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Insects and Crustaceans: Phylum Arthropoda

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Phylum Arthropoda
Arthropods are animals with a segmented body, external skeleton, and jointed appendages. The Arthropoda includes insects and crustaceans. Only two groups of arthropods are common as fossils in the Cretaceous of the C&D Canal area, and both are types of crustaceans: the Malacostraca (crabs, lobsters, and shrimp) and the microscopic Ostracoda.

The most common crustacean fossils come from the ghost shrimp Callianassa. Pieces of the claws and pinchers are the most common body parts found; only around the area of the Deep Cut have complete appendages been found. More common than body parts are the burrows of this shrimp, which occur as lumpy tubes called called Ophiomorpha nodosa. These "trace fossils" are very common in the Englishtown and Marshalltown formations.

Occasionally, small crabs (Tetracarcinus subquadratus) or fragments of lobsters (Hoploparia gabbi) are found on some of the spoil areas from the Merchantville and Marshalltown Formations.

Ostracodes can be collected by studying the sand-sized residue from screenings of the Mount Laurel Formation.

Reference(s): 

Unless otherwise noted, photographs and figures are from DGS Special Publication No. 18, by E. M. Lauginiger, 1988.

Photo Gallery
10. Callianassa mortoni - specimen from the Merchantville Formation, also occurs in the Mount Laurel Formation and the Marshalltown Formation<br>11. Hoploparia gabbi - specimen from the Merchantville Formation, also occurs in the Marshalltown Formation<br>12. Callianassa mortoni - specimen from the Merchantville Formation, also occurs in the Mount Laurel Formation and the Marshalltown Formation<br>Plus More
Callianassa mortoni - occurs in the Mount Laurel Formation, the Marshalltown Formation, and the Merchantville Formation<br>Tetracarcinus subquadratus - occurs in the Marshalltown Formation and the Merchantville Formation<br>Ophiomorpha nodosa - occurs in the Mount Laurel Formation, the Marshalltown Formation, and the Englishtown Formation<br>Hoploparia gabbi - occurs in the Marshalltown Formation and the Merchantville Formation<br>Plus More
3, 4. Callianassa mortoni - specimens from the Merchantville Formation, also occur in the Mount Laurel Formation and the Marshalltown Formation<br>Photograph from Plate V, DGS Report of Investigations No. 21, by T. E. Pickett, 1972.
7. Ophiomorpha nodosa - specimen from the Englishtown Formation, also occurs in the Mount Laurel Formation and the Marshalltown Formation<br>8. Thalassinoides sp. - specimen from the Marshalltown Formation?<br>Photograph from Plate V, DGS Report of Investigations No. 21, by T. E. Pickett, 1972.