Geobulletin alpha

Source info:

Author:	Dave
Date:	2013-07-31 09:01:00
Blog:	Views of the Mahantango
URL:	http://viewsofthemahantango.blogspot.com/2013/07/eldredgeiametacryphaeus-trilobites-from.html

Summary:

In the last few years there have been some interesting Devonian aged fossils coming out of Bolivia. I have mostly been purchasing mine from this seller on E-bay. They are found in small, round concretions so you often get a mold and cast of the fossil. Among the fossils I have acquired are some fairly nice trilobites with the most common specimens labelled Eldredgeia venustus; although some specimens could be another closely related genera, Metacryphaeus. The only way to tell them apart is to count the number of lens facets that are in the eyes and by measuring the ratios of the glabellar furrows and lobes (the rounded parts on the head between the eyes). Here is a specimen contorted into a "U" shapeThis is the mold of the fossil Another specimen is curled up a little differentlyThese next two photos are of the fossil's mold....... that fits perfectly on top of the lower half. These specimens come from the Belen formation (Devonian, Eifelian stage) south of the capitol of Bolivia, La Paz.

Content analysis:

Stratigraphic context:

Recognized stratigraphic terms [n]:	Devonian [2] Eifelian [1]
Agenames chronostratigraphy [rating]:	Devonian [0.61] Paleozoic [0.61] Phanerozoic [0.61] Eifelian [0.1] Middle Devonian [0.1]

Geographic context:

Location	Country	Latitude	Longitude
Belen De Choquecota	BO	-17.9833	-67.85
Bolivia	BO	-16.2883	-63.5494
Brazil	BR	-14.2429	-54.3878
La Paz	BO	-16.499	-68.1463

Keywords:

... ..., Belen Formation, Bolivia, capitol, cast, closely related genera, common specimens, concretions, Devonian aged fossils, E-bay, Eifelian stage, Eldredgeia venustus, Eldredgeia/Metacryphaeus Trilobites, eyes, fairly nice trilobites, glabellar furrows, La Paz, lens facets, lobes, lower half, mold, number, ratios, rounded parts, seller, specimens, way