Head spots on Syno's?

[CatBrat]

I recently took these close up pictures of the head of my Polka-dot Syno (Synodontis angelicus). I was wondering if anyboy knows what the tiny white dots that cover (just) the head are. They are barely visible with the naked eye. I have since noticed that they are on my other species of syno's aswell See pic's....





Cheers, CatBrat.

[Silurus]

Those are tubercles. Although seldom reported, mochokids do possess tuberculate skin, especially around the head. These tubercles apparently are more numerous and larger in males, especially during breeding season.
You can also see tubercles on the head of my Euchilichthys (also a mochokid):

[Dinyar]

My impression is that many but not all Synodontis possess granular skin. Cf. Eccles, <Field Guide to the Fishes of Tanzania> (may not be exact reference), which divides Tanzanian Synos into granular and non-granular groups. Perhaps there is always some degree of granulosity on the skin above nuchal plate, but sometimes not elsewhere?

Dinyar

[Silurus]

And the difference between granular and tuberculate being?
Granular is just a less exact way of saying tuberculate.

[Dinyar]

Just a different choice of words, HH.