BIOTIC Species Information for Tenellia adspersa
Researched byNicola White Data supplied byMarLIN
Refereed byDr Richard S.K. Barnes
Scientific nameTenellia adspersa Common nameLagoon sea slug
MCS CodeW1443 Recent SynonymsTenellia pallida, Embletonia pallida

PhylumMollusca Subphylum
Superclass ClassGastropoda
SubclassOpisthobranchia OrderNudibranchia
Suborder FamilyTergipedidae
GenusTenellia Speciesadspersa

Additional InformationNo text entered
Taxonomy References Howson & Picton, 1997, Picton & Morrow, 1994,
General Biology
Growth formLanceolate
Feeding methodPredator
Environmental positionEpifaunal
Typical food typesHydroids, especially %Cordylophora caspia%, Laomeda spp. and %Protohydra leuckarti% HabitFree living
BioturbatorNot relevant FlexibilityHigh (>45 degrees)
FragilityIntermediate SizeVery small(<1cm)
HeightInsufficient information Growth RateInsufficient information
Adult dispersal potentialNot researched DependencyIndependent
General Biology Additional InformationTenellia adspersa can rapidly devour hydroid colonies, exhausting its own food supply. It has been suggested that the developmental plasticity and rapid growth of this species enables it to disperse to new locations to find new food.
Biology References Antsulevich & Starobogatov, 1991,
Distribution and Habitat
Distribution in Britain & IrelandThe few British records are from the Bristol Channel and the Fleet in Dorset.
Global distributionRecorded from the eastern and western North Atlantic, Baltic, Mediterranean Sea, Black Sea, Azov Sea, Caspian Sea, Japan, Pacific coast of USA, Brazil
Biogeographic rangeNot researched Depth range1 to 34 m
MigratoryNon-migratory / Resident   
Distribution Additional InformationRecorded at depths from 1 to 34 m. The species has been observed to survive and breed in salinities from 50 psu to 5.3 psu. The ranges and ecological features of the nudibranch are very similar to the hydroid Cordylophora caspia and they co-exist everywhere, which suggests some connection. The wide geographic distribution of Tenellia adspersa is probably due to passive transportation of adults and egg masses by Cordylophora colonies on ships.

Substratum preferencesSeagrass
Artificial (e.g. metal/wood/concrete)
Small boulders
Physiographic preferencesEstuary
Isolated saline water (Lagoon)
Enclosed coast / Embayment
Biological zoneLower Eulittoral
Sublittoral Fringe
Upper Infralittoral
Wave exposureSheltered
Very Sheltered
Tidal stream strength/Water flowStrong (3-6 kn)
Moderately Strong (1-3 kn)
Weak (<1 kn)
SalinityVariable (18-40 psu)
Low (<18 psu)
Habitat Preferences Additional Information
Distribution References Picton & Morrow, 1994, Hayward & Ryland, 1995b, Antsulevich & Starobogatov, 1991, Anonymous, 1999(s),
Reproduction/Life History
Reproductive typeGonochoristic
Developmental mechanismLecithotrophic
Direct Development
Reproductive SeasonInsufficient information Reproductive LocationInsufficient information
Reproductive frequencyAnnual protracted Regeneration potential No
Life span<1 year Age at reproductive maturity<1 year
Generation time<1 year Fecundity25 to 50 eggs per spawn
Egg/propagule sizeInsufficient information Fertilization typeInsufficient information
Larval/Juvenile dispersal potential10-100m Larval settlement periodInsufficient information
Duration of larval stageInsufficient information   
Reproduction Preferences Additional InformationTenellia adspersa has a subannual lifecycle with a short generation time of as little as 20 days when reared at 20 degrees C and 30 ppt on the hydroid Cordylophora lacustris. The animals may spawn 3 to 5 times a day with 25 to 50 eggs per spawn (Chester, 1996). The spawn consists of a short, curved, lozenge-shaped mass. The period from spawning to hatching lasts 4-5 days. The method of development varies with the environmental conditions. Metamorphosis normally takes place within the egg capsule, hatching as a juvenile. In animals that have been starved a switch to pelagic non-feeding or planktotrophic development has been observed.
Reproduction References Chester, 1996,
About MarLIN | Contact, Enquiries & Feedback | Terms & Conditions | Funding | Glossary | Accessibility | Privacy | Sponsorship

Creative Commons License BIOTIC (Biological Traits Information Catalogue) by MarLIN (Marine Life Information Network) is licensed under a Creative Commons Attribution-Non-Commercial-Share Alike 2.0 UK: England & Wales License. Permissions beyond the scope of this license are available at Note that images and other media featured on this page are each governed by their own terms and conditions and they may or may not be available for reuse. Based on a work at