[Pictured left, from top to bottom: trichopsis pumila (aka “sparkling,” “dwarf,” or “pygmy gourami”); trichopsis schalleri (aka “three stripe gourami”); and trichopsis vittata (aka “croaking gourami”; c/o both Wikipedia and Seriously Fish.]

Trichopsis are a genus of small gourami species native to Southeast Asia. They are popular aquarium fish due to both their iridescent appearance, lively behaviour, and their ability to simulate a clicking or “croaking” noise with their pectoral fins. Based on what I have been able to read, t. schalleri and t. pumila can be differentiated from each other by their size (t. schalleri is slightly larger than t. pumila) and the variable presence of the top horizontal stripe above t. schalleri’s lateral line.