Trinchesia is a genus of sea slugs, aeolid nudibranchs, marine gastropod molluscs in the family Trinchesiidae. All species were transferred to Tenellia as a result of a DNA phylogeny study in 2016. The genus was dismembered and broken into several smaller genera in 2017 with further DNA evidence and a re-interpretation of genus and family characteristics.

In yet another study, Korshunova et al., 2025 conducted a mass reassessment of Aeolidacea taxa and proposed to reverse previous motions that "lumped" taxa together indiscriminately. While The World Register of Marine Species (WoRMS) has cited Korshunova et al., 2025 across other taxonomic adjustments, in regards to Trinchesiidae, who is possibly the most controversed Aeolidean family with papers being published nearly every year from opposing camps, there has yet to be adjustments.

Trinchesia species feed on hydroids.

Species

According to Korshunova et al. (2025), it is noted that many species listed herein do not align with Trinchesia diagnostics, and belong truly to genera that have yet to be established.

Species currently included Trinchesia sensu strictissimo according to Korshunova et al. (2025):

  • Trinchesia caerulea (Montagu, 1804) - type species of Trinchesia
  • Trinchesia cuanensis(Korshunova, Picton, Furfaro, Mariottini, Pontes, Prkić, Fletcher, Malmberg, Lundin & Martynov, 2019)
  • Trinchesia diljuvia (Korshunova, Picton, Furfaro, Mariottini, Pontes, Prkić, Fletcher, Malmberg, Lundin & Martynov, 2019)
  • Trinchesia morrowae (Korshunova, Picton, Furfaro, Mariottini, Pontes, Prkić, Fletcher, Malmberg, Lundin & Martynov, 2019)

Species currently included in Trinchesia sensu latissimo according to Korshunova et al. (2025):

Species formerly in the genus Trinchesia:

  • Trinchesia alpha (Baba & Hamatani, 1963): synonym of Catriona alpha
  • Trinchesia colmani (Burn, 1961): synonym of Narraeolida colmani
  • Trinchesia midori Martynov, Sanamyan & Korshunova, 2015: synonym of Diaphoreolis midori
  • Trinchesia pustulata (Alder & Hancock, 1854): synonym of Zelentia pustulata
  • Trinchesia scintillans (M. C. Miller, 1977): synonym of Diaphoreolis scintillans
  • Trinchesia thelmae (Burn, 1964): synonym of Toorna thelmae
  • Trinchesia viridis (Forbes, 1840) synonym of Diaphoreolis viridis