The MM answer was:
(Tong et al. 1997 Polar Biol.; Bicosoeca)
Bicosoecids are non-photosynthetic stramenopiles (see the first diagram in the Chromalveolata post); this one specifically builds itself a lorica, from which it filters the current with it's feathery anterior flagellum. (similar to choanoflagellates in some ways) They also look a bit similar to Chrysophyte Dinobryon (I spelled it right this time! =P), except that Bicosoeca lacks visible plastids. Some Bicosoecids like Pseudobodo and Cafeteria don't bother making loricas, and just anchor themselves to the substrate with one of the flagella. According to Cafeteria's Encyclopedia of Life webpage:
Sometimes taxonomy can be quite humourous!
"As to the source of this name; it was prompted by a pink neon sign affixed to the wall of a hostelry in Roenbjerg (Denmark)which was illuminated just as the authors'were about to give up on finding a good name for one of the most significant consumers in the world."
Despite being fairly common, these little critters are quite understudied, and very little is known about them beyond their basic morphology. Notice a common theme arising among most protist posts? Do something! We don't need THAT many people crowded on the N-terminus of some random mouse 'oncogene' (whatever that means), and there's space here!
I'll try to make next week's Mystery Micrograph a bit easier!