Brachycarcharias lerichei
Brachycarcharias lerichei
Summary
Brachycarcharias lerichei was an early lamniform shark with a sand-tiger-type feeding apparatus. It formed part of a diverse Palaeogene radiation of sharks equipped with long grasping teeth for capturing mobile prey.
Its slender pointed teeth were better suited to piercing and holding than to crushing hard food. This suggests a diet dominated by fishes and other relatively soft-bodied marine animals, with cephalopods also plausible prey. The dentition would have allowed struggling prey to be retained as it was drawn into the mouth.
Like many fossil sharks, B. lerichei is known mainly from isolated teeth because cartilage rarely fossilises well. Those teeth nevertheless reveal an active predatory animal occupying the mid-level to large-predator part of the early Eocene marine food web.
Quick Identification
Look for: a tall, narrow, smooth-edged central cusp with small pointed lateral cusplets and a deeply divided two-lobed root; compare the crown ornament and cusplet form with Striatolamia and Hypotodus.
Diagnostic Features
- Central cusp is tall, slender and sharply pointed.
- Cutting edges are smooth and continuous, without serration.
- Small lateral cusplets flank the main cusp on complete teeth.
- Lingual crown face is smooth to only weakly ornamented rather than strongly striated.
- Root is strongly bilobed with a pronounced central nutritive area.
Fossil Details
Similar Species
Recorded Fossil Sites
London Clay Formation
Walton Member
References
- Rayner, D.; Mitchell, T.; Rayner, M. (2009). London Clay Fossils of Kent and Essex. 228 pp.. Medway Fossil and Mineral Society, Rochester, Kent View reference
- Ward, D.J. (1980). The distribution of sharks, rays and chimaeroids in the English Palaeogene. Tertiary Research, 3(1), 13–19 View reference