Exeomastix
| Exeomastix | |
|---|---|
 | |
| Holotype under natural light (A, B) and coated in alcohol for improved visualization (C, D) | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Division: | Teleostei |
| Order: | Scombriformes |
| Family: | Trichiuridae |
| Genus: | †Exeomastix Calzoni, Giusberti & Carnevale, 2026 |
| Species: | †E. zabimaru |
| Binomial name | |
| †Exeomastix zabimaru (Calzoni, Giusberti & Carnevale in Calzoni et al., 2026) | |
| Synonyms | |
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Exeomastix (lit. 'former dawn whip') is an extinct genus of cutlassfish (family Trichiuridae) known from the early Eocene (Ypresian age) Chiusole Formation of Italy. The genus contains a single species, Exeomastix zabimaru, known from a skeleton preserved on a slab and counterslab. It is characterized by its thin, ribbon-like body form, a fang at the front of the upper jaw, and a reduced, forked caudal fin. Exeomastix is the oldest trichiurid in the fossil record known from articulated remains.