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Beautiful Swallowtail

Philinopsis speciosa

  • Molluscs
  • IUCN: Not evaluated
  • Usual depth3–18 m
  • Water temperature15–30 °C
  • Best monthsApril, October, and November
  • How commonOccasional
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Photo credit: (c) Christopher Mark, some rights reserved (CC BY), uploaded by Christopher Mark · CC BY · iNaturalist

About this species

Philinopsis speciosa, the blue-lined philinopsis, is a species of sea slug, a shell-less opisthobranch gastropod mollusc in the family Aglajidae.

Text from the Wikipedia article “Philinopsis speciosa”, licensed CC BY-SA 4.0. Read the article

Where and when

Where it has been recorded

Worldwide

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Best months

Worldwide (open data)

  • January: 54 records
  • February: 58 records
  • March: 86 records
  • April: 95 records
  • May: 62 records
  • June: 51 records
  • July: 53 records
  • August: 71 records
  • September: 73 records
  • October: 98 records
  • November: 97 records
  • December: 69 records

Depth and water temperature

Depth

Mostly recorded at 3–18 m · Deepest record: 420 m

  • 0–10 m: 55 records
  • 10–20 m: 55 records
  • 20–30 m: 5 records
  • 30–40 m: 2 records
  • 40–50 m: 0 records
  • 50–60 m: 0 records
  • 60–70 m: 0 records
  • 70–80 m: 0 records
  • 80–90 m: 0 records
  • 90–100 m: 0 records
  • 100–110 m: 0 records
  • 110+ m: 2 records

Water temperature

Recorded in surface water of 15–30 °C

  • 14–16 °C: 1 records
  • 16–18 °C: 2 records
  • 18–20 °C: 3 records
  • 20–22 °C: 52 records
  • 22–24 °C: 11 records
  • 24–26 °C: 50 records
  • 26–28 °C: 49 records
  • 28–30 °C: 103 records

Names and classification

English
Beautiful Swallowtail, Blue-margin Headshield Slug, slipper slug
Names in 3 more languages
French
Philinopsis à lignes bleues
Japanese
カノコキセワタ, カラスキセワタ, カラスキセワタガイ
Simplified Chinese
豔麗似海牛

Other scientific names: Aglaja cyanea, Aglaja iwasai, Doridium cyaneum, Doridium guttatum, Doridium marmoratum, Philinopsis cyanea

Similar species

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).
  • 432 open-data records from 1958 to 2026.
  • Species data updated October 26, 2026.

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