Rhodochorton

In most species of Rhodochorton, the spore does not persist in the mature plant; instead, a basal web of filaments acts as a holdfast. Indeed, all Rhodochorton species have distinct basal threads, usually forming a disc, and upright threads, which are typically thinner.[2] Lateral branches usually occur at or near the top of the patent cell, and branching is concentrated towards the tips of threads.[2]

The organism may encrust bare rock surfaces, or be epiphytic upon frondose algae - particularly Laminaria hyperborea.[3] It typically grows in the shadow of these larger algae, in the intertidal zone,[4] and its adaption to low light levels means it is also common in caves.[2] It reproduces in winter using tetrasporangia and don't bear any monosporangia.[5] Rhodochorton is typically marine, but R. investiens dwells in fresh water.[6] Sexual reproduction has never been observed.[7]

It suffers grazing pressure from gastropods and amphipods, but amazingly fragments of the algae are able to pass through the grazers' digestive tracts alive - grazing may actually form a mode of dispersal for the organism.[4]

Rhodochorton investiens displays a relatively simple life cycle for a red alga.[8]

In the Carposporophyte: a spermatium merges with a trichogyne (a long hair on the female sexual organ), which then divides to form carposporangia - which produce carpospores.

Carpospores germinate into gametophytes, which produce sporophytes. Both of these are very similar; they produce monospores from monosporangia "just below a cross wall in a filament"[8] and their spores are "liberated through apex of sporangial cell."[8]

The spores of a sporophyte produce tetrasporophytes. Monospores produced by this phase germinate immediately, with no resting phase, to form an identical copy of parent. Tetrasporophytes may also produce a carpospore, which germinates to form another tetrasporophyte.[8]

The gametophyte may replicate using monospores, but produces sperm in spermatangia, and "eggs"(?) in carpogonium.[8]

The species in the genus Rhodothamniella closely resemble Rhodochorton