Forskal's sidegill slug
Pleurobranchus forskalii
- Usual depth1–15 m
- Water temperature19–30 °C
- Best monthsFebruary, April, and May
- How commonOccasional
Photo credit: (c) Ewout Knoester, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist
About this species
Pleurobranchus forskalii is a species of side-gill sea slug, a notaspidean, a marine gastropod mollusk in the family Pleurobranchidae.
Text from the Wikipedia article “Pleurobranchus forskalii”, 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: 55 records
- February: 124 records
- March: 123 records
- April: 151 records
- May: 127 records
- June: 76 records
- July: 79 records
- August: 90 records
- September: 112 records
- October: 100 records
- November: 105 records
- December: 87 records
Depth and water temperature
Depth
Mostly recorded at 1–15 m · Deepest record: 41.2 m
Water temperature
Recorded in surface water of 19–30 °C
Photos
(c) Susan Prior, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Franz Anthony, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Jay Paroline, some rights reserved (CC BY) · CC BY · iNaturalist 
no rights reserved · CC0 1.0 · iNaturalist 
(c) Jay Paroline, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Franz Anthony, some rights reserved (CC BY) · CC BY · iNaturalist 
(c) Ewout Knoester, some rights reserved (CC BY-SA) · CC BY-SA · iNaturalist
Names and classification
- English
- Forskal's sidegill slug, Forskal's side-gilled sea slug, Forskal's sidegilled slug
Names in 1 more languages
- German
- Forskals Flankenkiemenschnecke, Forskals Flankenkiemer
Other scientific names: Oscanius semperi, Pleurobranchus (Oscanius) semperi, Pleurobranchus (Pleurobranchus) forskalii, Pleurobranchus forskali, Pleurobranchus perrieri, Pleurobranchus semperi, Susania ceylonica, Susania karachiensis
Similar species
Lemon pleurobranchBerthellina citrina
Orange GumdropBerthellina delicata
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).
- 415 open-data records from 1907 to 2026.
- Species data updated October 26, 2026.
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