THE STEINHART AQUARIUM - Gulf of Guinea Science ...

irregular patch of flesh that dangles above the
eyes and acts as a lure to attract prey for this
lie-in-wait predator.
Closure of the wide mouth is triggered by
contact with the lure when a fish or other food
item ventures too close. Back-facing teeth that
can be depressed to facilitate passage of large
objects and the fish’s ability to stretch both
the already-huge jaws and the stomach to
enormous size allow ingestion of prey up to
twice as large as this angler’s body!
Clingfish Family
(Gobiesocidae)
Clingfishes
The family totals about 150 species worldwide;
only 2 - the northern kelpfish (Gobiesox
maeandricus) and the kelp clingfish (Rimicola
muscarum) are found in northern California.
Distribution: Mostly inshore fishes found in
tropical and temperate oceans.
Habitat: Bottom-dwelling fishes, typicallt
found on or under rocks or high up in the
kelp. They possess an adhesive disc, partially
formed by the pelvic fins, to cling tightly to
rocks or blades of kelp even in strong currents
or crashing waves.
Appearance: Most species are small, less than
10 cm length. The tapering body has a single,
posteriorly located dorsal fin, fanlike caudal
fin, no spines, and flattened head. Skin is
smooth and scaleless, with a thick layer of
protective mucus. Cryptic coloration.
Diet: Worms, small crabs, other crustaceans.
Reproduction and Development: In mating
the male nudges the female’s belly. If the female
accepts him, the male moves parallel to her and
quivers. Eggs are deposited on stones, algae,
or other bottom material, and usually guarded
by the male. Larvae are planktonic.
Mortality/Longevity: Usually, early maturity
and short life span (about 2 years).
Conservation Status: All rocky shore creatures
are at risk from coastal development and
pollution such as oil spills and agricultural
runoff, as well as careless visitors who can
trample tide pool animals underfoot.
Remarks: Like a number of other bottomdwelling
fishes, clingfish lack swim bladders,
an internal sac used by other fishes to control
their position in the water.
California Academy of Sciences
119
Clingfish can adhere so tightly to a surface that
a rock might be moved some distance by strong
currents with the fish still attached!
ORDER ATHERINIFORMES
Madagascar Rainbowfish
Bedotia madagascariensis (Bedotiidae)
Madagascar Rainbowfishes
Distribution: Madagascar.
Habitat: It lives in shoals of 50–100 individuals
among waterlogged wood in very strongly
flowing water.
Appearance: Maximum size: 9 cm. Metallic
blue and gold base color with small scattered
black spots on the flanks.
Diet: Stomach content analysis reveals diet of
mostly terrestrial insects. Thus dependent on overhead
forest canopy for its insect food supply.
Reproduction and Development: In courtship,
males, display their fins and colors; then male
swims close to female above spawning site,
and the pair propels eggs and sperm onto the
substrate, to which fertilized eggs attach by
adhesive threads. Spawn on rocks and roots as
habitats are often devoid of aquatic vegetation.
Do not guard nest. Depending on temperature,
eggs hatch in about 10 days.
Conservation Status: IUCN: Near threatened.
Threat is mainly from habitat loss and
degradation.
Banded Rainbowfish
Melanotaenia trifasciata (Melanotaeniidae)
Rainbowfishes
Distribution: Northern Territories and
Queensland, Australia.
Habitat: Mainly in small streams and
waterholes in clear to moderately turbid water.
Occurs over rocky or gravel bottoms or in wellvegetated
areas, frequently around submerged
logs and branches.
Appearance: Compressed body; small head.
Males tend to be larger, deeper bodied, and
more intensely colored. A conspicuous blueblack
stripe runs from the snout, through the
eye, and to the caudal fin. Red dorsal and anal
fins edged in black. Length to 11 cm.
Diet: Crustaceans, worms, insects and insect
larvae.