| Popis: |
Thalassinidean shrimp constitute six or seven families of highly specialized burrowing decapod crustaceans. Adaptations to a deep infaunal mode of life, exemplified by the ghost shrimps Callichirus and Callianassa, include an elongate subcylindrical body differentially sclerotized and divided into units functional for life in tubular burrows (i.e., burrowing, locomotion, flexion, pumping, and sealing). Death or molting within burrows may lead to positive biases of preservation of the more heavily sclerotized parts consisting of burrow buttons preserving chelipeds, anterior cephalothoracic regions, posterior abdomen, and walking legs. Thalassinidean chelipeds, particularly the fingers, are among the most common of decapod crustacean body fossils. Illustrations and examples are given to document the full range of fossil remains, including body fossils and trace fossils. An exceptional whole-body thalassinid, Axiopsis eximia, was described by Kensley and Williams (1990) from the Middle Eocene of South Carolina. The specimen is a silicified body fossil preserving virtually the entire animal except distal appendages. This specimen remains the only described silicified thalassinid. This paper is presented as a tribute to Brian Kensley and as closure for the Bishop-Williams collaborations spanning 25 years. |
