RGBAstas

RGBAstas is a fictional genus of unicellular photosynthetic protists notable for a four-pigment system that echoes the red, green, blue, and alpha channels of digital color models. In this article, RGBAstas is described as a small, green-algae–like lineage with a stable arrangement of pigments that enables distinctive color signals under mixed lighting.

In the in-universe taxonomy, RGBAstas is placed among the green algae within the domain Eukaryota, commonly grouped in speculative Chlorophyta lineages as RGBAstaceae.

The genus was first described by marine biologist Elena P. Duarte in 2004 after isolation from a temperate kelp forest off the Azores. The name combines the RGBA acronym with the Greek-stem -stas, intended to reflect a stable, four-pigment configuration.

Cells are 5–8 micrometers long, ovoid to ellipsoidal, with a single nucleus and a cup-shaped chloroplast. Four major pigments are identified: a chlorophyll a/b complex (green), a red pigment analogous to phycoerythrin, a blue pigment akin to phycocyanin, and a UV-absorbing alpha pigment. The pigment suite gives RGBAstas a variable green hue with red, blue, and purple overtones under different light.

Found in coastal and estuarine waters in temperate regions; planktonic and occasionally sessile near macroalgae. Reproduction is primarily asexual binary fission; a sexual phase has been observed under nutrient stress.

RGBAstas coloratus—characterized by strong red fluorescence; RGBAstas chromatus—dominant blue tints; RGBAstas humilis—smallest described species.

The RGBA pigments are of interest for studies on light harvesting and may inspire bio-inspired colorimetric sensors. Note: RGBAstas is a fictional genus created for illustrative purposes.