The world's smallest fish depends on the measurement used.
Based on minimum standard length at maturity the main contenders are Paedocypris progenetica where females can reach it at ,Scholastic news online:The World's Smallest Fish? by: Ezra Billinkoff- Retrieved February 3, 2006Eyepod.org-Worlds Smallest Fish Discovered in Acidic Swamp.New spineless species...These pages are dedicated to explorer Julie "Brook" Thornton Retrieved January 25 the stout infantfish (Schindleria brevipinguis) where females reach it at and males at , and Photocorynus spiniceps where males can reach it at , but are attached to the far larger females. If judging smallest based on the species' maximum size (a measurement often used for fish), Paedocypris progenetica, dwarf pygmy goby (Pandaka pygmaea), midget dwarfgoby (Trimmatom nanus) and the stout infantfish (Schindleria brevipinguis) are not known to exceed in standard length, and the two Leptophilypnion sleeper gobies are less than . A level of uncertainty about the full size range exists for some of these, as only a few specimens have been measured.
Little or no data is available on weight of most of these, but at less than it is likely that the stout infantfish (Schindleria brevipinguis) is the smallest if using this feature.
List of smallest fish in the world ImageCommon name SpeciesFamilyStandard length of smallest known mature individualMaximum known standard lengthDwarf gobyPaedocypris progeneticaCyprinidae, femaleDanionella translucidaCyprinidae10 mm 15 mmDanionella cerebrumCyprinidae10 mm12.6 mmLeptophilypnion fittkauiEleotridae?Leptophilypnion pusillusEleotridae?Dwarf pygmy goby Pandaka pygmaeaGobiidae, maleMidget dwarfgobyTrimmatom nanusGobiidaePhotocorynus spinicepsLinophrynidae, male, female far larger than male and species not among smallest by maximum standard lengthStout infantfishSchindleria brevipinguisGobiidae, maleHyaloglanis pulexTrichomycteridae
See also List of largest fish Smallest organisms
References