also called hockey-stick fish apparently, although I've never seen one sold as that! I used to have an old aquarium book written by one of the original UK fish importers, and apparently these got the name penguinfish because the secretary of their company exclaimed "oh they look like little penguins!" when they first came in - so that's what they sold them as and the name stuck.
I haven't come across that story before, but I guess that it's silly enough to be true. The only species that I've heard called a hockey-stick fish is Nannostomus eques. Alan
Pencilfish and hockey sticks are both names I've heared before but as said Penguinfish was new to me but... nice and funny story !
It's only just struck me that the reasons they might remind someone of penguins are that they are basically black and white and that they usually swim with their bodies angled upwards, which is made more obvious by the slanting black stripe - but it's still an odd name. Alan