To 4 " (10 cm) usually smaller
There are 2 types . The 3 -Spined and the 9-Spined
3 -Spined .There are 3 forms of this fish depending on the arrangement of Bony Plates on the flank
9-Spined (Pungitius pungitius ) - Altough called 9 - Spined it may in fact possess 7 - 13 Spines !
At spawning time (April - June ) these fish will swim in tight shoals. Care in this fish is interesting as the brightly coloured male builds a spherical nest from plant fragments amongst the vegatation which he will guard . Female lays 80 -100 eggs . Several female fish may lay in one nest and each female may have 5 - 6 broods per season.. Life Span 2 -3 years