Myricaceae



Myrica californica
Native Plants of Montara

Myrica kilimandscharica
Myrica kilimandscharica
The African Pollen Database



Morella cerifera
USDA APMRU

Myricaceae:
Pollen of the common genera of Myricaceae (Comptonia, Morella, and Myrica) are triporate with strongly protruding (aspidate) pores. The small (20-30 µm) grains resemble birch (Betula), hornbeam (Carpinus), and hop-hornbeam (Ostrya), which share those characters; but the the inner walls of Myricaceae pollen are roughened and the pore wall is thickened toward the base of the pore.

Plants:
The "wax-myrtle family" comprises about 4 genera and 50 species of trees or shrubs with typically aromatic and resinous evergreen (occ. deciduous) leaves. The flowers are small and inconspicuous. The fruits are waxy one-seeded berries born at base of leaves, near the tips of branches. The roots of most species harbour nitrogen-fixing bacteria. The family is widespread except for Auastralasia, North Africa, and temperate Eurasia. The aromatic wax of the fruits is used in bayberry candles.

Pollen light micrograph:
The psilate (scabrate) grains can be distinguished by their strogly aspidate pores, and the thickened-and-roughened inner surface of the pores.

Pollen scanning electron micrograph (SEM)
The diagnostic roughness of the inner wall of the pore is not evident, and the sculpturing of the outer wall is variable among species.

Production and Dispersal:
This wind-pollinated species is a heavy producer and its pollen is well dispersed. Common in Holocene pollen samples from eastern North America to the Arctic.

Preservation:
Good preservation, and the distinctive morphology permits the recognition of degraded pollen grains.

Fossil Occurrence:
The family is considered primitive based on its floral morphology, so the grains potentially may be found well into the Cretaceous; however, Myrica-like pollen (Momipites) first becomes abundant in the early Tertiary.

References:
  • Baird, J. R. 1968. A Taxonomic Revision of the Plant Family Myricaceae of North America, North of Mexico. Ph.D. thesis. University of North Carolina.
  • Chevalier, A. 1901. Monographie des Myricacées. Mém. Soc. Sci. Nat. Cherbourg 32: 85-340.
  • Elias, T. S. 1971. The genera of Myricaceae in the southeastern United States. J. Arnold Arbor. 52: 305-318.
  • Sheffy, M. V. 1972. A Study of the Myricaceae from Eocene Sediments of Southeastern North America. Ph.D. thesis. Indiana University.
  • Wilbur, R. L. 1994. The Myricaceae of the United States and Canada: Genera, subgenera, and series. Sida 16(1): 93-107.
  • Youngken, H. W. 1919. The comparative morphology, taxonomy and distribution of the Myricaceae of the eastern United States. Contr. Bot. Lab. Morris Arbor. Univ. Pennsylvania 4: 339-400.

Links
Owen Davis 10/02