376
Appendix 4
Use the general descriptions found in (1) and (2) below to determine the proper
"starting key."
1. Nonarthropods- Use Key A (no jointed legs)
2. Arthropods Gointed legs present)
a. Crustacea-Use Key B (page 377)
(possess gills; biramous appendages; 2 pairs of antennae)
b. Hydracarina (water mites)-further identification difficult
[see Edmondson (1959)] (4 pairs of legs; no antennae)
c. Adult insect-Use Key C (page 377)
[3 pairs of legs; no gills; less than 2 pairs of antennae; usually with obvious flying
wings which may be under a hard or leathery cover (Collembola are wingless);
body entirely covered with hardened material (chitinous exoskeleton)]
d. Insect naiads-Use Key D (page 378)
(appear much like an adult insect but wingless-developing wing buds often
apparent; body covering and form like adult; abdomen never soft and
membranous)
e. Insect larvae-Use Key E (page 378)
(little or no resemblance to an adult insect; jointed legs, temporary non-jointed
legs or no legs; iflegless, body divided into about 13 segments; much of body soft
and with membranous surface)
Key A: Key to some common freshwater animal phyla
La. Minute to microscopic in size; bodies not divided into cells; solitary or colonial;
sedentary or motile. . . . . . . . . . . . . . . . . . . . . . . . . Phylum Protozoa
1.b. Bodies divided into cells ....... Subkingdom Metazoa . . . . . . . . . . . . . . . 2
2.a. Body with many segments (always more than 13; insect larvae are wormlike
but have only 13 body segments), or unsegmented but with obvious
calcareous shell . . . . . . . . . . . . . . . . . .
. 3
2.b. Body unsegmented and without a true shell . . . . . . . . . . . . . . . . . 4
3.a. Body wormlike; segmented, with setae on segments . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Phylum Annelida (worms)
3.b. Body unsegmented, in or under a hard shell . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . .
. Phylum Mollusca (mussels and snails)
4.a. Body of variable shape. . . . . . . . . . . . . . . . . . . . . . . . . . .. 5
4.b. Body wormlike. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 9
5.a. Sessile, mostly encrusting or mat forming in habit, or gelatinous colonial
forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5.b. Sessile or motile; usually not encrusting . . . . . . . . . . . . . . . . . . . . . . . 7
6.a. Body permeated with pores; no protruding microscopic tentacles; internal
spicules; spongy to touch and often green. . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . Phylum Porifera (freshwater sponges)
6.b. Body enclosed in gelatinous, calcareous or chitinous covering; anterior end
with ciliated tentacles on fold of body wall surrounding mouth. . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . Phylum Bryozoa (moss animals)
7.a. Sessile or planktonic; if sessile, then solitary or colonial; small, stalked form with
mouth surrounded by nonciliated tentacles; if planktonic, then solitary, small,
Appendix 4
Use the general descriptions found in (1) and (2) below to determine the proper
"starting key."
1. Nonarthropods- Use Key A (no jointed legs)
2. Arthropods Gointed legs present)
a. Crustacea-Use Key B (page 377)
(possess gills; biramous appendages; 2 pairs of antennae)
b. Hydracarina (water mites)-further identification difficult
[see Edmondson (1959)] (4 pairs of legs; no antennae)
c. Adult insect-Use Key C (page 377)
[3 pairs of legs; no gills; less than 2 pairs of antennae; usually with obvious flying
wings which may be under a hard or leathery cover (Collembola are wingless);
body entirely covered with hardened material (chitinous exoskeleton)]
d. Insect naiads-Use Key D (page 378)
(appear much like an adult insect but wingless-developing wing buds often
apparent; body covering and form like adult; abdomen never soft and
membranous)
e. Insect larvae-Use Key E (page 378)
(little or no resemblance to an adult insect; jointed legs, temporary non-jointed
legs or no legs; iflegless, body divided into about 13 segments; much of body soft
and with membranous surface)
Key A: Key to some common freshwater animal phyla
La. Minute to microscopic in size; bodies not divided into cells; solitary or colonial;
sedentary or motile. . . . . . . . . . . . . . . . . . . . . . . . . Phylum Protozoa
1.b. Bodies divided into cells ....... Subkingdom Metazoa . . . . . . . . . . . . . . . 2
2.a. Body with many segments (always more than 13; insect larvae are wormlike
but have only 13 body segments), or unsegmented but with obvious
calcareous shell . . . . . . . . . . . . . . . . . .
. 3
2.b. Body unsegmented and without a true shell . . . . . . . . . . . . . . . . . 4
3.a. Body wormlike; segmented, with setae on segments . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Phylum Annelida (worms)
3.b. Body unsegmented, in or under a hard shell . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . .
. Phylum Mollusca (mussels and snails)
4.a. Body of variable shape. . . . . . . . . . . . . . . . . . . . . . . . . . .. 5
4.b. Body wormlike. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 9
5.a. Sessile, mostly encrusting or mat forming in habit, or gelatinous colonial
forms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5.b. Sessile or motile; usually not encrusting . . . . . . . . . . . . . . . . . . . . . . . 7
6.a. Body permeated with pores; no protruding microscopic tentacles; internal
spicules; spongy to touch and often green. . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . Phylum Porifera (freshwater sponges)
6.b. Body enclosed in gelatinous, calcareous or chitinous covering; anterior end
with ciliated tentacles on fold of body wall surrounding mouth. . . . . .
. . . . . . . . . . . . . . . . . . . . . . . . Phylum Bryozoa (moss animals)
7.a. Sessile or planktonic; if sessile, then solitary or colonial; small, stalked form with
mouth surrounded by nonciliated tentacles; if planktonic, then solitary, small,