The New Zealand bigeye (''Pempheris adspersa'') is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species. The ray-finned fishes are so called because their fins are webs of skin supported by bony or hor ...

, a

sweeper Sweepers are small, tropical marine (occasionally brackish) perciform fish of the family Pempheridae. Found in the western Atlantic Ocean and Indo-Pacific region, the family contains about 26 species in two genera. One species (''Pempheris xanth ...

from the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Pempheridae Sweepers are small, tropical marine (occasionally brackish) perciform fish of the family Pempheridae. Found in the western Atlantic Ocean and Indo-Pacific region, the family contains about 26 species in two genera. One species (''Pempheris xan ...

. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to the waters around New Zealand. It inhabitants rocky shores with plentiful overhangs and crevices at depths of from near the surface to .

Description

The New Zealand bigeyes has large eyes, as its name suggests and a deeply keeled and compressed body. Its body is dark in colour and is marked all over with small spots. This species can reach a length of SL.

Distribution

The New Zealand bigeye is endemic to the northeastern coast of the

North Island The North Island, also officially named Te Ika-a-Māui, is one of the two main islands of New Zealand, separated from the larger but much less populous South Island by the Cook Strait. The island's area is , making it the world's 14th-largest ...

of New Zealand.

Biology

This species is nocturnal. They feed on plankton and some

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "t ...

organisms. Some groups have been observed to travel well upstream at night to feed on

shrimp Shrimp are crustaceans (a form of shellfish) with elongated bodies and a primarily swimming mode of locomotion – most commonly Caridea and Dendrobranchiata of the decapod order, although some crustaceans outside of this order are refer ...

s, amphipods, crab larvae, and other

zooplankton Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by ...

. During the day, these fish shelter in crevices or caves, or under overhangs and ledges. When they emerge from their shelter at night, they have been found to use vocalisations and popping to maintain social contact within a shoal. They perceive sounds through a specialisation of the

swim bladder The swim bladder, gas bladder, fish maw, or air bladder is an internal gas-filled Organ (anatomy), organ that contributes to the ability of many bony fish (but not cartilaginous fish) to control their buoyancy, and thus to stay at their curren ...

, Baudelot's ligament and their

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial ...

Gravid In biology and human medicine, gravidity and parity are the number of times a woman is or has been pregnant (gravidity) and carried the pregnancies to a viable gestational age (parity). These terms are usually coupled, sometimes with additional te ...

females have been collected from mid-November up until February and spawning has been observed to occur at the same time with the juveniles settling from January to April. Juveniles have been recorded from weed growing along rock shorelines in the late (Austral) summer. The bigeyes have also been recorded swimming into estuaries to feed on

among mangrove forests. It ranges in depth from

References

{{Taxonbar, from=Q2457620 New Zealand bigeye Endemic marine fish of New Zealand Fish described in 1927