Alfaroa

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Eudicots
Cladus: Core eudicots
Cladus: Rosids
Cladus: Eurosids I
Ordo: Fagales

Familia: Juglandaceae
Subfamilia: Engelhardioideae
Genus: Alfaroa
Species: A. costaricensis – A. guanacastensis – A. guatemalensis – A. hondurensis – A. manningii – A. mexicana – A. williamsii
Name

Alfaroa Standl., J. Wash. Acad. Sci. 17(4): 78. (1927)

Alfaroa costaricensis Standl. J. Wash. Acad. Sci. 17(4): 78. 1927

References

Standley, P. C. 1927. Alfaroa, a new genus of trees of the family Juglandaceae from Costa Rica. Journal of the Washington Academy of Sciences 17 (4): 77-79. BHL Reference page.
International Plant Names Index. 2015. Alfaroa. Published online. Accessed: Jan. 26 2015.
Hassler, M. 2018. Alfaroa. World Plants: Synonymic Checklists of the Vascular Plants of the World In: Roskovh, Y., Abucay, L., Orrell, T., Nicolson, D., Bailly, N., Kirk, P., Bourgoin, T., DeWalt, R.E., Decock, W., De Wever, A., Nieukerken, E. van, Zarucchi, J. & Penev, L., eds. 2018. Species 2000 & ITIS Catalogue of Life. Published on the internet. Accessed: 2018 Feb. 02. Reference page.
Stone, D.E. 2010. Review of New World Alfaroa and Old World Alfaropsis (Juglandaceae). Novon 20(2): 215–224. DOI: 10.3417/2009027 BHL Reference page.
Tropicos.org 2015. Alfaroa. Missouri Botanical Garden. Published on the internet. Accessed: 2015 Jan. 24.

Alfaroa is a genus of evergreen trees in the Juglandaceae family of the Fagales, growing in montaine and submontaine tropical rain forests in Central America. The wood is characterized by solid pith, pink heartwood, and vessels with scalariform perforations, as well as simple perforations.
Description

The (usually pinnately compound) leaves are evergreen and lack stipules. They are alternate, rarely opposite.

The plants are monoecious, the male flowers being in lateral panicles (several pairs of catkins on an inflorescence) and the female flowers born terminally either in a single spike or in a hermaphroditic panicle including several paired male catkins. Each flower has a wide bract, two bracteoles, and four sepals. The flowers are sessile. The male flowers have a round or oblong receptacle and six to ten stamens. The pollen grains are approximately 24 micrometers in diameter and are slightly triangular in polar view.

The small fruits are nuts, one-chambered at the apex and eight-chambered (sometimes four-chambered) at the base. Germination is hypogeal.
Species

Alfaroa includes the following species (This list may be incomplete):

A. columbiana, G. Lozano-C., J. Hernandez-C., & S. Espinal-T.
A. costaricensis, Standl. —Campano Chile, Chiciscua, Gaulin, Gavilancillo
A. guanacastensis, D. E. Stone
A. guatemalensis, (Standl.) L. O. Williams & A. Molina 1970
A. hondurensis, L.O. Williams 1959
A. manningii, Jorge Leon
A. mexicana, D. E. Stone
A. roxburghiana (Wall.) I. A. Iljinsk.
A. williamsii, A. Modina R.

A. guatemalensis and A. roxburghiana were originally described as belonging to the genus Engelhardia. The monotypic genus Alfaropsis I. A. Iljinsk has also been erected for A. roxburghiana.
References

Elliott, L. L., Mindell, R. A., & Stockey, R. A., "Beardia vancouverensis Gen. et Sp. Nov. (Juglandaceae): Permineralized Fruits from the Eocene of British Columbia", American Journal of Botany 93(4): 557–565, 2006

Manchester, Steven R., "Fossil Wood of the Engelhardieae (Junglandaceae) from the Eocene of North America: Engelhardioxylon Gen. Nov.", Bot. Gasz 144(1)157-163, 1983.

J. A. Vozzo (ed.) Tropical Tree Seed Manual "Part II—Species Descriptions", USDA Forest Service