BLENNIES AND GOBIES  (NE Atlantic)

Family:  Blenniidae

The Blennies are a large family of small fish that live on the sea bottom. They are found in coastal waters throughout the world, with a greater variety of species in tropical and warmer seas than around the British Isles. Many species can be found under rocks as the tide recedes. Three of the four species that breed around Britain are listed below.
 
 

BLENNY	TOMPOT BLENNY	MONTAGU'S BLENNY
Shanny, Sea-Frog	Gattorugine	Capuchin
Lipophrys pholis	Parablennius  gattorugine	Corophoblennius galerita
Size:  to 16.5 cm	Size:  to 20 cm, occasionally 30 cm	Size:  to 8.5 cm
Description:	Description:	Description:
Notably lacking lappets on forehead.  Red-rimmed eyes.	Lappets branched  into 2, just above  eyes & between them.	Single lappet on forehead above eyes.
Green with black blotches and dots.  Mature adults, 3 years + are sometimes   grey.	Brown or orange with white/cream   markings give an overall brown aspect.  White mark undet the eye.  Dark blotch between the 2nd and 3rd   tays of the dorsal fin.	Overall green hue with black markings.  Light blue spots on a darker   background.  Row of white spots parallel with the   dorsal fin in the middle of the flanks.
Intertidal:  Feb-Oct for most of its range  All coasts of the British Isles	Sublittoral, occasionally on the shore.  South and west only.	Intertidal:  local south-west and west   only.
Food:  Barnacles, barnacle cirri, crabs,   small crustaceans.	Food:  crabs, worms, sea anemones,   molluscs.	Food: Barnacle cirri, crustaceans.

The other British species is the Butterfly Blenny, Blennius ocellaris. It is usually be found in water deeper than 10 metres off the south-west coast only. It is rarely seen by divers and only occasionally in Public Aquaria. I would be pleased to hear of reports of this fish. Alan Russell has found this fish at extreme low water off the Isle of Man coast. Experienced rockpoolers will not experience any difficulties in separating the three species. The Common Blenny is by far the commonest species between the tides, although Tompots can be quite common in deeper water. However, identification from photographs in some of the poorer natural history books should be treated with caution. Blennies have been mistaken for Gobies (Gobiidae) in popular books. Both families contain small fish, but there should not be any problem differentiating the two families if you get the opportunity of having a close look. The main differences are listed below. Instant identification from just a fleeting glance is not just guesswork. The exact species of blenny presents no difficulty, although it needs a great deal of experience to separate the gobies in the murky shallows.

More information:  Blennies
 
 

BLENNIES	GOBIES
Small elongate fish that lives on the sea bottom.  Lacks a swim bladder.	Small elongate fish that usually lives on the sea bottom.  Lacks a swim bladder.
Mucus covered scaleless skin.	Small scales.
Continuous dorsal fin divided into anterior and posterior.	Two dorsal fins.
Jugular pelvic fin branched into two.	Pelvic fins fused into a sucker-like cup.
Swims poorly with undulating movements across the benthos.	Swims poorly with darting movements across the benthos.
Comb-like teeth for crunching barnacles and crabs	Small teeth suited for swallowing small crustaceans and   worms.
Male guards the eggs	Male guards the eggs

More Information:  Gobies