Blue Velvet Headshield Slug
Chelidonura varians
A velvety reef predator that hunts flatworms with surprising efficiency.
About
The Blue Velvet Headshield Slug (Chelidonura varians) is a cephalaspidean sea slug native to the Indo-West Pacific, where it lives a benthic lifestyle creeping across reef flats and sandy substrates in tropical waters. Despite being listed here under freshwater invertebrates, it is strictly a marine animal requiring stable reef-quality saltwater conditions. Its body is a deep, rich black overlaid with vivid blue and orange-edged markings, and the characteristic headshield, a flattened, paddle-like structure at the front, immediately sets it apart from nudibranchs that newer hobbyists might confuse it with. In the aquarium, this slug is best known as a targeted predator of polyclad flatworms, particularly the notorious Convolutriloba species that can plague reef tanks. It actively hunts these pests across rockwork and sandbed, making it genuinely useful rather than purely ornamental. That said, once the flatworm population crashes, the slug typically starves, since it is an obligate specialist and will not accept substitute foods. This is the central challenge of keeping Chelidonura varians, and it is why this species is firmly in the advanced category. Plan carefully for its long-term nutrition before adding one, and consider it a short-term intervention rather than a permanent resident.
Similar species
Other invertebrate you might consider
Good tank mates
Species that tend to coexist peacefully with Blue Velvet Headshield Slug
From the same region
Share the same natural habitat. Great for a biotope-themed tank
Frequently asked questions
- How big does the Blue Velvet Headshield Slug get?
- The Blue Velvet Headshield Slug reaches about 0.5–3" as an adult.
- What size tank does the Blue Velvet Headshield Slug need?
- A minimum of 15 gallons is recommended for the Blue Velvet Headshield Slug.
- What water parameters does the Blue Velvet Headshield Slug need?
- The Blue Velvet Headshield Slug does best with a temperature of 70–78°F, a pH of 8.1–8.4, hardness around 8–12 dGH.
- Is the Blue Velvet Headshield Slug aggressive?
- The Blue Velvet Headshield Slug is generally peaceful and suits a community tank with similarly calm tankmates.
- What does the Blue Velvet Headshield Slug eat?
- The Blue Velvet Headshield Slug is a carnivore. It needs a meaty, protein-rich diet of frozen or live foods.
- How long does the Blue Velvet Headshield Slug live?
- With good care, the Blue Velvet Headshield Slug typically lives 2-3 years.
- Is the Blue Velvet Headshield Slug reef safe?
- The Blue Velvet Headshield Slug is generally considered reef safe.