Neotropical Ulmaceae

Description

Trees or shrubs, unarmed, andromonoecious or dioecious. Leaves alternate, distichous, simple, margins entire or serrate, venation pinnate, rarely trinerved, cystoliths sometimes present, deciduous or persistent, stipules lateral. Inflorescence axillary, racemose, fasciculate or paniculate. Flowers hermaphrodite or unisexual, little showy, white, yellowish or greenish; perianth 4-5 (-9) lobed; stamens 4-16, opposite to the perianth lobes; anthers longitudinally dehiscent, ovary superior, sessile or stipitate; carpels 2, 1 (-2) locular, locule 1-ovulate, pendulous placentation. Fruit a samara or drupe; seeds with thin testa.

Notes on delimitation

• The Ulmaceae were previously divided into two tribes or subfamilies - The Ulmoideae and Celtidoideae. Data on morphology, cytology, chemistry and molecular evidence indicate, however, that the Ulmaceae and Cannabaceae (Celtidaceae) are distinct families and that the Cannabaceae (Celtidaceae) is closer to the Moraceae, and some other families in the Urticales, than to the Ulmaceae. The positioning of Ampelocera in Ulmaceae is still controversial.

Distribution in the Neotropics

Family of about 7 genera and 40 species, distributed in temperate and tropical regions. In the Neotropics there are 3 genera and about 13 species:

• Ampelocera Klotzsch - Mexico, Central America, Cuba, Hispaniola, Amazon basin, Bolivia to southern Brazil.
• Phyllostylon Capanema ex Benth. - Mexico, Caribbean islands to Paraguay and Argentina, and southern Brazil.
• Ulmus L. - Mexico, Guatemala, El Salvador, Honduras, Panama.

Distinguishing characters (always present)

• Unarmed trees or shrubs.
• Leaves simple, alternate, distichous, with stipules.
• Flowers bisexual or unisexual.
• Fruit samara or drupaceous.

Key differences from similar families

Key differences from Cannabaceae and Moraceae:

• Plants without latex, unarmed (sometimes armed in Cannabaceae, usually with latex in Moraceae).
• Leaves simple, alternate, distichous, sometimes with cystoliths, stipules lateral (leaves simple or compound, alternate or opposite, without cystoliths, stipules lateral in Cannabaceae; Moraceae generally with simple leaf, alternate, rarely opposite, without cystoliths, usually terminal stipule).
• Perianth imbricate at pre-anthesis (imbricate in Cannabaceae, imbricate or valvular in Moraceae).
• Fruit samara or drupaceous (drupe or achene in Cannabaceae and Moraceae, sometimes forming compound fruit (syconium) in the latter).

Number of genera

• Three genera and 13 species in the Neotropics: Ampelocera (9 spp.) Phyllostylon (2 spp.) and Ulmus (2 sp.).

Useful tips for generic identification

Key to genera of the Neotropical Ulmaceae

1. Leaves with entire or serrate margin, secondary veins curved before the margin … 2
1. Leaves with serrate or biserrate margin, at least some secondary veins terminating at the margin … Ulmus

2. Fruit a samara with 2 unequal, falcate wings … Phyllostylon
2. Fruit drupaceous …. Ampelocera

Or

1. Fruit drupaceous … Ampelocera
1. Fruit a samara … 2

2. Samara 1-winged … Ulmus
2. Samara with 2 unequal and falcate wings … Phyllostylon

Status

• Native: Ampelocera, Phyllostylon and Ulmus  (Ulmus mexicana Planch. and U. ismaelis Todzia & Panero).

General notes

• Species of Ampelocera are hardwood and are used in building homes, furniture or dormant, likewise Ulmus mexicana, whose wood is also heavy and durable. The bark of Ampelocera edentula Kuhlm. is astringent, toxic and ulcerative, and it is used by the population of the Pichis valley, Peru, for tattoos.

Important literature

Linares, J.L. 2005. Primer registro de Ulmus ismaelis (Ulmaceae) para Centroamérica. Revista Mexic. de Biodiv. 76 (1): 95-98.

Nee, M. 1984. Ulmaceae. Flora de Vera Cruz. Instituto Nacional de Investigaciones sobre Recursos Bióticos, Vera Cruz. Fascículo 40, p. 34-38.

Sytsma, K.J., Morawetz. J., Pires, J.C., Nepokroff, M., Conti, E., Zjhra, M., Hall, J.C. & Chase, M.W. 2002. Urticalean Rosids: circumscription, Rosid ancestry, and phylogenetics based on rbcL, trnL-F, and ndhF sequences. Amer. J. Bot. 89(9): 1531-1546.

Todzia, C.A. 1989. A revision of Ampelocera (Ulmaceae). Ann. Missouri Bot. Gard. 76: 1087-1102.

Todzia, C.A. 1992. A reevaluation of the genus Phyllostylon (Ulmaceae). SIDA 15(2): 263-270.

Todzia, C.A. & Panero, J.L. 1998. A new species of Ulmus (Ulmaceae) from southern México and a synopsis of the species in Mexico. Brittonia 50 (3): 343-347.

Torres, R.B. & Luca, A.Q. 2005. Ulmaceae. In M.G.L. Wanderley, G.J. Shepherd, T.S. Melhem & A.M. Giulietti (eds.). Flora Fanerogâmica do Estado de São Paulo. Fapesp & Rima, São Paulo. p. 361-369.

Wiegrefe, S.J., Sytsma, K.J. & Guries, R.P. 1998. The Ulmaceae, one family or two? Evidences from chloroplast DNA restriction site mapping. Pl. Syst. and Evol. 210: 249-270.

How to cite

Torres, R.B. (2009). Neotropical Ulmaceae. In: Milliken, W., Klitgård, B. & Baracat, A. (2009 onwards), Neotropikey - Interactive key and information resources for flowering plants of the Neotropics. http://www.kew.org/science/tropamerica/neotropikey/families/Ulmaceae.htm.