#2218 - Palhinhaea cernua - Staghorn Clubmoss
Despite the fact that I was still ill from COVID, getting out to the Craters of the Moon hydrothermal area really perked me up, because I could see stuff like this. It had me baffled - it resembled enormous, stiff moss, and I couldn't think what it might be. Turns out they were the first examples of an entire Class of organisms I've ever seen - the Lycopods. And I was going to see a fair few more before I headed back to Australia.
AKA Lycopodiella cernua, Lycopodium cernuum, and a whole bunch of other synonyms. In Hawai'i the name for the plant is wāwaeʻiole, or "rat's foot".
It grows in the tropics worldwide, favouring bogs, especially in mountainous areas. It only grows as far south as New Zealand because the hydrothermal areas are hot, moist, acidic, and fully exposed to the sun.
Lycopods are vascular plants that first appeared in the fossil record during the Silurian period, 444 - 419 million years ago. They're especially abundant in coal deposits, and formed extensive forests by the subsequent Devonian. Palhinhaea cernua is the largest of the living clubmosses, having rhizomes up to 5m in length, with leafy uprights up to half that, but some of the extinct species had trunks 50m high.
The life cycle of lycopods include an independent sporophyte stage and a long-lived gametophyte stage. The sporophytes (as seen here) produce single-celled spores that disperse and germinate into small gametophytes that eventually produce the eggs and sperm. In this genus and its relatives the gametophytes grow on the surface of the soil and are partially photosynthetic, but have a symbiotic relationship with soil fungi as well. In other genera the gametophyte grows underground and relies entirely on the fungi. After fertilization, the embryos grow into sporophytes again.
Lycopod spores are highly flammable, and are used in fireworks and flash powders.
Craters of the Moon, Taupo Volcanic Zone, New Zealand
