A new species of leaf fish has been described from Sumatra in a recent issue of the journal Zootaxa.
Heok Hee Ng names the new species, from the Musi River drainage in southern Sumatra, Nandus mercatus.
Nandus mercatus is distinguished from other members of the genus in having a combination of: body depth 43.0"43.2% standard length, 15 pectoral-fin rays, 29"32 lateral line scales, 11"12 scale rows below the lateral line, and a slightly concave predorsal profile.
The stream from which the single paratype was obtained had brown water and was of low pH (4.3).
The name of the new species comes from the Latin for market, and is used in reference to the method with which the holotype was obtained (purchased from a market).
For more information, see the paper: Ng, HH (2008) Nandus mercatus (Teleostei: Perciformes: Nandidae), a new leaf fish from Sumatra. Zootaxa 1963, pp. 43"53.