Elysia chlorotica
Famous for retaining stolen chloroplasts as internal solar panels, this sea slug laid eggs on the Seagrass Meadow glass in December 2024, the clutch hatched, and the adult was found dead on the Marine Shore three days later.
Famous for retaining stolen chloroplasts as internal solar panels, this sea slug laid eggs on the Seagrass Meadow glass in December 2024, the clutch hatched, and the adult was found dead on the Marine Shore three days later.
Elysia chlorotica is a sacoglossan sea slug native to the Atlantic coast of North America, from Nova Scotia south through Florida and into the Gulf Coast. It inhabits shallow intertidal and subtidal zones in seagrass beds, algae mats, and rocky shorelines where its primary food, the filamentous yellow-green alga Vaucheria litorea, grows in mats. The animal's bright green color comes not from its own pigmentation but from chloroplasts retained inside its body after feeding.
The process is kleptoplasty: when Elysia chlorotica grazes on Vaucheria, it punctures algal cells and sucks out the contents, retaining the intact chloroplasts in the cells lining its digestive gland. Those stolen chloroplasts continue to photosynthesize inside the slug's body for weeks to months, providing supplemental nutrition through light energy. A well-fed slug that has loaded its tissues with kleptoplasts can survive for months on light alone without eating. This makes Elysia chlorotica one of the most biologically unusual animals in the marine world, a metazoan that briefly operates as a photosynthetic organism.
Elysia chlorotica has a lifespan of roughly 9 to 12 months. Reproduction is sexual; individuals are simultaneous hermaphrodites. Eggs are laid in tightly coiled ribbons on hard substrate, typically glass, rock, or algae mats. Larvae are free-swimming veliger trochophores that require a suitable food source to settle and metamorphose. Survival of larvae through the plankton to settlement in a closed, food-limited system is uncertain.
In its natural intertidal habitat, Elysia chlorotica is a specialized herbivore of Vaucheria algae, and its population dynamics are closely coupled to that alga's availability. In miniBIOTA's Seagrass Meadow, its ecological role as an algae grazer would have been limited by the availability of suitable food; the full extent of its grazing during its time in the system is not documented.
What is documented is reproduction: the December 2024 egg clutch on the Seagrass Meadow glass is the primary ecological signal. The eggs hatched, veliger larvae were produced, but whether any larvae survived long enough to settle and develop in miniBIOTA is unknown. The death observation on December 23, 2024 confirms the adult's loss. No subsequent adult Green Sea Slugs have been recorded; the population is Extirpated.
Introduction context: No introduction event is recorded. Introduction method and source origin are not documented. Elysia chlorotica is a native Florida coastal species that could have arrived as a hitchhiker in live rock, seagrass, or other marine materials introduced to the saltwater system.
One adult Elysia chlorotica was present in the Seagrass Meadow in December 2024. It laid eggs that hatched before the adult was found dead on the Marine Shore on December 23, 2024. No subsequent adults have been observed. Whether hatched larvae survived to settlement is unknown. Population is Extirpated. The prior DB date_last_observed of December 20, 2024 has been corrected to December 23, 2024.
Primary Consumer and specialized herbivore. Feeds by puncturing algal cells and extracting contents; retains functional chloroplasts (kleptoplasts) in its digestive gland, where they continue to photosynthesize and provide supplemental nutrition to the slug. This kleptoplasty allows a well-fed individual to survive for months on light alone without additional food. In miniBIOTA, direct feeding behavior was not observed; trophic role is based on species biology. Availability of Vaucheria or similar filamentous algae is the likely limiting factor for sustained presence in the Seagrass Meadow.
Saltwater species; native to shallow intertidal Atlantic habitats. Sensitive to hydrogen sulfide; H2S toxicity was noted as a possible cause of death in the December 23, 2024 observation. Requires access to Vaucheria or similar filamentous algae for long-term survival.
Eggs were laid on Seagrass Meadow glass in early December 2024; hatching observed December 19-20. Free-swimming veliger trochophore larvae require appropriate settlement conditions and food source; no juvenile Green Sea Slugs were subsequently documented.
Follow this species across the habitats where it currently appears in the miniBIOTA biosphere.
