Nannoperca pygmaea
Little Pygmy Perch
Species Summary
Described as recently as 2013 from just 15 specimens collected in the Hay River system of south-western Australia, Nannoperca pygmaea has one of the most restricted ranges of any Australian fish — known from an area of only about 0.06 km², mostly a handful of pools. It is listed as Endangered under both the federal Environment Protection and Biodiversity Conservation Act and the Western Australian Biodiversity Conservation Act.
Description
Differs from its close, range-sharing relative the Western Pygmy Perch (Nannoperca vittata) in lacking dark pigment on the ventral surface in front of the anus, in having thin latero-ventral stripes, generally fewer dorsal and anal fin rays, unpigmented scale margins on the caudal peduncle, and a more strongly haloed dark spot at the base of the tail fin. Allozyme analysis confirms Nannoperca pygmaea and N. vittata belong to genetically distinct lineages with no intermediates where they occur together, distinguished by fixed differences at fifteen separate genetic loci.
Compiled for Home of the Rainbowfish from ANGFA sources: D. L. Morgan, S. J. Beatty & M. Adams, “Nannoperca pygmaea, a New Species of Pygmy Perch (Teleostei: Percichthyidae) from Western Australia”, In-Stream 22(6), June 2013, p. 19 (summarising Zootaxa 3637(4): 401–411).