Isn't it less useful than:
- primarily flightless dinosaurs - primarily wingless dinosaurs - primarily featherless dinosaurs - Mesozoic dinosaurs - non-neornithean dinosaurs - extinct dinosaurs (now _that_ is paraphyletic!)
You could find more. You probably will.
Others non-monophyletic group with usefull meaning in some context: *Plant-eater dinosaurs - probably poliphyletic (if incisivosaur and segnosaurs turn out to be really herbivorous theropods). Ex: plant-eater dinosaurs could exhert a great selective pressure on mesozoic flora. *African (North-American, South-American, Chinese, Australian, etc) dinosaurs. Ex: African dinosaurs constitute a fauna quite similar to that of North America during Early Cretaceous time. *Four-legged (two-legged) dinosaurs. Ex: Four-legged dinosaurs evolved independently many times. *Female (male, young) dinosaurs. Ex: Female dinosaurs was probably choosy due to reproductive cost greater then male reproductive cost.
[]s,
Roberto Takata