Geobulletin alpha

Source info:

Author:	Dave
Date:	2015-06-01 09:01:00
Blog:	Views of the Mahantango
URL:	http://viewsofthemahantango.blogspot.com/2015/06/metacanthina-issoumourensis-trilobite.html

Summary:

I think this Trilobite is a Metacanthina issoumourensis. The key identifier, for me, is the little horn on the back of the cephalon (otherwise known as an occipital spine). The specimen is missing the genal spines which should extend about 15mm beyond the edge of the cephalon. It's been prepped in a pedestal presentation and that works somewhat as the pleural spines are not as splayed out as some specimens I've seen. There is a lot of detail missing from the eyes. Sadly, these are often neglected in some preparations as the rock is removed too quickly and takes some of the shell with it.Overall this is a rough specimen and I intend to get a better example in the future but, since it did not cost too much, is a good reference piece. This specimen came from Jebel Issoumour near Alnif in the Tafilalet region of Morocco and is dated to the Emsian stage of the Devonian.

Content analysis:

Stratigraphic context:

Recognized stratigraphic terms [n]:	Devonian [1] Emsian [1]
Agenames chronostratigraphy [rating]:	Devonian [0.5] Paleozoic [0.5] Phanerozoic [0.5] Emsian [0.1] Lower Devonian [0.1]

Geographic context:

Location	Country	Latitude	Longitude
Alnif	MA	31.1141	-5.17041
Morocco	MA	31.4342	-6.40245

Keywords:

Alnif, better example, cephalon, Devonian, Emsian stage, eyes, genal spines, good reference piece, Jebel Issoumour, key identifier, little horn, Metacanthina issoumourensis, Morocco, occipital spine, pedestal presentation, pleural spines, preparations, rough specimen, specimens, Tafilalet region, trilobite