Three Fin Blenny ( Tripterygion tripteronotus )

/ / Fish

Description

T. tripteronotus grow to a maximum length of 7cm (1). They exhibit sexual dimorphism; the males have a black coloured head, and a bright red body, whereas the female are grey-brown with five dark longitudinal bands (1).

There are only three species of the genus Tripterygion. The other two species are Triptergion melanurus and Tripterygion delaisi.  T. melanurus is also endemic to the Mediterranean.

Habitat

T. tripteronotus usually inhabit depths of up to 6m but can be found down to 12m (1).; they prefer light-exposed and shadowy biotopes particularly between 0 and 3 m (4).

Life Cycle

As with all Tripterygion sp. they are territorial breeders with the males responsible for parental care of the eggs (3).  The territorial males defend an area approximately 1m2 in size; the nest site is located within this area and is about 20 x 20 cm2 (1).  The males attract the gravid females by courtship displays and their bright colour; this results in the initiation of spawning.  Algae in the nest is used as a base to attach the eggs one at a time.  The males fertilise the eggs and exhibit trembling motions whilst being alongside the female as she attaches the eggs to the algae (1).

Unlike the non-territorial males of T. delaisi, the small non-territorial males of T. tripternotus exhibit sneaking behaviour.  T. tripteronotus males have larger gonads and a greater density of nest sites as well as greater competition for nest sites than T. delaisi (1). The nests of T. tripteronotus are only found to depths of 6m because of the light-reflecting properties of the males decrease with depth (4).

Distribution

T. tripteronotus is found throughout the Mediterranean and Black Sea (5).

Behaviour

T. tripteronotus is a non-migratory, territorial species that exhibits homing behaviour (2).

Food

T. tripteronotus feed on benthic invertebrates (5).

Conservation status

Not evaluated under the IUCN Redlist (6)

References

Description written by Nikkita Lawton (2009)

(1) De Jonge, J. and Videler, J. J. (1989).  Differences between the reproductive biologies of Tripterygion tripteronotus and T. delaisi (Pisces, Perciformes, Tripterygiidae): the adaptive significance of an alternative mating strategy and a red instead of a yellow nuptial colour. Marine Biology; 100: 1432-1793

(2) Gibson, R.N. (1999). Movement and homing in intertidal fishes. p. 97-125. In M.H. Horn, K.L.M. Martin and M.A. Chotkowski (eds.)  Intertidal fishes: life in two worlds. Academic Press. 399 p.

(3) Dominques, V. S., Almada, V. C., Santos, R. S., Brito, A., Bernardi G. (2007).  Phylogeography and evolution of the triplefin Tripterygion delaisi (Pisces, Blennioidei).  Marine Biology; 150: 509-519

(4) Carreras-Carbonell, J., Macpherson, E. and Pascual, M. (2005).  Rapid radiation and cryptic speciation in mediterranean triplefin blennies (Pisces: Tripterygiidae) combining multiple species.  Molecular Phylogenetics and Evolution; 37: 751-761

(5) Fisbbase Tripterygion tripteronotus.  [Accessed 02 June 2009] http://www.fishbase.gr/Summary/SpeciesSummary.php?id=1778.

(6) IUCN. IUCN Red List. IUCN Red List. [Accessed: 03 June 2009] http://www.iucnredlist.org.