Mosirites

Genus of anisoceratid ammonite from the Upper Albian to Lower Cenomanian

Mosirites Temporal range: Upper Albian to Lower Cenomanian, 105–99.7 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Subclass:	†Ammonoidea
Order:	†Ammonitida
Suborder:	†Ancyloceratina
Family:	†Anisoceratidae
Genus:	†Mosirites Shigeta et al., 2023
Type species
†Mosirites mirabilis Shigeta et al., 2023
Species
†M. mirabilis Shigeta et al., 2023 †M. serpentiformis Shigeta et al., 2023

Mosirites (IPA: [ˌmɒrsiˈɾaɪtis]) is a genus of anisoceratid ammonite from Hobetsu in Hokkaido; North Japan. The type species is Mosirites mirabilis, known from multiple partial and complete specimens.^[1]

Description

Mosirites is known from multiple specimens which were described in 2023 by Shigeta et al., (2023). The holotype, HMG-2412 has a maximum diameter of 325 mm (12.8 in), and consists of a phragmocone and a part of the body chamber with length of about 150°.^[1]

Etymology

The generic name, Mosirites (IPA: [ˌmɒrsiˈraɪtɛs]), is derived from the Ainu word for peaceful land or Hokkaido, and the suffix "-ites" which is common in ammonite genera. The type species' specific name, mirabilis (IPA: [ˌmiraˈbilis]), is a Latin word for amazing, and refers to its amazing and wonderful form. The second species' specific name, serpentiformis (IPA: [ˌsɛrpɛntiˈfoːrmis]), derives from the Latin words 'serpens' (IPA: [sɛrpɛns]) and 'forma' (IPA: [foːrma]) and refers to its snake-like form.^[1]

References

^ ^a ^b ^c Shigeta, Yasunari; Nishimura, Tomohiro; Izukura, Masataka (23 June 2023). "Mosirites, a New Cretaceous Heteromorph Ammonoid Genus from Hokkaido, Japan". Paleontological Research. 28 (2). doi:10.2517/PR220032. S2CID 259579262. Retrieved 25 July 2023.

Notable fossil cephalopods (listed by first occurrence)

Cenozoic

The belemnite-cuttlefish-like Belosaepia

Evolution of
cephalopods

Mesozoic

Advanced nautiloids Nautilaceae True ammonites
Early coleoids Muensterelloidea Proteroctopus Styletoctopus Keuppia Palaeoctopus Paleocirroteuthis Vampyronassa
Ceratitid ammonoids late Nautilida
Advanced belemnoids Diplobelids: Diplobelus Belemnites: Belemnites Belemnopsis Belemnotheutis

Palaeozoic

Earliest unambiguous cephalopods: Plectronocerida: Plectronoceras, Monoplacophora-like form: Knightoconus? First appearance of long-lasting lineages Goniatite and ceratite ammonoids Probable coleoid ancestor Bactritida Early coleoids: Jeletzkya?, Gordoniconus, Syllipsimopodi Earliest belemnoids: Aulacocerids Phragmoteuthids
Early forms the earliest cephalopod group Ellesmerocerida Orthocones: Endocerida, Orthocerida, Actinocerida Brevicones: Ascocerida, Oncocerida Earliest coiled cephalopods: Tarphycerida Spirulid?: Shimanskya