Globampyx

Globampyx is an extinct genus raphiophorid trilobites. It lived during the later part of the Arenig stage of the Ordovician Period,^[1] approximately 478 to 471 million years ago.^[1] Species of the genus are known from Canada (southeastern British Columbia), Norway (Svalbard) and Sweden.

Globampyx Temporal range: Late Arenig PreꞒ Ꞓ O S D C P T J K Pg N
G. trinucleoides
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	†Trilobita
Order:	†Asaphida
Family:	†Raphiophoridae
Genus:	†Globampyx Fortey, 1975
Species
G. trinucleoides Fortey, 1975 (type) G. obtusus (Moberg & Segerberg, 1906) synonym Ampyx obtusus G. linnarssoni (Schmidt, 1894) synonym Ampyx linnarssoni G. sinalae Norford & Ross, 1978

Distribution

• G. sinalae is known from the Middle Ordovician of Canada (Orthidiella brachiopod zone, Glenogle Shales Formation, North White River Section, British Columbia, 471.8-468.1 Ma)
• G. trinucleoides is known from the Middle Ordovician of Svalbard (Psephosthenaspis microspinosa small shelly zone, Olenidsletta Member, Valhallfonna Formation, Ny friesland, 471.8-457.5 Ma)

Description

The headshield (or cephalon) of Globampyx is densely covered with very small granules. The central raised area of the cephalon (or glabella) has an inverted flask-shape. It lacks the rapier-like glabellar spine of many other raphiophorids, but only has a tubercle. The thorax has five segments. The short but wide triangular pygidium, with a rather low axis (or rhachis) of up to six indistinct rings that reaches the faint border furrow.^[2]

References

1. Sepkoski, Jack (2002). "A compendium of fossil marine animal genera (Trilobita entry)". Bulletins of American Paleontology. 364: 560. Archived from the original on September 5, 2006. Retrieved 2008-01-12.
2. Fortey, R.A. (1975). The Ordovician Trilobites of Spitsbergen [II. Asaphidae, Nileidae, Raphiophoridae and Telephinidae of the Valhallfonna Formation]. Norsk Polarinstitutt Skrifter. Vol. 162. Oslo: Norsk Polarinstitutt.