Smallest organisms with mature females measuring as little as in standard length. This fish, a member of the carp family, has a translucent body and a head unprotected by a skeleton. The one of world's smallest fish based on the minimum size at maturity is "Schindleria brevipinguis" from Australia,their females reach it at 7 mm (0.28 in) and males at 6.5 mm (0.26 in), Males of "S. brevipinguis" have an average standard length of , a gravid female was . This fish, a member of the goby family,its first anal-fin ray further forward, under dorsal-fin 4. Male individuals of the anglerfish species
Smallest organisms montane environments. There is relatively little data on size variation among individuals, growth from metamorphosis to adulthood or size variation among populations in these species. Additional studies and the discovery of further minute frog species are likely to change the rank order of this list. The dwarf gecko ("Sphaerodactylus ariasae") and the Virgin Islands dwarf sphaero ("S. parthenopion"), two geckos in the genus "Sphaerodactylus", are the world's smallest known reptile species and smallest lizard, with a snout-vent length of . A few "Brookesia" chameleons from Madagascar are equally small, with a reported snout-vent length of 15–18 millimetres for male dwarf