THE STEINHART AQUARIUM - Gulf of Guinea Science ...

leaves, and each batch is housed in an egg
case made from an abdominal secretion. The
case hardens to protect the eggs from birds,
and other predators. After about a month the
nymphs hatch and then molt several times,
each time becoming more like the adult form.
Mortality/Longevity: Generally a long-lived
species. Molt every 3–5 weeks, until the 4th
and final molting. Life span: up to 14 months
in captivity.
Remarks: The scientific name is probably
derived from Greek for “leaf “(phyllo) and Latin
for “head” (crania), thus “leafy head mantis.”
ORDER COELEOPTERA
(BEETLES)
Sunburst Diving Beetle
Thermonectus marmoratus (Dytiscidae)
Predaceous Diving Beetles
Distribution: Arizona, Southern California,
New Mexico, Western Texas and Mexico.
Habitat: Freshwater rivers, lakes, intermittent
streams, and pools. Because they are winged,
they travel to other areas when their water
source dries up.
Appearance: Bodies are oval and flattened with
smooth contours. Gold markings on the black
carapace and yellow spots on the abdomen
give the species its common name. Females
slightly larger than males. Length: 10–15 mm.
Diet: Small aquatic animals such as mosquito
larvae, water mites, and worms. The beetles
may also eat dead organisms found on the
surface film or the bottom, engulfing small
items and chewing large ones. They have
sometimes been seen swarming a prey item
and feeding en masse.
Reproduction and Development: Diving beetles
undergo complete metamorphosis. Their eggs
are attached to underwater plants and hatch into
the larval stage. Larvae later pupate in mud near
water; and the adult emerges ready to breed a
few weeks late.
Mortality/Longevity: Both adults and larvae are
predators and, with strong sickle-shaped jaws,
can attack prey larger than themselves. They
survive dry periods by burrowing into the mud.
Remarks: With their streamlined body, the
beetle swims effortlessly by flexing its hind
California Academy of Sciences
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legs together simultaneously, and can remain
underwater for a long time breathing air
trapped in a chamber under its wing covers.
Large swarms of these beetles sometimes fly
to artificial lights at night.
When disturbed, they eject a milky fluid which
contains a mixture of steroid compounds,
presumably as a deterrent to fish predators.
They benefit humans because they eat other
invertebrates including mosquito larvae and
pupae.
ORDER LEPIDOPTERA
(BUTTERFLIES AND MOTHS)
Banded Orange
Dryadula phaetusa (Nymphalidae)
Brush-footed Butterflies
Distribution: Native throughout the
continental Neotropics, from central Mexico
to Brazil; summer migrant in U.S. north to
Kansas.
Habitat: Disturbed lowland areas.
Appearance: Males: bright brown and orangestriped
pattern above; striking and quite
different brown, orange, and white pattern
below. Females somewhat duller.
Diet: Caterpillars feed on various host passion
flower vine species; adults feed primarily on
nectar and bird droppings.
Reproduction and Development: Eggs are
laid singly on stems and leaves of host plants.
Mortality/Longevity: Long lived for butterflies
(See Postman).
Remarks: The Banded Orange is the sole member
of its genus. The genus is distinguished by having
shorter, broader wings and shorter antennae than
others in the heliconiine subfamily.
Giant Owl Butterfly
Caligo memnon (Nymphalidae)
Brush-footed Butterflies
Distribution: Mexico south to Amazonia.
Habitat: Rainforests and secondary forests.
Appearance: A very large butterfly: wingspan
up to 12.5 cm.
Diet: Adults feed on rotting fruit, sipping
liquids through their proboscis.
Remarks: Giant owls not always applauded
by human cohabitants. Larvae are large and