THE STEINHART AQUARIUM - Gulf of Guinea Science ...

with his dorsal fin fully extended until she
deposits the eggs. The territorial male will then
guard the eggs, which are attached to the walls
of the brood chamber.
Conservation Status: Prolific, not endangered.
Remarks: When threatened, often hides among
the spines of sea urchins.
Barred Mudskipper
Periophthalmus argentilineatus (Gobiidae)
Gobies
Distribution: Indo-Pacific: southern Red Sea
to South Africa, east to Marianas and Samoa,
north to southern Japan, south to western
Australia and Oceania.
Habitat: Brackish mudflats in mangrove areas.
Typically found resting on mud, rocks, or
mangrove roots with its tail dipped in water.
Appearance: Eyes on top of head, mouth
directed downward. Silvery bars on lowers
sides. Strong pectoral fins enable it to lift
its body from the surface and move about.
Partially fused pelvic fins create a suction disk,
a feature common to gobies. Max. size: 15 cm.
Reproduction: Construct deep burrows in
the mud where they sleep and breed. Females
deposit eggs in the burrow and then are
driven out by the male, who tends the eggs
and often aerates them by bringing down
mouthfuls of air that he relases inside the
brooding chamber.
Diet: Worms, crustaceans, insects. Active
predators that sport sharp teeth
Remarks: Actively shuttles back and forth
between rock pools and air.
Amphibious air-breather, the mudskipper is
able to take in oxygen through the skin and
the lining of the mouth and throat, where rich
networks of capillaries absorb oxygen and
release carbon dioxide, rather like a lung. The
animal also has large gill chambers that retain
water, can be tightly closed, and so supply
oxygen to the gills even when the animal is
out of water.
When disturbed, it can jump away from danger
by flipping itself with its muscular pectoral
fins.
The genus name refers to its large and
mobile eyes, peri meaning “all around” (think
periscope, and ophtalmos meaning “eye.”
California Academy of Sciences
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Bluestreak Goby
Valenciennea strigata (Gobiidae)
Sleeper Gobies
Distribution: Indo-Pacific Ocean, East Africa
to Australia, and north to Southern Japan.
Habitat: Shallow reef habitat, usually 1–6
m, but have been found at depths of 25 m.
Commonly seen in clear lagoons over hard
or sandy bottoms, usually in pairs, hovering
around their burrow.
Appearance: Light gray dorsally and white
ventrally with a yellow head; black-edged
blue stripe from the mouth to the rear of the
operculum, a short blue dash behind the eye,
and several curved markings on the lower
sides of the head. Max. length: ~18 cm.
Diet: Benthic invertebrates, fishes, and fish
eggs.
Reproduction and Development: Males
and females bond for life. (The male has
an elongated second dorsal spine that
distinguishes it from the female.) A female
will generally lay about 2000 eggs on the
roof of the nesting chamber. She will tend
the eggs for three weeks, during which
time she will not leave the chamber. Just
before hatching occurs the male will close
the entrance to the chamber, sealing in the
female. After the eggs have hatched, the
male will reopen the chamber, at night,
freeing the 2-millimeter fry.
Remarks: Like many other goby genera,
Valenciennea, commonly called sleeper
gobies, have the habit of resting on the
substrate for long periods. Sleeper gobies,
however, often float motionless just above
the substrate, and so are sometimes called
“hover gobies.”
Members of the genus are carnivorous sandshifters,
a fancy name that describes their
habit of taking in mouthfuls of sand, using
specialized structures in their gills to extract small
invertebrates, and then expelling the sand.
Firefish Goby
Nemateleotris helfrichi (Ptereleotridae)
Dartfishes
Distribution: Central Pacific.
Habitat: Occurs on or near reefs, in relatively
deep water, 25–90 m, over small patches of
sand, rubble, or hard open bottoms of steep