Insect and Vertebrate Faunas of a Unique Late Triassic Freshwater Ecosystem in Eastern North America

北美洲东部独特的晚三叠世淡水生态系统的昆虫和脊椎动物动物群四足动物的全球记录很好，包括最早的哺乳动物、鳄鱼、海龟、蜥蜴(青蛙和火蜥蜴)、蝶齿动物，以及它们的姊妹分类单元蜥蜴。相比之下，现代动物中最重要的一类--昆虫--的记录要差得多。世界上只有少数几个丰富的产虫三叠纪层序为人所知，这些地区的大多数化石都是不完整的标本，如孤立的翅膀和鞘翅目。在北美东部的纽瓦克超级群中，发现了一个单一的地点，其中包含许多完整的晚三叠世昆虫。Solite采石场位于弗吉尼亚州-北卡罗来纳州交界处，它创造了水虫、蓟马和卡迪蝇的最古老的全球记录。到目前为止，发现的其他化石包括一种独特的滑翔爬行动物和大量小型水生爬行动物的标本，这些标本经常保存着它们柔软部分的解剖细节。这些都还没有得到充分的描述。只挖掘了一小部分化石序列，PI将在产量最高的采石场单位进行大规模挖掘。下一阶段的工作将是对所有发现进行详细研究，并将它们与两个最相似的主要组合进行比较：吉尔吉斯斯坦的马迪根组和南非的莫尔特诺组。对Solite昆虫的精心保存将使人们能够对俄罗斯和南非的大量昆虫收藏进行全面的重新评估，从而更好地了解在这个关键时刻昆虫进化和辐射的模式和节奏。长期以来，Solite采石场被认为基本上不是化石。当然，在正常的光照条件下，微小的昆虫化石很容易被忽视。搜索图像对PI的成功至关重要，他们使用相同的方法确定了附近也有昆虫遗骸的其他地点。连同多样化的植物和脊椎动物遗骸，他们将重建一幅晚三叠世边缘淡水生态系统的详细图景。

INSECT AND VERTEBRATE FAUNAS OF A UNIQUE LATE TRIASSIC FRESHWATER ECOSYSTEM IN EASTERN NORTH AMERICANicholas C. Fraser and David A. GrimaldiEAR-0106309The end of the Triassic period (230 -200 mya) was a pivotal time in the evolution of modern terrestrial ecosystems. There is a good global record for tetrapods, including the first mammals, crocodiles, turtles, lissamphibians (frogs and salamanders), sphenodontians, and, by extension, their sister taxon, the lizards. By contrast the record for the most significant group of modern day animals, the insects, is considerably poorer. Only a handful of rich insect-producing Triassic sequences are known worldwide, and the majority of fossils from these localities comprise incomplete specimens such as isolated wings and elytra. A single site in the Newark Supergroup of eastern North America has been found to contain numerous complete Late Triassic insects. The Solite Quarry is situated on the Virginia-North Carolina state line, and it has produced the oldest global records for water bugs, thrips and caddisflies. Other fossils found to date include a unique gliding reptile and numerous specimens of a small aquatic reptile that frequently preserve details of their soft part anatomy. These have yet to be fully described. Only a relatively small portion of the fossiliferous sequences has been excavated and PIs will open large-scale excavations in the most productive quarry units. The next phase of the work will be to conduct detailed studies of all the finds and to compare them with the two major assemblages that share the most in common: the Madygen Formation of Kirghizistan and the Molteno Formation of South Africa. The exquisite preservation of the Solite insects will permit a complete re-evaluation of the extensive Russian and South African insect collections and thereby allow for a better understanding of the mode and tempo of insect evolution and radiation at this critical time.For a long time the Solite quarry was regarded as being largely unfossiliferous. Certainly the microscopic insect fossils can be readily overlooked under normal lighting conditions. The search image is critical to the PIs success, and using the same methods they have identified other localities nearby that also contain insect remains. Together with the diverse plant and vertebrate remains, they shall reconstruct a detailed picture of marginal freshwater ecosystems in the Late Triassic.