CAMBRIAN ARTHROPODS OF THE BALANG

A large extinct bivalved arthropod, Tuzoia sinesis (Pan, 1957) from Cambrian deposits of the Balang Formation. The Balang outcrops in beautiful Paiwu, northwestern Hunan Province in southern China. The site is intermediate in age between the Lower Cambrian Chengjiang fauna of Yunnan and the Lower to Middle Cambrian, Kaili Lagerstätten of Guizhou in southwestern China.

This specimen was collected earlier this week. It is one of many new and exciting arthropods to come from the site.

Balang has a low diversity of trilobites and many soft-bodied fossils similar in preservation to Canada's Burgess Shale. Some of the most interesting finds include the first discovery of anomalocaridid appendages (Appendage-F-type) from China along with the early arthropod Leanchoiliids with his atypical frontal appendages (and questionable phylogenetic placement) and the soft-shelled trilobite-like arthropod, Naraoiidae.

While the site is not as well-studied as the Chengjiang and Kaili Lagerstätten, it looks very promising. The exceptionally well-preserved fauna includes algae, sponges, chancelloriids, cnidarians, worms, molluscs, brachiopods, trilobites and a few non-mineralized arthropods. It is an exciting time for Cambrian paleontology. The Balang provides an intriguing new window into our ancient seas and the profound diversification of life that flourished there.

LATE SILURIAN EURYPTERID

The impressive homeotype specimen of Eurypterus lacustris from Late Silurian deposits in New York. UCMP Berkeley's paleontological collections.

About two dozen families of eurypterids “sea scorpions” are known from the fossil record. Although these ancient predators have a superficial similarity, including a defensive needle-like spike or telson at their tail end, they are not true scorpions. They are an extinct group of arthropods related to spiders, ticks, mites and other extant creepy crawlies.

Eurypterids hunted fish in the muddy bottoms of warm shallow seas some 460 to 248 million years ago before moving on to hunting grounds in fresh and brackish water during the latter part of their reign. Their numbers diminished greatly during the Permian-Triassic extinction, becoming extinct by 248 million years ago.

ESMERALDINA ROWEII

An Esmeraldina roweii multi-block of lovely trilobites from the Lower Lower Cambrian Poleta Formation of Esmeralda County, near Goldfield Nevada, plus a very interesting creature off to the lower left who looks to be an unidentified arthropod.

A very developed trilobite with long genal and axial spines, plus the ability to enroll. And all of this before the Olenellids existed. Collection of the deeply awesome George Walter Ast. Goldfield is located 247 miles southeast of Carson City, along U.S. Route 95.

MAMMUT AMERICANUM

The American Mastodon, Mammut americanum. Mastodons resemble elephants, but are more like elephant cousins.

A second species, Mammut pacificus, has recently been described from fossils found in Idaho and California. This specimen can be seen at the Smithsonian National Museum of Natural History. Photo credit: Guy Leahy.