''Pholidichthys leucotaenia'', commonly known as the convict blenny/goby or the engineer blenny/goby, is a marine fish from the west-central

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five Borders of the oceans, oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is ...

. Despite its common names, it is neither a

blenny Blennies (from the Greek and , mucus, slime) are a diverse clade of ray-finned fish in the suborder Blennioidei of the percomorph order Blenniiformes. They inhabit marine, brackish, and occasionally freshwater habitats, and generally share sim ...

nor a

goby The Gobioidei are a suborder of percomorph fish. Many of these fishes are called gobies. It is by far the largest and most diverse order within the order Gobiiformes, and one of the most diverse groups of ray-finned fish in general. The subord ...

, but is in fact one of two species in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Pholidichthyidae.

Description

A small eel-shaped fish, it can grow up to in length. Juveniles resemble the striped catfish '' Plotosus lineatus'', which is venomous, having a black body with a white dorsal stripe. As they develop, the stripe changes to white convict-style barring or spotting in the adult.

Ecology

''P. leucotaenia'' lives in shallow lagoons and on coastal reefs from the Philippines to the Solomon Islands. It is often found in schools under ledges or around coral heads. These schools swim in such tight formations, they resemble a single organism. Occasionally, the species is found in the aquarium trade, where it is known for disrupting all but the most stable structures. DNA analyses show this species to be neither a blenny nor a goby, but part of a separate fish family, the Pholidichthyidae. In the

Solomon Islands Solomon Islands, also known simply as the Solomons,John Prados, ''Islands of Destiny'', Dutton Caliber, 2012, p,20 and passim is an island country consisting of six major islands and over 1000 smaller islands in Melanesia, part of Oceania, t ...

, researchers under Eugenie Clark found juveniles emerging from holes in the seafloor and adjoining coral reefs. By day, these juveniles swim up to from their home burrows to feed on plankton. At the end of the day, all returned to the burrows, remarkable and unique behaviour for larval fish. Over the course of the first year in captivity, th
engineer goby
fry will gradually change color as it grows up to 1 cm per month. While their young are out feeding, the parents eject mouthfuls of debris from the burrows. In a single day as much as 3 kg (6.6 lb) of sand might be collected and spat out of the hole by the parents.Life by BBC, 2009, pg 64, Research has revealed a maze of tunnels and chambers totaling a length of some 6 m. At night, young fish dangle by their mouths from the roof of the tunnels by thin mucous threads. Adults may grow to almost , but never leave the tunnels to feed. They frequently take in mouthfuls of juveniles and spit them out again. An inspection of adult stomachs showed only a green slime.

References

External links

* {{Taxonbar, from=Q150444 Cichliformes Taxa named by Pieter Bleeker Fish described in 1856