... of thinking that my synodontis was nigrita, I finally found out what it is. Its synodontis robbianus. I always wondered why the pictures of nigrita I saw always looked a bit different from my fish. I saw on a site that nigrita and robbianus are commonly confused with each other. A picture can be found here http://species.fishindex.com/photo_138synodontis_robbianus_spotfin_synodontis.html That one looks just about identical to mine.