Extant Chiloscyllium punctatum (Brownbanded Bamboo Shark) jaws

[MarcoSr]

Here are two jaws that I recently acquired. One jaw is 2.75 inches wide 1.75 inches high. The other is 3.25 inches wide 2.25 inches high. They both were sold as Chiloscyllium jaws, one as a Chiloscyllium punctatum (Brownbanded Bamboo Shark) jaw from Thailand and the other as only Chiloscyllium sp. (Bamboo Shark) jaw from the Philippines. According to Cappetta 2012 Chiloscyllium punctatum are devoid of lateral cusplets like the teeth in these jaws. The lower teeth in both of these jaws reasonably match a line drawing sketch of a lower female antero-lateral Chiloscyllium punctatum tooth in Cappetta 2012. However, because extant shark species are named based upon physical characteristics instead of jaws and teeth, I have not been able to find sufficient reference materials on Chiloscyllium to verify 100% the species of these jaws. However, when you see the pictures below, you will see that there is a very similar tooth morphology between the jaws. Here are the overall jaws:

To better see tooth details double clique the below pictures. If you mouse over the pictures you will see the file name which has additional positional information.

Upper jaw symphysis:

Lower jaw symphysis:

I can’t find any reference that states that Chiloscyllium have medial teeth in the symphysis. Medial teeth are defined (definition from Compagno, 1988) as: small, often symmetrical but may be asymmetrical and occur at the juncture of the left and right jaws. Both of these jaws have a medial file of regular sized teeth that run down the middle of the symphysis of the lower jaw and then have an equal number of tooth files both left and right.

Lower jaw medial tooth file (red):

Continued in the next reply:

Marco Sr.

[MarcoSr]

Cappetta 2012 discuses both anterior and antero-lateral teeth in Chiloscyllium punctatum. However, I am not going to try to name positions of these teeth in these two jaws because I do not have adequate reference material to completely distinguish them and there isn’t a lot of noticeable positional variation among them in these jaws.

Upper jaw left and right side teeth:

Lower jaw left and right side teeth:

Continued in the next reply:

Marco Sr.

Edited January 21, 2016 by MarcoSr

[MarcoSr]

Here are pictures that show the number of rows of teeth in this jaw:

Jaw1: I can see at least 7 upper rows of teeth:

Jaw1: I can see 7 rows of lower teeth:

Jaw2: I can see at least 7 upper rows of teeth:

Jaw2: I can see 9 rows of lower teeth :

The number of files of teeth in a jaw of some shark species can be quite variable. In some species as the shark grows it adds files of teeth. Note that the larger Chiloscyllium jaw2 has an additional file of teeth over Chiloscyllium jaw1.

Jaw1: The upper jaw has 15 tooth files left and 15 tooth files right of the symphysis.

Jaw1: The lower jaw has 15 tooth files left and 15 tooth files right of the medial file.

Jaw2: The upper jaw has 16 tooth files left and 16 tooth files right of the symphysis.

Jaw2: The lower jaw has 16 tooth files left and 16 tooth files right of the medial file.

Cappetta suggests heterogeneity for the Chiloscyllium genus. Therefore, to get a complete feel for Chiloscyllium jaws and teeth you would really need to look at a lot of different jaws from different localities.

Marco Sr.

Edited January 21, 2016 by MarcoSr