What Is the Smallest Fish?
Minnows may be considered small, but the dwarf pygmy goby, or Pandaka pygmaea is much smaller. In fact, it is the world’s smallest known adult fish. This tiny occupant of the lakes and streams of the Philippines hardly ever grows longer than one-half inch (1.3 centimeters).
Adult males of this tiny freshwater species are typically less than half an inch in length, while adult females can reach a little over a half-inch long. Although this diminutive fish was originally discovered in the Philippines, due to polluted rivers it is suspected to have gone extinct in this country.
In addition to its tiny size, the dwarf pygmy goby can be identified by its pigment less, nearly transparent body with four elongated dark brown spots along each side, along with smaller brown spots dotting its face and back. It also has dark brown pigmentation on its two dorsal fins and at the base of its tail, although its two ventral fins have no pigmentation.
As small as they are, pygmy gobies are a vital part of the marine life cycle in the lakes and streams they inhabit. They get food energy and other nutrients by eating small plants and animals. Later, many gobies are eaten by bigger animals that absorb some of the energy and nutrients.
This species was originally discovered in 1927 in the Malabon River in the Rizal Province of Luzon in the Philippines. However, thanks to reclamation and river pollution, it is currently believed to have died out in this country. It can still be found in the wild in parts of Indonesia including Bali and Sulawesi, and has also been spotted in Singapore. Sightings have also been reported in Fiji and Papua New Guinea.
As a freshwater fish, the dwarf pygmy goby inhabits brackish waters, usually in rivers with soft muddy bottoms and aquatic vegetation. It is also found in mangrove forests. Plankton serves as its main food source. Between this species being a fairly recent discovery and its low population numbers, not much more is known about its behavior.