Western Trilobites Association

FIELD TRIPS

 

WTA FIELD TRIP #3 OCTOBER 2004

Report by: Richie Kurkewicz
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Over the course of the week long trip we had six diggers accompanied by a motley crew of friends, wives, and dogs.  Not all of us were together at any one time, but every day a different combination toiled under a brutal Nevada sun; which systematically broke down our middle-aged, pot-bellied, pathetically out-of-shape bodies.  Actually… the weather was perfect.

On the first day Andrew Milner (photo) and I hooked up at the Half Moon Mine in the Chisholm.  Andrew had discovered a new site high up in the Chisholm where we broke a lot of rock to find rare Zacanthoides cf. serratus.  After about three hours we collected about 5 specimens of this very rare bug.

As an aside, Andrew and Fred are collaborating on a future paper concerning the Chisholm sequence that clearly shows the evolutionary trail of the Piochaspis.  After all the picking over that has incurred in the Chisholm Shale around the Half Moon Mine, this area still has some secrets left to unveil.

Day two and three found me going solo, striking out in the Highland Range searching for Mexicella etc.  When found, these bugs often seem to be in small pockets.  So it can be very hit and miss……. I missed.  I also did some collecting in the lower Pioche Shale.  My most interesting find was an Oryctocephalites palmeri with the body features present.  Before this find, all I had ever seen of this species were pretty little pink outlines with little or no body features present.

On day four George arrived at our rendezvous at the world famous Clown Motel in Tonopah (the symbolism of this needs little interpretation!). The fact being neither of us had not collected in Esmeralda County before, we had a full slate of potential collecting sites to visit.  Here we were to hook-up for the first time with Brian and Norm and their entourage.  They are friends of Stu Hollingsworth and evidently have done some digs together.  They were most familiar with the L. Cambrian, Poleta Fm. in the area, and had collected in Esmeralda county area a few times prior.  They led us to a beautiful site high up in the Montezuma Range in search of the most highly coveted Nevadia and Esmeraldina.  The site extends over a series of rolling forested hills for many tens of acres (photo).  For a trilobite collector to find a large complete one of these elusive bugs is a transcendent experience. Complete specimens are quite rare.  They can reach up to six inches when found and the preservation is breath taking. Dustin Rooks, who joined us later that afternoon, found this large partial (photo).

Brian, Norm and friends were camped out for a few days at this location.  To the best of my knowledge none of them found a magnificent specimen during their stay.  Just many tantalizing partials, or smaller specimens. 

Later that afternoon, George and I decided to move on to survey and find other new sites, as our time was limited.  We left the Nevadia site to look for the Split Mountain Sundberg/McCollum trench.  Unfortunately, we missed the turn-off and snaked up a canyon to a literal dead-end.  We now know where the turn-off is and shall return on the next trip. 

With the day coming to a close we decided to check out the Goldfield Hills on our way back to Tonopah.  Dustin had told us about a small roadside outcrop of shale where he had found a few small ptychopariiads recently (photo). We located it, and within the short time we surface collected and discovered not only the ptychopariid species that Dustin had found, but also a few agnostids.  Now, this peaked our curiosity, as neither of us had ever collected a Cambrian agnostid in Nevada.  We decided to come by the next day for a full day at this location.

Travelling note:  Tonopah is a small Nevada mining town now in a state of arrested decline.  It survives mostly as a stopover for weary travelers on their way somewhere else.  So, it somewhat of a challenge to find fine dining.  George and I did find the two of the best culinary bets.  There is a Mexican place on the West Side of town that has great salsa, a good bar and OK food.  Also, in the town center is a fish fry place that is tolerable.  Please be advised that both eateries require at least a tank top and some kind of minimal foot ware to enter.

Day five found George and I going back to the Goldfield Hills area.  We first checked out a McCollum/Sundberg site in a small gulch off of a remote ranch trace trail.  Here we found a few of what Fred tentatively id'd as Syspacephalus  variosus.  We then returned to the prior days quarry site where we met Dustin and spent the rest of the day collecting there. The days dig ended with a small collection of two ptychopariid species and one, or possibly two agnostid species and one spiny pygidium that I have not tried to have id'd yet.

When I returned to S.F. I sent a few photos of the specimens to Fred and he replied with some exciting news.  " These are the first reported trilobites of the Elvinia Biozone, Steptoean Stage (other than a very simple, very small elviniid that I found at Goldfield in limestones)."  And " The trilobites from the Emigrant were indeed interesting, but probably nothing new.  My primary reference in identifying the specimens was “Upper Steptoean (Upper Cambrian) trilobites from the McKay Group of Southeastern British Columbia, Canada” by Brian Chatterton and Rolf Ludvigsen, 1998, JP Memoir 49."  Fred id'd the specimens as most likely Labiostria westropi, Wujiajiania sutherlandi and Pseudagnostus communis.  Fred is interested in pursuing this and co-authoring a note with Dustin and I to submit to the Journal of Paleontology. (See 4, 4a, 4b)

Day six saw George, Brian and Norm head down to the Groom Range.  Brian had truck problems upon entering the ranch road to the site and was delayed in arriving.  George went solo and collected a large number of specimens.  He thinks he may have collected more species than the ubiquitious Kochiella and Syspacephalus.  I'm still waiting for him to sort his finds and photograph them. Brian, when back from collecting, found a large inflated trilobite species, which he could not id up in the Ogygopsis beds. I hope he will soon provide a photo for one of our id experts to take a look at.

This concludes my report. I know that Brian has found some interesting arthropods and soft-bodied creatures in the Poleta, and am awaiting photos and information.  Same with George.  They, or I, will forward anything interesting to the members. 

The next WTA Field Trip is tentatively scheduled for the end of March, 2005.

Cheers!~!

Richie