THE STEINHART AQUARIUM - Gulf of Guinea Science ...

70 A Docent Field Guide to the Species of the Steinhart Aquarium
Diet: Scavengers on scrapes of decaying tissue
or, when available, the carcasses of dead fish
and invertebrates. Opportunistic “cleaner”
shrimp.
Reproduction and Development: Studied
members of the genus Lysmata, including L.
californica, have been recently shown to be
protandric simultaneous hermaphrodites,
a long name that describes a most unusual
reproductive system. Juveniles first mature and
reproduce as males (thus the “protandric”), but
later attain the female sexual function as well
(thus “hermaphoditic”). Put any two Lysmata
shrimp in a tank and don’t worry if you have a
sexual pair: you do! Each is able to inseminate
the other, and each is able to lay and brood eggs
(thus “simultaneous”). No self-fertilization has
been observed. Whatever works!
Remarks: Red rock shrimp often share
crevices with and act as cleaners to moray
eels. According to one source: “They are also
known to perform cleaning activities on divers’
hands when placed in their vicinity, paying
particular attention to areas around fingernails
or scratches on the skin.”
A small commercial fishery exists for these
shrimp as they are considered choice bait
for recreational anglers of many fish species,
such as opaleye, rubberlip surfperch, and
pile perch.
The species may be moving northward,
perhaps due to climate change, as they have
been found seasonally for more than 20
years in the open ocean filter housing of the
Monterey Bay Aquarium.
Fire Shrimp
Lysmata debelius (Hippolytidae)
Distribution: Indo-Pacific.
Habitat: Coral reefs, in or near overhangs or
caves.
Appearance: Carapace bright red with white
spots. Lower legs and antennae white. Max.
size: 5 cm.
Diet: In the wild, the fire shrimp is primarily
a cleaner, setting up cleaning stations on the
reef. In an aquarium setting, they often feed on
algae or scavenge and forego their cleaner role.
Reproduction and Development: Hermaphroditic.
Any two shrimp make a pair! (See L.
californica)
Mortality/Longevity: Life span: about 4 years
in captivity.
Remarks: Usually live in pairs, aggressively
defending their territory.
Commensal Shrimp aka Sexy Shrimp
Thor amboinensis (Hippolytidae)
Distribution: Common in tropical seas
worldwide.
Habitat: Coral reefs; in association with giant
anemones.
Appearance: Length to 2 cm. This distinctively
colored brown-orange prawn with large white
spots is a stout shrimp with short legs and
claws. Eyes are white.
Diet: Feeds on scraps missed by its commensal
anemone.
Remarks: Not observed to be a cleaner shrimp.
Some Thor anemone shrimp species may gain
protection by mimicking cleaner shrimps,
which many fishes avoid eating.
The distinctive vertical position and movement
of the abdomen earn this shrimp its common
name of “sexy.”
Harlequin Shrimp
Hymenocera picta (Gnathophyllidae)
Distribution: Along East Africa, the Red Sea,
to Indonesia, south to northern Australia and
as far east as the Galapagos.
Habitat: Hard rocky or coral substrates, with
many hiding places.
Appearance: Pinkish white body color with
splashes of purple-edged pink spots. Stalked
eyes and antennae flattened and leaf-shaped.
Max.size: c. 5 cm.
Diet: This shrimp feeds solely on the tube feet
of sea stars. Nocturnal feeder; uses large claws
to pry sea stars off coral reefs.
Reproduction and Development: Male and
female pairs defend their territory. Females
produce ~1,000 eggs at a time that hatch in
about 18 days. Larvae planktonic.
Remarks: Have been bred successfully in
captivity.
Advice to aquarists: given known feeding
habits, don’t keep these aggressive fellows
close to prized sea stars.
On the up side, H. picta is known to feed on
crown-of-thorns sea stars, so perhaps it should
be considered a reef preservationist!