Limulus

Limulus is a genus of horseshoe crab, with one extant species, the Atlantic horseshoe crab (Limulus polyphemus). One fossil species is currently assigned to the genus though several other species have been named, which have since been assigned to other genera.

Limulus Temporal range: Maastrichtian–Present PreꞒ Ꞓ O S D C P T J K Pg N
Modern L. polyphemus compared to the very similar Jurassic Crenatolimulus darwini
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Chelicerata
Order:	Xiphosura
Family:	Limulidae
Genus:	Limulus O. F. Müller, 1785[1]
Type species
Monoculus polyphemus[1] Linnaeus, 1758
Synonyms
Xiphosura

Currently valid species include:^[2]

• Limulus polyphemus (Linnaeus, 1758)
• Limulus coffini† Reeside & Harris, 1952- Pierre Shale, United States, Late Cretaceous (Maastrichtian)

Doubtful species include:^[3]

• Limulus nathorsti† Jackson, 1906- Jurassic, Sweden

Tentative species:^[3]

• "Limulus" decheni† Zinken, 1862- Paleogene, Germany (considered by some intermediate between Limulus and Tachypleus)^[3]