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Mackerel (Cretalamna “appendiculata” aka Cretolamna “appendiculata“)

Age – Late Cretaceous; Commonality – Common (slightly less common than Archaeolamna); Size – average: a little under ¾ inch, max: 1 inch (in our area)

These teeth are similar to the teeth of Archaeolamna. The main differences are in the cusplets and the lingual protuberance. The cusplets are scalloped and lower, especially in anterior teeth. The lingual protuberance is reduced and the whole tooth is a little more flattened compared to Archaeolamna. There are many Cretalamna species represented in New Jersey. Referring all of them to the species appendiculata is likely wrong (even though that is the trend among NJ collectors), especially when appendiculata is strictly a Turonian species. Quotations around “appendiculata” are necessary as it is a paleobucket (a species name that is used to group many indeterminate/undescribed species under). cf. Cretalamna biauriculata maroccana is an example of another Cretalamna type of tooth that can be found (although much more rarely). The teeth pictured below are the “common” type.

Anterior Teeth

This is a large lower anterior (likely an a2) tooth. It has some very reduced cusplets in comparison to its cusp size. It also has an interesting indentation on the lingual side of the root (above the cusplet at the right when looking at the lingual side of the root with the root at the top). I suspect this relatively narrow and deep indentation could be from the shark biting its own tooth after it was shed.

This tooth is another lower anterior (likely an a3). It has relatively larger root lobes and lingual protuberance and a shorter and stouter crown than the tooth above.

This tooth is a juvenile lower anterior C. appendiculata. It has quite a different morphology when compared to an adult anterior tooth. Its cusplets are larger compared to its overall size and look similar to the sharp, pointed cusplets on an A. kopingensis.

Lateral Teeth

This is a C. appendiculata upper lateral tooth. Lateral teeth have a more distally slanted crown and relatively wider root. Lateral teeth are generally more common than anteriors; this is because C. appendiculata possessed many more lateral tooth files than anterior tooth files (like most sharks).

This lower lateral tooth has a different form than the lateral tooth above. This is because it is from a different lateral tooth file from the shark’s dentition.

This upper lateral has some labial wrinkles on its crown. C. appendiculata teeth usually have a smooth crown surface. This tooth also has a nice orange color which is uncommon.

Posterior Teeth

Posterior C. appendiculata teeth are reduced in size in comparison to anteriors and laterals (although not as reduced in size as posterior A. kopingensis teeth). They are even more slanted distally and have an even greater relative width compared to laterals. This upper posterior has an interesting root variation. The sides of the root along with the cusplets are bent toward the lingual face of the tooth. This feature can be observed in occlusal view.

This is a small posterior tooth (likely an upper). It likely came from a juvenile or a sub-adult. It seems like C. appendiculata possessed no or very few (1 or 2) lower posterior files. Most posterior teeth are uppers.

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