Euhoplites is an extinct ammonoid cephalopod from the Lower Cretaceous, characterized by strongly ribbed, more or less evolute, compressed to inflated shells with flat or concave ribs, typically with a deep narrow groove running down the middle.

In others the ribs are flexuous and curve forward from the umbilical shoulder and lap onto either side of the venter.

Fossils of this animal are commonly found in Lower Cretaceous, middle to upper Albian age strata.

The function of these adornments are unknown, although they may have been a source of hydrodynamic drag, preventing Euhoplites from swimming at high speeds.

Euhoplites has been found in Middle and Upper Albian beds in France where it is associated respectively with Hoplites and Anahoplites, and with Pleurohoplites, Puzosia, and Desmoceras; in the Middle Albian of Brazil with Anahoplites and Turrilites; and in the Cenomanian of Texas.

Euhoplites is closely related to Hoplites and to other hoplitid genera such as Epihopites and Protohoplites included in the subfamily, Hopliitinae.

[1] Synonyms:[1][2] Lateral ends of lautiform ribs that are strongly bent forward forms blades around concave furrow on the venter.

[1][3] Synonyms:[1] Ammonite with strong lautiform ribs that are curved forward in the last third of the flank.

Old synonyms can be ordered by thickness from most compressed to thickest as E. lautus, E. truncatus, E. opalinus, E. nitidus and E. proboscideus.

Sigmoid ribs ends at the venter, where they create crenulations by both sides of siphonal canal.

[4] Synonyms:[1] Species with sigmoid ribs that tends to form crenulations on the ventro-lateral shoulder.

Lautiform ribs begins at spiny umbilical tubercules and are tending strongly forward.

They are joining at the strongly developed ventro-lateral clavi, which are pinched obliquely to siphonal line and are alternating on both sides.