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

北美东部独特的晚三叠世淡水生态系统的昆虫和脊椎动物群

• 批准号: 0106309
• 负责人: Nicholas Fraser
• 金额: $ 22.93万
• 依托单位: Virginia Museum of Natural History Foundation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-08-01 至 2005-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0106309&HistoricalAwards=false
• 关键词: Insect; Vertebrate; Faunas; Unique; Late

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.

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群Nicholas C. Fraser 和 David A. GrimaldiEAR-0106309 三叠纪末期（230 -200 mya）是现代陆地生态系统演化的关键时期。全球有关于四足动物的良好记录，包括最早的哺乳动物、鳄鱼、海龟、两栖动物（青蛙和蝾螈）、蝶形动物，以及它们的姊妹类群蜥蜴。相比之下，现代动物中最重要的一类昆虫——昆虫的记录则要差得多。全世界已知的产虫丰富的三叠纪序列中只有少数，而且这些地区的大多数化石都是不完整的标本，例如孤立的翅膀和鞘翅。北美洲东部纽瓦克超群的一个地点被发现含有许多完整的晚三叠世昆虫。索利特采石场位于弗吉尼亚州和北卡罗来纳州交界处，这里记录了全球最古老的水蝽、蓟马和石蛾的记录。迄今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样本，这些爬行动物经常保留其软体解剖结构的细节。这些尚未得到充分描述。仅挖掘了相对较小部分的含化石序列，PI 将在生产力最高的采石场进行大规模挖掘。下一阶段的工作将对所有发现进行详细研究，并将它们与两个最有共同点的主要组合进行比较：吉尔吉斯斯坦的 Madygen 地层和南非的 Molteno 地层。对 Solite 昆虫的精心保存将允许对俄罗斯和南非广泛的昆虫收藏进行全面的重新评估，从而更好地了解昆虫在这一关键时期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没有化石。当然，在正常照明条件下，微小的昆虫化石很容易被忽视。搜索图像对于 PI 的成功至关重要，他们使用相同的方法识别了附近也含有昆虫遗骸的其他地点。与多样化的植物和脊椎动物遗骸一起，他们将重建晚三叠世边缘淡水生态系统的详细图景。