Stromie

Stromie is a term used in speculative biology and science fiction to describe a small, colonial marine cnidarian‑like organism. The name combines “strom-” from storm or stroma and the diminutive “-ie” to signify a small form. In most renderings, stromies form upright, branching colonies built from modular polyps.

Description: Each module, or polyp, measures 1–3 cm. Colonies reach up to 40 cm. The tissue is translucent with bluish bioluminescent tips. They lack a hard skeleton, relying on a proteinaceous matrix for structure.

Habitat and range: Tropical and subtropical shallow seas, typically found at depths of 10–60 m.

Ecology: Stromies feed by mucous-filtering and capture zooplankton; colonies provide microhabitat for small crustaceans. They are preyed upon by certain reef fishes and compete with sponges for space on reef substrates.

Reproduction: Asexual budding forms new modules; sexual reproduction occurs via release of brief, free‑swimming planula‑like larvae. Colonies can regenerate damaged modules over time.

Discovery and use: Stromie appears in thought experiments and fictional ecosystems as a model for evaluating colony organization, energy budgets, and modular growth in marine life. While it has been discussed in speculative contexts, stromies are not an accepted taxon in real-world biology.

Notes: In some fiction, stromies exhibit bioluminescent responses to water movement, creating the impression of shifting, storm-like patterns in the colony. See also colonial organisms, bioluminescence, cnidarians, speculative biology.