Ken Schultz's Field Guide to Saltwater Fish - Macaw Pets store

Killifish
Mummichog
Fundulus heteroclitus
Habitat. Killifish travel in
schools, generally in the
shallows, and are an important
link in wetland and
estuarine food webs. They
are important prey for
shorebirds, crabs, and larger
fish, and many species are
valued for mosquito control,
as they feed on the surface
and consume whatever
insect larvae and small
invertebrates are available.
Killifish are also among the
species most tolerant of
high turbidity and low oxygen.
Many killifish live in
brackish water, as well as
freshwater.
116 Killifish
Also called topminnows and toothed carps, these fish are
members of the large Cyprinodontidae family of small fish.
They are most abundant in warm climates, but a few
species occur in temperate regions. The fins are soft rayed,
as in cyprinid minnows, but killifish have scales on their
heads and have no lateral lines. Typical family members
have flattened heads, and the mouths open upward, an
adaptation for feeding at the surface. Some species are used
as bait, and many tropical species are kept in aquariums.
The best known of these is the mummichog (Fundulus
heteroclitus), a robust 3- to 5-inch species found along the
Atlantic coast from Florida to Labrador. It can tolerate salinities
to 35 parts per thousand. The mummichog is noted for
its habit of burrowing into the silt on the bottom, sometimes
to depths of 6 inches or more in winter. On the Pacific
coast, the California killifish (F. parvipinnis) is similar in size
and habits to the mummichog and occupies the same ecological
niche.
Other well-known species include the banded killifish
(F. diaphanus), which occurs from South Carolina northward
to the St. Lawrence River and westward through the
Mississippi Valley, and the gold topminnow (F. chrysotus),
which inhabits freshwater and brackish estuaries and
streams from Florida to South Carolina. Other common
species of Fundulus include the banded topminnow (F. cingulatus),
the striped killifish (F. majalis), and the saltmarsh
topminnow (F. jenkinsi).
Florida has the greatest representation of cyprinodonts in
North America. Notable among these is the flagfish
(Jordanella floridae), a short-bodied, almost sunfishlike
species attaining a maximum length of 3 inches, and the
pygmy killifish (Leptolucania ommata), a slender fish that
rarely exceeds 1 1 ⁄2 inches in length.