A Pictographic Key to Leaf Litter Arthropods
Missouri Ozark Forest Ecosystem Project (MOFEP)
PARTS OF THIS PAGE ARE STILL UNDER
CONSTRUCTION. WE HOPE THIS DOES NOT INCONVENIENCE YOU.
SARAH HEYMAN - Department of Biological
Sciences,University of Missouri,
JAN WEAVER -Department of Biological Sciences, University of Missouri,
Role of Leaf Litter Arthropods
In theory, 90% of the biomass produced by a forest returns to the soil. There,
bacteria and fungi break down the leaves and dead wood into nutrients that can be
taken up again by plants to make new leaves and wood. Although the bacteria and
fungi could do this by themselves, it would take a very long time without the
activity of the animals that live in the leaf litter and the first few centimeters
of soil. Mites (related to ticks) and springtails (primitive wingless insects),
whose combined weight may be less than 2 grams per square meter, may recycle almost
30% of the leaves and wood on the forest floor. Indirectly, their feeding breaks
litter into smaller pieces, increasing the surface area where decomposition by
bacteria and fungi actually take place. Their feeding also coats the pieces with
fungal spores and bacteria. Both of these may double or even triple the rate of
decomposition by fungi and bacteria.
The leaf litter animals also play an important role in the forest food web. There is
1 1/2 times as much energy stored in the soil and leaf litter of a forest as there
is in the trees. In addition, the leaf litter animals are very efficient at turning
the food they eat into biomass. As a result they can support long food chains. For
example, a mite will eat dead leaves and fungus, this mite will be eaten by a
predatory mite, the predatory mite will be eaten by a spider, the spider will be
eaten by a beetle, the beetle will be eaten by a mouse, and the mouse will be
eaten by an owl. These long chains are important because they allow important
minerals like sodium and calcium to be concentrated and then used by animals higher
on the food chain.
MOFEP stands for Missouri Ozark Forest Ecosystem Project. This is a long term (100
years), large scale (over 2000 hectares) experimental study of the effects of clear
cutting, selective cutting and no cutting on Ozark forest. This experiment is a
cooperative effort of the Missouri Department of Conservation's (MDC) Forestry and
Wildlife Research units, with the involvement of MDC Natural History SEction, the
U.jS. Forest Service North Central Forest Experiment Station, the University of
Missouri and others.
(If you want to
about MOFEP click
Our study is looking at the community of leaf litter animals
before and after the cutting treatments. To sample this community we set up 36 5
meter x 5 meter plots. Twelve plots are in forest that will be 10% clearcut, 12 are
in forest that will be 10% selectively cut, and 12 are in forest that are not cut.
From each plot we collect 4 samples of leaf litter with an area of 0.02 square
meters (the area of a 3 lb coffee can lid). The leaf litter is dried and heated
under a light bulb and as the animals move down through the litter to avoid the heat
they fall into a collecting container of alcohol. We bring these alcohol containers
back to the lab and sort the animals under the microscope. An average sample may
have 50 species and over 1000 individuals.
Why a Web Page?
In order to describe this community, we need to be able to tell the different
species in the leaf litter apart, and be able to recognize them when we see them
again. Early on in the study we sketched every new species we found, giving it a
unique number and a special identification code. However, as more people became
involved in the project we decided it would be better to take pictures of our
animals and store the pictures on a computer - kind of an electronic catalog of
species. At about the same time, the world wide web was becoming established, so we
decided to put our catalog on the web, so anyone with an interest in these animals
could see what we had found. With the support of the Bay Foundation, the University
of Missouri, and the Missouri Department of Conservation, we purchased a digital
camera, a microscope, and a computer that allowed us to set up this web page.
INTRODUCTION TO THE KEY:
A key is a list of characteristics used to sort animals or
plants into separate groups. If you are not familiar with the
characteristics listed below, we suggest you read a brief introductory
section on them before you try to use the key.
- larva, larvae, or larval
IF ANY OF THESE WORDS
ARE UNFAMILIAR, CLICK HERE FOR AN
ILLUSTRATED INTRODUCTION TO ARTHROPOD ANATOMY.
How to use the key
- To use this key, just click on the highlighted name, characteristic or
picture most similar to the animal you are examining. This will link you to pictures
of other similar animals. Repeat this process until you find a species which looks
- We have included notes to point out distinctive characteristics
and scale bars for reference. All scale bars are 1 millimeter unless otherwise
- When available,we included information about the ecology of the animals
and a list of scientific references.
- While we have organized the key so it is consistent with
current taxonomy, it is not strictly taxonomic. In order to reach a wider
audience, we used easy to spot characteristics and a minimum of technical terms to
describe our specimens.
- Some of our species have not yet been identified, and
are only referred to by the i.d. number they are assigned in our study.
If you have some idea about what something is, please contact us. If
you have a question about our identification, please let us
Categories: Click on a
category if you already have an idea of what you have, otherwise start
- arachnids(spiders, mites,
- hemipterans (true bugs)
- dipterans (flies)
list of general references:
- Bland and Jaques. (1978). How to Know the
Wm. C. Brown Company. Dubuque, IA.
- Coleman and Crossley. (1995). Fundamentals of
Soil Ecology. Academic Press. San Diego, CA.
- Dindal . (1990). Soil Biology Guide. John Wiley
and Sons. New York, NY.
- Borror, D. J., Triplehorn, C. A., and Johnson, N. F. (1989).
to the Study of Insects. (6th Edition) Saunders College Publishing. Philadelphia,
- Romoser and Stoffolano. (1993). The Science of
Entomology. Wm. C. Brown Publishing Co. Dubuque, IA.
Specific resources on individual groups are located at the end of the
This is an original publication produced by Heyman and Weaver, based
on the collection made as part of the Missouri Forest Ecosystem Project
This page was made possible by grants from the Bay Foundation (New York),
the University of Missouri (Columbia) Division of Biological Sciences, and
General Education Program, and the Missouri Department of Conservation.
We would also like to thank Dave Larsen, Ernest Bernard, John Fick,
Bruce Shimel, Alan Marshall and all our beta testers for their
valuable assistance in putting this page together.
©All material is protected by Section 107 of the
1976 copyright law.
Copyright is held by University of Missouri and Sarah Heyman and Jan
All photograpgs and drawings produced by Sarah Heyman and orginal with
this publication. If you intend to use this material or these images,
please acknowledge the authors and the source of the
last modified May 1999.
Suggestions, corrections, and/or comments are appreciated: Contact Jan
The URL for this page is http://www.missouri.edu/~bioscish/index.shtml