The Eocene Nanjemoy Formation crops out on the Maryland and Virginia Coastal Plain, along the eastern coast of the United States. This formation is composed of sands, silts and clays and is divided into the Potapaco and Woodstock members. Remains of fishes, reptiles, birds, mammals, molluscs, fruits and seeds are common in the Potapaco Member, in addition to vertebrate coprolites. Here, we present an analysis of more than 2000 coprolites from the Fisher/Sullivan Site in Virginia. The chemical composition (phosphatic) and the type of inclusions (fish bones) indicate that only scats of carnivorous animals were preserved. The analysed specimens were grouped into six morphotypes: (1) the cylindrical morphotype is a cylinder with rounded ends; (2) the segmented morphotype is a cylinder segmented with rounded ends, and occasionally one end is concave; (3) the oval morphotype represents a bean‐shaped coprolite; (4) the scroll morphotype is cylindrical to conical in lateral view and has coils seen only at the ends; (5) the folded morphotype is a spiral that is concentrically folded; and (6) the sinuous morphotype is serpentine, with rounded ends. Coprophagy‐related scrape traces occur in different morphotypes and represent both invertebrate burrows and bite traces made by fishes. The mineralogical and chemical analyses indicate an early precipitation of phosphate and pyrite minerals, probably induced by the microbial community. All coprolites at the Fisher/Sullivan Site were produced by fishes: carcharhiniform sharks for the scroll morphotype and lamniform sharks, probably the genus Carcharias, for the folded morphotype; the oval, cylindrical and segmented morphotypes were likely produced by actinopterygian fishes.

中文翻译：

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美国弗吉尼亚州下始新世Nanjemoy组浅海沉积物中的共生质

始新世Nanjemoy组在美国东部沿海的马里兰和弗吉尼亚沿海平原上生长。该地层由沙子，粉砂和粘土组成，分为Potapaco和Woodstock成员。除脊椎动物共腐殖质外，鱼，爬行动物，鸟类，哺乳动物，软体动物，水果和种子的残留物在波塔帕科成员中很常见。在这里，我们对来自弗吉尼亚州Fisher / Sullivan站点的2000多种proprolites进行了分析。化学成分（磷酸盐）和内含物的类型（鱼骨头）表明只保留了食肉动物的粪便。被分析的标本被分为六种形态：（1）圆柱形态是具有圆形末端的圆柱体。（2）分段形态是一个圆柱体，其端部是圆形的，偶尔一端是凹的。（3）椭圆形代表豆形共prolite；（4）涡旋形态在侧视图中是圆柱形到圆锥形的，并且仅在端部具有线圈。（5）折叠形态是同心折叠的螺旋状。（6）蜿蜒的形态是蛇形的，末端是圆形的。与腐殖病有关的scrap痕迹有不同的形态型，既代表无脊椎动物洞穴，又代表鱼类的叮咬痕迹。矿物学和化学分析表明，可能是微生物群落引起的磷酸盐和黄铁矿矿物的早期沉淀。费舍尔/沙利文站点上的所有副proprolites都是由鱼类生产的：涡旋形态的鲨鱼状鲨鱼和层状鲨鱼（可能是鲨鱼属）（4）涡旋形态在侧视图中是圆柱形到圆锥形的，并且仅在端部具有线圈。（5）折叠形态是同心折叠的螺旋状。（6）蜿蜒的形态是蛇形的，末端是圆形的。与腐殖病有关的scrap痕迹有不同的形态型，既代表无脊椎动物洞穴，又代表鱼类的叮咬痕迹。矿物学和化学分析表明，可能是微生物群落引起的磷酸盐和黄铁矿矿物的早期沉淀。费舍尔/沙利文站点上的所有副proprolites都是由鱼类生产的：涡旋形态的鲨鱼状鲨鱼和层状鲨鱼（可能是鲨鱼属）（4）涡旋形态在侧视图中是圆柱形到圆锥形的，并且仅在端部具有线圈。（5）折叠形态是同心折叠的螺旋状。（6）蜿蜒的形态是蛇形的，末端是圆形的。与腐殖病有关的scrap痕迹有不同的形态型，既代表无脊椎动物洞穴，又代表鱼类的叮咬痕迹。矿物学和化学分析表明，可能是微生物群落引起的磷酸盐和黄铁矿矿物的早期沉淀。费舍尔/沙利文站点上的所有副proprolites都是由鱼类生产的：涡旋形态的鲨鱼状鲨鱼和层状鲨鱼（可能是鲨鱼属）带有圆形末端。与腐殖病有关的scrap痕迹有不同的形态型，既代表无脊椎动物洞穴，又代表鱼类的叮咬痕迹。矿物学和化学分析表明，可能是微生物群落引起的磷酸盐和黄铁矿矿物的早期沉淀。费舍尔/沙利文站点上的所有副proprolites都是由鱼类生产的：涡旋形态的鲨鱼状鲨鱼和层状鲨鱼（可能是鲨鱼属）带有圆形末端。与腐殖病有关的scrap痕迹有不同的形态型，既代表无脊椎动物洞穴，又代表鱼类的叮咬痕迹。矿物学和化学分析表明，可能是微生物群落引起的磷酸盐和黄铁矿矿物的早期沉淀。费舍尔/沙利文站点上的所有副proprolites都是由鱼类生产的：涡旋形态的鲨鱼状鲨鱼和层状鲨鱼（可能是鲨鱼属）char虫，为折叠形态；放线翅目鱼类可能产生椭圆形，圆柱形和分段的形态型。