THE STEINHART AQUARIUM - Gulf of Guinea Science ...

and partially pink or salmon-colored hairs..
Max. size: body, 9-10 cm; leg span, 20-25 cm.
Diet: Eat large crawling insects and other
invertebrates, small rodents, lizards, & frogs.
Regardless of its name, the spider is rarely seen
eating birds. However, it does occasionally
attack the newly hatched chicks of grounddwelling
birds. Prey is subdued by venom
injected by chelicerae. Digestive juices are
injected that liquefy the kill, which is then
sucked in by the mouthparts.
Reproduction and Development: This species,
like most tarantulas, is solitary and comes in
contact with others of its species only during
mating. Once sexually mature, the male spins
a small area of silk onto which he deposits his
sperm. The sperm is then absorbed into the
pedipalps, which during mating are inserted into
the reproductive organ of the female, transferring
sperm which can remain viable within the
female. The female lays up to 2000 eggs in a
thick, silken sac, approximately 3 months after
breeding. She will guard this sac fiercely, and
incubation lasts approximately 3 weeks, after
which white spiderlings are born. Young are
voracious feeders. As a result the babies grow
very quickly, up to 15 cm in the first year.
Mortality/Longevity: Tarantulas have few
enemies except the tarantula hawk wasps.
Members of this wasp family use their sting
to paralyze species specific tarantualas. The
wasp lays an egg on the tarantula’s abdomen
and then seals the spider in its burrow. The
wasp larva hatches and feeds on the immobile
and doomed tarantula. Males usually die
shortly after maturity and mating, usually
Females can live up to 15 years in the wild,
perhaps significantly longer. Typically thrive
in captivity 4–8 years.
Conservation Status: Still quite common,
though destruction of the rainforests reduces
natural habitat.
Remarks: Like most tarantulas and some other
spiders, if this spider loses one of its legs, it can
regrow the lost appendage, which begins as a
small stump & then grows more complete with
each molting.
While not highly aggressive and bites are not
fatal to humans, this big bruiser can inflict a
serious wound which one researcher defined
as “capable of medically significant mechanical
California Academy of Sciences
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damage”! Translation: handle with care!
Will become aggressive if threatened.
Though body hairs are most often used to
detect predators and prey by picking up air
movements around the spider, they are also
used as defensive weapons. If pursued by a
potential foe, the spider rubs its legs against
its abdomen, throwing tiny, barbed hairs that
become imbedded in the attacker. The barbs
can cause significant irritation, especially if
lodged in the eyes or nasal passages.
Possible origin of the fanciful name “Bird-
Eating Spider”: In 1705, a Swiss naturalist and
painter, Madame Maria Sibylla Merian, painted
a Dutch Guianan bird-eating spider with a size
ridiculed as a flight of female fancy until 1863
when an English naturalist observed a spider of
similar features and size in the Amazon forest.
Black Widow Spider
Latrodectus mactans (Theridiidae)
Distribution: In the U.S. ranges north to New
England, south to Florida, Texas, Oklahoma;
west to California, and throughout the
southwest deserts. Also found in Canada,
Mexico, the West Indies, and South America.
Habitat: Favors retreats close to the ground,
especially dark, sheltered spots, such as
under stones, in woodpiles, crevices, barns,
and outbuildings. Usually not found indoors.
Appearance: Female is glossy, coal-black color
with long, slender legs and round abdomen;
her underside usually carries a characteristic
red hourglass mark. Larger than the browner
male, the female may grow to about 3.8 cm,
counting legspan.
Diet: Carnivorous, mostly on insects, but
also on other small invertebrates. When prey
becomes ensnared in the web, black widow
wraps it in silken threads and injects venom.
When movement ceases, the spider releases
digestive enzymes that liquefy the flesh of prey.
Reproduction and Development: Female
produces eggs sacs, which she guards until
spiderlings hatch and are wind dispersed.
A single mating provides her with a lifetime
sperm supply. The widespread story that
female’s eat the male after mating is actually
an infrequent occurrence.
Mortality/Longevity: Probably lives, like most
spiders, about one year. Preyed upon by muddauber
wasps.