The base of the Langhian is defined by the first appearance of
foraminifer species
Praeorbulina glomerosa and is also coeval with the top of
magnetic chronozone C5Cn.1n. A
GSSP for the Langhian Stage was not yet established in 2009. The top of the Langhian Stage (the base of the Serravallian Stage) is at the first occurrence of fossils of the
nanoplankton species
Sphenolithus heteromorphus and is located in magnetic chronozone C5ABr. The Langhian is coeval with the
Orleanian and
Astaracian European Land Mammal Mega Zones (more precisely: with
biozones MN5 and MN6, MN6 starts just below the Langhian-Serravallian boundary), with the upper
Hemingfordian to mid-
Barstovian North American Land Mammal Ages, with mid-Relizian to Luisian
Californian regional stages (the Luisian extends barely into the early Serravallian), with the early-mid Badenian
Paratethys stage of Central and eastern Europe, with the Tozawan stage in
Japan (which runs barely into the early Serravallian), with the late Batesfordian through Balcombian to early Bairnsdalian
Australian stages and with the mid-Cliffdenian to mid-Lillburnian
New Zealand stages. ==Paleontology==