''Limnichthys fasciatus'', the barred sand burrower, is a
species of
sandburrower
The sandburrowers or simply burrowers are a family, Creediidae, of fishes in the order Perciformes.
They are native to coastal waters the Indian and Pacific Oceans. They are very small fishes; with the exception of the larger Donaldson's sandbur ...
. It is noted for its highly developed eyes, with a structure similar to the eyes of a
chameleon
Chameleons or chamaeleons (family Chamaeleonidae) are a distinctive and highly specialized clade of Old World lizards with 202 species described as of June 2015. The members of this family are best known for their distinct range of colors, bein ...
, which has led it to be described as marine chameleon.
[Pettigrew, J. D., and S. P. Collin. "Terrestrial optics in an aquatic eye: The sandlance, Limnichthytes fasciatus (Creediidae, Teleostei)." Journal of Comparative Physiology A 177.4 (1995): 397–408.] Its fully grown length measures between and . The species is native to reefs in the
Indo-Pacific
The Indo-Pacific is a vast biogeographic region of Earth.
In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...
. The fish preys on plankton prey by surprise attacking it from a hiding in loose sand,
[Schwab, I. R., S. P. Collin, and J. D. Pettigrew.]
Chameleon of the sea.
British Journal of Ophthalmology 89.1 (2005): 4–4. with only the eyes protruding from the sand.
[Fritsches, Kerstin A., and Justin Marshall. "A new category of eye movements in a small fish." Current Biology 9.8 (1999): R272–R273.]
Vision
A unique property of this species is its vision. The cornea is 1/7th of the thickness of the entire eye, and has a convex shape due to a lens embedded in the cornea.
The cornea can focus, which allows the fish to have depth perception without moving its head. The lens itself is flattened.
Its eye is also notable for its high density of
retinal ganglion cell
A retinal ganglion cell (RGC) is a type of neuron located near the inner surface (the ganglion cell layer) of the retina of the human eye, eye. It receives visual information from photoreceptor cell, photoreceptors via two intermediate neuron typ ...
s compared to other species of fish.
Because of the rapid and accurate attack on prey, it is assumed the fish has good eyesight.
References
External links
''Limnichthys fasciatus'' @ fishesofaustralia.net.au
{{Taxonbar, from=Q2481210
fasciatus
Marine fish of Australia
Fish described in 1904