- present. (The librigena, or ch**** spines,
detach during moulting.) In
ptychopariids,
short bladelike genal spines are
often present on the tips of the librigena...
-
ptychopariid (specific name may be
confused with Alokistocare)
Alokistocare harrisi -
alokistocarid ptychopariid Asaphiscus wheeleri -
ptychopariid;...
-
Olenus is a
genus of
Upper Cambrian ptychopariid trilobite.
Olenus can be
found in the
British Isles, India, Norway, Sweden, Denmark, Newfoundland, Texas...
-
Bergeroniellus B.
spinosus Redlichiid trilobite Binodaspis B.
secunda Ptychopariid trilobite Sinskolutella S.
ordinata Bradoriid Yakutingella Y. intricata...
-
Cambroproteus is a
genus of
ptychopariid trilobite from the Late
Cambrian of Morocco. It has a
single known species,
Cambroproteus lemdadensis,
whose various...
-
Ptychoparia is a
genus of
ptychopariid trilobites, and is the type
genus of the
family Ptychopariidae, and the
order Ptychopariida.
Fossils of the various...
-
Olenidae is a
family of
ptychopariid trilobites. Some genera,
Balnibarbi and Cloacaspis, are
thought to have
evolved a
symbiotic relationship with sulfur-eating...
-
earliest trilobites known from the
fossil record are
redlichiids and
ptychopariid bigotinids dated to
around 520
million years ago.
Contenders for the...
-
Yunnanocephalus is a
genus of
ptychopariid trilobite. It
lived during the late
Atdabanian and
Botomian stages, in what are
currently Antarctica, Australia...
-
Holotrachelidae and
Hystricuridae (considered
Proetida before),
combined with the
Ptychopariid families Alokistocaridae, Crepicephalidae, Ehmaniellidae, Marjumiidae...