Simaroubaceae Explained

The Simaroubaceae are a small, mostly tropical, family in the order Sapindales. In recent decades, it has been subject to much taxonomic debate, with several small families being split off. A molecular phylogeny of the family was published in 2007, greatly clarifying relationships within the family.^[1] Together with chemical characteristics such as the occurrence of petroselinic acid in Picrasma,^[2] in contrast to other members of the family such as Ailanthus,^[3] this indicates the existence of a subgroup in the family with Picrasma, Holacantha, and Castela.

The best-known species is the temperate Chinese tree-of-heaven Ailanthus altissima, which has become a cosmopolitan weed tree of urban areas^[4] and wildlands.^[5]

Well-known genera in the family include the tropical Quassia and Simarouba.

Genera

20 genera are accepted:^[6]

• Ailanthus
• †Ailanthophyllum
• Brucea
• Castela
• Eurycoma
• Gymnostemon
• Hannoa
• Homalolepis
• Iridosma
• Leitneria
• Nothospondias
• Odyendea
• Perriera
• Picrasma
• Picrolemma
• Pierreodendron
• Quassia
• Samadera
• Simaba
• Simarouba
• Soulamea ^[7]

Excluded genera

• Allantospermum → Ixonanthaceae
• Alvaradoa → Picramniaceae
• Desbordesia → Irvingiaceae
• Harrisonia → Rutaceae
• Irvingia → Irvingiaceae
• Kirkia → Kirkiaceae
• Klainedoxa → Irvingiaceae
• Picramnia → Picramniaceae
• Recchia → Surianaceae^[8]

Notes and References

1. Joshua W. . Clayton . Edwino S. Fernando . Pamela S. Soltis . Pamela S. Soltis . Douglas E. Soltis . Douglas E. Soltis . 2007 . Molecular phylogeny of the tree-of-heaven family (Simaroubaceae) based on chloroplast and nuclear markers . International Journal of Plant Sciences . 168 . 9 . 1325–1339 . 10.1086/521796. 86016778 .
2. Tsujimoto, M. . Koyanagi, H. . 1933. Bull. Chem. Soc. Jpn. On Nikagi Oil. 8. 5. May 1933. 161-167.
3. T. Stuhlfauth. H. Fock. H. Huber. K. Klug. The distribution of fatty acids including petroselinic and tariric acids in the fruit and seed oils of the Pittosporaceae, Araliaceae, Umbelliferae, Simarubaceae and Rutaceae. Biochemical Systematics and Ecology. 13. 1985. 447–453 . 10.1016/0305-1978(85)90091-2.
4. Elizabeth Pan. Nina Bassuk. Establishment and Distribution of Ailanthus altissima in the Urban Environment. J. Environ. Hort.. 4. 1. 1-4. March 1986.
5. 3088649. Invasion of an Old-Growth Forest in New York by Ailanthus altissima: Sapling Growth and Recruitment in Canopy Gaps. Journal of the Torrey Botanical Society. 127. 4. 307. Knapp. Liza B. Canham. Charles D. 10.2307/3088649. 2000.
6. Web site: Simaroubaceae DC . Plants of the World Online . 16 December 2023.
7. Web site: GRIN Genera of Simaroubaceae. Germplasm Resources Information Network . United States Department of Agriculture . 2011-04-19.
8. Web site: GRIN genera sometimes placed in Simaroubaceae . Germplasm Resources Information Network . United States Department of Agriculture . 2011-04-19.