THE STEINHART AQUARIUM - Gulf of Guinea Science ...

106 A Docent Field Guide to the Species of the Steinhart Aquarium
regions, throughout the year in the tropics.
Polygamous: a spawning female is typically
followed by several males. Fertilization is
external. Female deposits sticky eggs in
shallow vegetation. An average-sized female
can produce about 300,000 eggs in a season.
A larger female can deposit more than one
million eggs per season. Eggs are not guarded,
and hatch after four days.
Mortality/Longevity: Live to 20 years.
Remarks: A highly popular fish in the
commercial trade, also a gamefish.
Romans introduced carp into various locations
in northern and western Europe as a food
fish. Monks in medieval times continued this
“Johnny Appleseed” manner. Thus the native
and introduced habitats of the koi are presently
impossible to tease out.
Koi are a plastic species with a marked
tendency to produce differing varieties
and races in response to selective breeding
and environmental factors. They have been
selectively bred in many areas, especially Japan,
for over 200 years.
Zebra Danio
Danio rerio (Cyprinidae)
Minnows or Carps
Distribution: Indo-Pacific.
Habitat: Streams, canals, ditches, and ponds
as well as rice fields.
Appearance: Named for its five horizontal blue
stripes extending along on the sides of the body
as well as the anal and caudal fins. Grows to 6
cm. Males have gold stripes between the blue
and females have silver.
Diet: Omnivorous. Small aquatic insects, crustaceans,
worms, and plankton.
Reproduction and Development: Egg-scatterers;
produce about 100 eggs in a single spawning.
Breed readily in captivity.
Remarks: Typically a schooling fish. This species
is useful for studies of vertebrate development
and gene function as they reproduce
easily and quickly, developing from egg to
larva in less than 3 days. Zebra danios have
the distinction of being one of the few fishes
to have flown in space. In June, 1976, Salut
5 carried tortoises and a zebra danio (not to
mention cosmonauts)!
Redtail Black Shark
Epalzeorhynchos bicolor (Cyprinidae)
Minnows or Carps
Distribution: Originally from the Mae Klong
River in Thailand.
Habitat: Middle and bottom levels of freshwater
streams and rivers, especially areas with rocks
and/or plants for resting and hiding.
Appearance: A striking fish with deep velvetblack
body and bright red caudal fin. Max.
length: 15 cm.
Diet: Omnivorous, primarily a bottom-feeding
scavenger. (Note the downward facing mouth
with barbels for locating food items and
feeding on soft substrate.)
Reproduction and Development: Spawner,
egg layer.
Mortality/Longevity: Life span: 6–8 years.
Conservation Status: Currently extinct in the
wild, probably due to construction of dams and
draining of swamps rather than overcollecting,
as some suggest. All red-tails available in fish
stores today are commercially raised by the
aquarium trade industry.
Remarks: This fish is aggressive and territorial.
In spite of its common name, most likely
a reference to its streamlined, torpedo shape,
it is not a shark.
Cherry Barb
Puntius titteya (Cyprinidae)
Minnows or Carps
Distribution: Native to Sri Lanka with
introduced populations established in Mexico
and Colombia.
Habitat: Heavily shaded streams and rivulets,
preferring shallow, slow-moving water with
silt substrate and leaf cover.
Appearance: An elongated fish with a
compressed body, fawn-colored on top with
a slight greenish sheen. Sides and belly have
silver highlights with a horizontal stripe
extending from the tip of the snout through
the eye to the base of the caudal fin, with an
iridescent, metallic line above it. Males are
redder than females and attain a deeper red
color at breeding time; females lighter with
yellowish fins. Max. length: 5 cm.
Diet: Omnivorous.
Reproduction and Development: Open water,