Marasmius koae to the substrate. The fruit body has no distinctive taste or odor. The thin-walled spores are somewhat fusoid (spindle-shaped) to elongated ellipsoidal in shape, smooth, hyaline (translucent), and measure 12–14.5 by 4–4.8 μm. The basidia (spore-bearing cells) are club-shaped, four-spored, and clamped, measuring 24–28 by 7–9 μm. The species is endemic to Hawaii, where it has been found growing in dense groups on the rotting wood of koa ("Acacia koa"). Collections have been made only in the Koa/Ohia Montane Wet Forest on Kauaʻi island. Marasmius koae Marasmius koae is a species of agaric fungus in the Marasmiaceae family. Newly described
Acacia koa there are few koa remaining which are both large and straight enough to do so today. In areas where cattle are present, koa regeneration is almost completely suppressed. However, if the cattle are removed, koa are among the few native Hawaiian plants able to germinate in grassland, and can be instrumental in restoring native forest. It is often possible to begin reforestation in a pasture by disk harrowing the soil, as this scarifies seeds in the soil and encourages large numbers of koa to germinate. Experiments at the Hakalau Forest National Wildlife Refuge have shown that ōhia lehua ("Metrosideros polymorpha")