| Rhodochorton | |
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| Rhodochorton purpureum | |
Scientific classification  | |
| Domain: | Eukaryota |
| Clade: | Archaeplastida |
| Division: | Rhodophyta |
| Class: | Florideophyceae |
| Order: | Acrochaetiales |
| Family: | Acrochaetiaceae |
| Genus: | Rhodochorton Nägeli [1] |
| Species | |
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Rhodochorton is a genus of filamentous red alga adapted to low light levels. It may form tufts or a thin purple "turf" up to 5 millimetres high. The filaments branch infrequently, usually at the tips. [2]
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.[ verification needed ] [8]
The gametophyte may replicate using monospores, but produces sperm in spermatangia, and "eggs"(?) in carpogonium. [8]
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