RCFossils Posted January 25, 2020 Share Posted January 25, 2020 Paleozoic insects can be extremely difficult for an amateur collector to identify. Partial specimens, poor preservation and outdated publications make it nearly impossible to identify most specimens to the species level. To further compound the problem, many species names are synonymous and no longer valid. In my future posts on Mazon insects, I will not attempt to identify specimens beyond the family level unless I have a firm identification. Geraridae are known from many Paleozoic sites around the world. The first Gerarus specimens were described in 1885 by Scudder from specimens collected from the Mazon Creek Deposit. While all Mazon insects are rare, they are one of the more commonly found types. Some of the defining characteristics are the four wings are similar in in length. The wings fold back over the thorax and abdomen.The prothorax is elongated and often times has large spiny projections. One interesting note is that it has been observed that the wing veination on Geraridae can be highly variable. It can even be different from wing to wing on the same animal! This has led to dozens of species being named. Many are synonymous and no longer valid. The largest recorded specimen size is 7.5 centimeters. I have one in my collection that is slightly larger measuring 8 centimeters. There has been much debate over the lifestyle of Geraridae. Current thinking is that they were not strong fliers and may be distantly related to crickets and grasshoppers. While Geraridae are known from Paleozoic sites worldwide, they are usually flattened and preserved as a thin film making study difficult. Mazon specimens can be found inflated exposing key structures not usually seen from other sites. Professor Jarmika Kukalova-Peck extensively studied Mazon Creek insects. She used Gerarus specimens from Mazon Creek to formulate her hypothesis of the origin of insect wings. The hypothesis is still debated and much more work needs to be done. This first specimen was collected from Pit 4 (Shadow Lakes). It has wonderful preservation and is the largest known specimen that I am aware of. Jarmila Kukalova-Peck studied this specimen and thought it might be a new genus. She also figured the specimen to determine various structures and wing veination. 11 Link to comment Share on other sites More sharing options...
RCFossils Posted January 25, 2020 Author Share Posted January 25, 2020 Here is the drawing that was made by Jarmila Kukalova-Peck. 10 Link to comment Share on other sites More sharing options...
RCFossils Posted January 25, 2020 Author Share Posted January 25, 2020 This specimen is associated with a Neuropteris frond. 8 Link to comment Share on other sites More sharing options...
RCFossils Posted January 25, 2020 Author Share Posted January 25, 2020 This headless specimen shows how the wings would have naturally sat along the body 9 Link to comment Share on other sites More sharing options...
Thecosmilia Trichitoma Posted January 25, 2020 Share Posted January 25, 2020 It is better to keep your mouth closed and let people think you are a fool than to open it and remove all doubt -Mark Twain Link to comment Share on other sites More sharing options...
RCFossils Posted January 25, 2020 Author Share Posted January 25, 2020 This is the largest insect in my collection. It is a huge Archaeorthoptera. If it is a Geraridae, it is enormous. Either way, it is closely related. 7 Link to comment Share on other sites More sharing options...
RCFossils Posted January 25, 2020 Author Share Posted January 25, 2020 5 Link to comment Share on other sites More sharing options...
Nimravis Posted January 26, 2020 Share Posted January 26, 2020 Beautiful pieces Rob, I also have a drawing from Dr. Peck on a fossil in my collection. Link to comment Share on other sites More sharing options...
stats Posted January 26, 2020 Share Posted January 26, 2020 Wow! Awesome! I have seen some of the Field Museum specimens up close. I would love to find one of these someday! Cheers, Rich Link to comment Share on other sites More sharing options...
FossilDAWG Posted January 27, 2020 Share Posted January 27, 2020 You have the most astounding collection!! As an entomologist I really appreciate this glimpse at the early days of these amazing creatures. Don Link to comment Share on other sites More sharing options...
RCFossils Posted January 27, 2020 Author Share Posted January 27, 2020 1 hour ago, FossilDAWG said: You have the most astounding collection!! As an entomologist I really appreciate this glimpse at the early days of these amazing creatures. Don Thank You! More to come. Link to comment Share on other sites More sharing options...
RCFossils Posted January 27, 2020 Author Share Posted January 27, 2020 8 hours ago, Nimravis said: Beautiful pieces Rob, I also have a drawing from Dr. Peck on a fossil in my collection. Thanks Please post a picture if you have a chance. 1 Link to comment Share on other sites More sharing options...
RCFossils Posted January 27, 2020 Author Share Posted January 27, 2020 1 hour ago, stats said: Wow! Awesome! I have seen some of the Field Museum specimens up close. I would love to find one of these someday! Cheers, Rich It has been about thirty-three years since I had the opportunity to see the Field Museum collection drawer filled with Mazon Insects. I think I was around fifteen at the time. i wish I could remember the scientists name who took me behind the scenes for a personal tour. It definitely inspired me to continue collecting. Link to comment Share on other sites More sharing options...
stats Posted January 27, 2020 Share Posted January 27, 2020 1 hour ago, RCFossils said: It has been about thirty-three years since I had the opportunity to see the Field Museum collection drawer filled with Mazon Insects. I think I was around fifteen at the time. i wish I could remember the scientists name who took me behind the scenes for a personal tour. It definitely inspired me to continue collecting. I'm sure it has expanded greatly. They have Tom Testa's collection, which I heard was about 8000 specimens... many undescribed! Jack Wittry brought me and a couple others back after a FM Member Night 5 or so years ago. Awesome stuff! I've seen the plant collections a few times. My daughter was an intern last summer in Paleobotany and plans to do more this summer. Some unbelievable specimens behind the scenes! Cheers, Rich 1 Link to comment Share on other sites More sharing options...
Nimravis Posted January 28, 2020 Share Posted January 28, 2020 @RCFossils Rob per your request here is the picture drawn by Dr. Peck for one of Walter’s fossils that is in my collection. I tried the best on the picture of the fossil, it might have come out better wet. Dr. Peck identified it as a Megasecoptera nymph. 7 Link to comment Share on other sites More sharing options...
Righteous Posted January 28, 2020 Share Posted January 28, 2020 After looking at these I see a new quest now Link to comment Share on other sites More sharing options...
Ruger9a Posted January 28, 2020 Share Posted January 28, 2020 OMG.... These are the most perfect specimens I've seen … and they just keep coming! Thanks you! Link to comment Share on other sites More sharing options...
Nimravis Posted January 28, 2020 Share Posted January 28, 2020 Rob in July of 2018 I cracked this one open and @Wrangellian thought it was an insect and you confirmed, I believe that this might be a Gerarus, what do you think? 3 Link to comment Share on other sites More sharing options...
RCFossils Posted January 29, 2020 Author Share Posted January 29, 2020 10 hours ago, Nimravis said: Rob in July of 2018 I cracked this one open and @Wrangellian thought it was an insect and you confirmed, I believe that this might be a Gerarus, what do you think? I cannot say for sure but think it is likely some type of geraridae. It has really nice veination on the wings. 1 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now