Slender Sap Sucking Slug
Thuridilla gracilis
- Usual depth2–17 m
- Water temperature19–30 °C
- Best monthsAugust, November, and December
- How commonOccasional
Photo credit: (c) Georgina Jones, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist
About this species
Thuridilla gracilis is a species of sea slug, a sacoglossan, a marine gastropod mollusk in the family Plakobranchidae. It is an Indo-Pacific species that lives in or near coral reefs and eats algae.
Text from the Wikipedia article “Thuridilla gracilis”, licensed CC BY-SA 4.0. Read the article
Where and when
Where it has been recorded
Worldwide
Loading the map
Best months
Worldwide (open data)
- January: 28 records
- February: 32 records
- March: 27 records
- April: 43 records
- May: 38 records
- June: 35 records
- July: 36 records
- August: 54 records
- September: 36 records
- October: 46 records
- November: 60 records
- December: 51 records
Depth and water temperature
Depth
Mostly recorded at 2–17 m · Deepest record: 25.5 m
Water temperature
Recorded in surface water of 19–30 °C
Photos
no rights reserved · CC0 1.0 · iNaturalist 
(c) Dan Schofield, some rights reserved (CC BY) · CC BY · iNaturalist 
no rights reserved · CC0 1.0 · iNaturalist 
no rights reserved · CC0 1.0 · iNaturalist
Names and classification
- English
- Slender Sap Sucking Slug
Names in 2 more languages
- French
- Thuridille gracile
- Japanese
- シロスジミドリガイ, タスジミドリガイ
Other scientific names: Elysia gracilis
Similar species
White-marked Taco SlugThuridilla albopustulosa
Midnight Taco SlugThuridilla hoffae
- Orange-edged Sapsucking Slug
Thuridilla lineolata
Sources and credits
Names and taxonomy: WoRMS (CC BY 4.0) and the GBIF Backbone (CC BY 4.0). Photos: iNaturalist observers, each under the licence shown (CC0, CC BY or CC BY-SA).
- Depth, temperature, months and maps: records from OBIS and GBIF under CC0 or CC BY.
- Descriptions: Wikipedia, licensed CC BY-SA, each linked to its article.
- Conservation status as published by GBIF (IUCN Red List).
- 504 open-data records from 1928 to 2026.
- Species data updated October 26, 2026.
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