Belemnoidea

Belemnoids
Temporal range: Devonian–Cretaceous
Well preserved diplobelid Clarkeiteuthis conocauda, showing arm hooks and outline of mantle
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Coleoidea
Superorder: †Belemnoidea
Orders

Aulacocerida
Phragmoteuthida
Belemnitida
Diplobelida

Artist's reconstruction of belemnoids.

Belemnoids are an extinct group of marine cephalopod, very similar in many ways to the modern squid. Like them, the belemnoids possessed an ink sac,[1] but, unlike the squid, they possessed ten arms of roughly equal length, and no tentacles.[2] The name "belemnoid" comes from the Greek word βέλεμνον, belemnon meaning "a dart or arrow" and the Greek word είδος, eidos meaning "form".[3]

Belemnoids include belemnites (which belong to the order Belemnitida), aulacocerids (order Aulacocerida), phragmoteuthids (order Phragmoteuthida), and diplobelids (order Diplobelida). Belemnoidea has been suggested to be paraphyletic by some authors.[4]

  1. ^ Lehmann, U. 1981. The Ammonites: Their life and their world. London: Cambridge University Press.
  2. ^ Doyle, P.; Shakides, E. V. (2004). "The Jurassic Belemnite Suborder Belemnotheutina". Palaeontology. 47 (4): 983–998. Bibcode:2004Palgy..47..983D. doi:10.1111/j.0031-0239.2004.00395.x. S2CID 129794707.
  3. ^ Webster's New Universal Unabridged Dictionary. 2nd ed. 1979.
  4. ^ Fuchs, Dirk; Iba, Yasuhiro; Tischlinger, Helmut; Keupp, Helmut; Klug, Christian (October 2016). "The locomotion system of Mesozoic Coleoidea (Cephalopoda) and its phylogenetic significance". Lethaia. 49 (4): 433–454. Bibcode:2016Letha..49..433F. doi:10.1111/let.12155. ISSN 0024-1164.