Return to Publications List ◄ Next Page►
-23- submarine.
However, some species, such as Thinopictus
pictus LeConte, which burrow in the wet sand in day time and
come out to feed only at night, might be so considered. They should be
investigated for tolerance to total submergence for an extended length of
time. Species, such as those of Cafius,
which are found largely in wrack and which leave the wrack immediately when
it is wetted by sea water, must be called littoral. All inhabitants of salt
marshes should probably be called littoral. Many staphylinids are temporarily attracted to decaying organic material which is not their normal habitat. However, many species are found in masses of seaweed (wrack) which are deposited on the beach with each high tide. The wrack provides food, probably first in the form of entrapped small marine organisms and later in the crustacea and the larvae of flies which soon appear. Staphylinids begin to appear in the wrack as soon as it arrives on the beach only to leave it again if it is wetted once more by salt water. The wrack which is deposited by the highest tide of any tidal period stays on the beach the longest and consequently accumulates the largest population of insects. This period can be as long as 15-20 days. Staphylinids do not breed in the wrack. Few larvae, and those of a few species of Cafius, are even found there. Occasional specimens of staphylinids encountered in the wrack or carrion on the beach should not be included in lists of marine insects if it is suspected that they are only accidental visitors. It is possible that a few such records are in the existing literature. Some records of Fowler (1888) are suspect in this regard, particularly where the insect is also reported from other habitats. It is of interest that the marine
insect fauna of Pacific North America, which extends for a distance north to
south of over 3000 miles from the Aleutian Islands to part of the way down
the coast of Baja California, shows definite correlation with the provinces
outlined or described by marine biologists. Some species of staphylinids, and
of other insects, have a range which encompasses the entire coast. Other
species are restricted to part of the coast. There are at least two regions
on the coast where a partial change in fauna takes place. These are at Point
Conception and near Monterey. This is illustrated in Tables 2 and 3.
Steinbeck and Ricketts (1941) considered the region between Point San
Eugenio, Baja California and Point Conception, California, to be an overlap
area between the Panamic Province and the North Temperate Province. Further
collection of insects along the west coast of Baja California is needed to
substantiate this conjecture. ACKNOWLEDGEMENTS We are pleased to extend our thanks to J.M. Campbell, Saul Frommer, Sam Harter, Melville Hatch, Lee Herman, David Kavanaugh, Horace Last, Hugh B. Leech, Vincent Lee, Helen Moore, Dale Meyerdirk, Robert E. Orth, John Pinto, Vincent Roth, Kohei Sawada and Mary Ann Walsh, all of whom have helped in our study of the marine fauna. |