org/10.1111/boj.12385

Sources

Flora Zambesiaca
Flora Zambesiaca
http://creativecommons.org/licenses/by-nc-sa/3.0

Flora of Tropical East Africa
Flora of Tropical East Africa
http://creativecommons.org/licenses/by-nc-sa/3.0

Flora of West Tropical Africa
Flora of West Tropical Africa
http://creativecommons.org/licenses/by-nc-sa/3.0

Kew Names and Taxonomic Backbone
The International Plant Names Index and World Checklist of Selected Plant Families 2018. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
© Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

Neotropikey
Milliken, W., Klitgard, B. and Baracat, A. (2009 onwards), Neotropikey - Interactive key and information resources for flowering plants of the Neotropics.
http://creativecommons.org/licenses/by/3.0