The job of the pivot table is to summarize your source data table based on the criteria you specify in the filter fields (Report Filter, Column Labels, and Row Labels). You can think of it as a very advanced way to arrange and filter your data.
The Limulidae are the only recent family of the order Xiphosura, and contain all four living species of horseshoe crabs: 1  Carcinoscorpius rotundicauda, the mangrove horseshoe crab, found in Southeast Asia. 2  Limulus polyphemus, the Atlantic horseshoe crab, found along the American Atlantic coast and in the Gulf of Mexico.
Horseshoe crabs are a keystone species within the Delaware Bay ecosystem. Description: Horseshoe crabs look like prehistoric crabs. They have a hard exoskeleton, ten walking legs under the shell, spines on the abdomen and a long tail.ost horseshoe crabs will not even make it to the larval stage before being eaten. If the egg survives, the larval horseshoe crab will hatch from the egg after about 2 weeks or more. The larva looks like a very tiny version of an adult horseshoe crab without a tail.