195g Cephalopod Nautiloid Trilacinoceras-Sinoceras Species, China - 400-600 MYO

Description

195g Cephalopod Nautiloid - Sinoceras Species, Nautiloid Trilacinoceras from the Ordovician of China
Approximately 400-600 million years old
Measures approximately 5.13 x 1.88 x 1.13"
Information on Nautiloids in Northeastern China:
Nautiloids are first known from the late Cambrian Fengshan Formation of northeastern
China
, where they seem to have been quite diverse (at the time this was a warm shallow sea rich in marine life). However, although four orders have been proposed from the 131
species
named, there is no certainty that all of these are valid, and indeed it is likely that these taxa are seriously oversplit.
Nautiloids are among the group of animals known as
cephalopods
, an advanced class of
mollusks
which also includes
ammonoids
,
belemnites
and modern
coleoids
such as octopus and squid. Other mollusks include
gastropods
,
scaphopods
and
bivalves
.