biology HW 5/13 & 16/2011

Finish Arthropod survey lab activity- Tiltle;Test; data and observation journal; Analysis and Conclusion questions all into notebook

Arthropod Survey (proto-lab v.1 2011)

Background:

With close to a million named species, the arthropods ("joint-footed animals") make up over three quarters of the animal kingdom; the identifying characteristics of this group that has a rich fossil record dating back to the Precambrian include:

·         Paired, jointed appendages from 1 pair/segment – 2pair/segment – 5 pairs – 8 pair – 6 pairs

·         Segmented body,  with segments often fused into three regions head, thorax and abdomen

·         Chitinous exoskeleton (secreted by underlying epidermis)

·         Ecdysis (molting) of the exoskeleton to allow growth over time

·         Open circulatory system = sinus with contractile heart & arteries = hemocoel; that contains hemolymph = blood

·         Digestive system is  complete (mouth – anus)

·         Nervous system = dorsal brain with 2 ventral nerve cords connecting a chain of ventral ganglia

·         Sense organs are highly developed include: compound eyes, chemoreceptors (smell & taste), vibration (air currents) & tactile (touch) sensing hairs and tympanic organs (hearing)

In terms of reproduction, in most arthropods, the sexes are separate; individuals usually have paired reproductive organs and ducts; fertilization is usually internal, and development often includes metamorphosis.

Materials --Key for identifying classes of arthropods/insect orders, --hand lens, --dissecting scope,

--Berlese funnel, --drop cloths and --collection jars.

Procedures --Arthropod collection

1. Drop cloth collection.  We will go out to the soccer field and employ a drop cloth around vegetation/bush, shake vigorously and transfer specimens into collection jars.  See Procedure 1 day one for collection jar options.
2. Use hand lens/scope and identification keys to complete the data table and identify all the arthropods your group collected by Class; at least 50% of your total identified collection must belong to Class Insecta identified by Order. 
3. Complete both Data Tables and start Analysis & Conclusion questions in class.  Finish at home.

Analysis and Conclusions Students that did work_______________________________________________

1. What characteristics were most useful for determining arthropod Class? Insect Order?  Explain

2. What characteristics were least useful for determining Class/Order?  Explain

3. If you were unsure of one of your classifications, what could you do to make sure of your identification?

4. What ecological roles do the soil arthropods fulfill?  What about the ecological role of the arthropods collected from vegetation?

5. List two ways in which invertebrates are of benefit to humans.

6. List two ways in which invertebrates are harmful to humans.

7. Diagram the external anatomical features of a typical member of O. Orthoptera.

8. Create three bar graphs: 1) Compare the number of representatives for each Class in your survey 2) compare the number of representatives for each insect Order?  3) compare the number of insect Orders represented in the soil vs those collected on vegetation

Data Table for Soil Specimens At least 50% of your specimens must be Insects

# of antennae

# of compound eyes

# of walking legs (per segment/4/5/6)

# of body segments (2/3/more)

Mouth type (siphoning/ sponging/ piercing/ chewing)

# of wings (note: wing covers, halteres or other notable wing characteristics)

Other ID characteristics

Class/Order “Common name” not required

Arthropod Survey Key (proto-lab v.1 2007)

Arthropod Class key

Class Malacostraca (Isopods) are mainly water-inhabiting animals which breathe either by gills or, in the smaller forms, through the surface of the body. In those cases where its members live on land the gills are still present, though in a somewhat modified condition. They have numerous pairs of legs and generally two pairs of antennae (jointed "feelers"). Often some of the body segments are fused with the head to form a cephalothorax.
Class Diplopoda are land animals breathing by air tubes opening on the sides of the body, these tubes carrying the air into all the internal parts of the animal. The head bears a pair of antennae and is followed by a series of segments all practically alike and each, except the first three, with two pairs of legs. The reproductive organs open far forward on the body. In most of the more common members of this group the body is quite cylindrical, and when disturbed the animal usually curls up in a sort of close spiral. The common name "millipede" refers to the large number of legs possessed by these animals.
Class Chilopoda are also land animals like the diplopods they have antennae and breathe by air tubes, and the body segments are practically all alike. The general form, however, is rather flattened; each segment bears only one pair of legs, and the reproductive organs open at the hinder end of the body. The front leg on each side is modified to serve as a poison claw. The numerous legs present in these animals have resulted in their receiving the common name "centipede."
Class Arachnida generally have the segments of the body grouped into two sections called the cephalothorax and abdomen. No antennae are present and the eight legs are all attached to the first body segment.  They breathe by air tubes somewhat similar to those of the other groups; by sacs containing many thin plates resembling leaves of a book, whence these structures take the name of book-lungs; in the smallest forms, directly through the body surface. In the mites there is no evident division of the body into sections.
Class Insecta (aka Hexapoda) the segments of the body are grouped in three distinct sections: the head, thorax and abdomen. A pair of antennae is (with rare exceptions) present on the head; the six legs are attached to the thorax, as are the four wings usually present; the animals breathe by air tubes.

Class Insecta Orders Key

Notes:-

Keys work by a process of elimination, gradually narrowing down the number of possibilities. It is important to understand that a key is much more trustworthy in proving that your insect is not A, than in proving that it is B. It might, for instance, actually be C, a species not mentioned in the key. A key does not prove anything positive, it only suggests possibilities.  The dichotomous key, so-called because at each step it asks you to choose between two alternatives. Thus:

1.  Two pairs of membranous wings...........................................2

Only one pair of membranous wings, the other pair being either hardened into wing-cases, or absent  

                                                                                           ...............29

2.  Fore-wings and hind-wings alike............................................3

     Fore-wings and hind-wings different......................................I8

3.  (and so on).

If the insect agrees with the first alternative of couplet 1, then you proceed to couplet 2; if the first alternative of couplet one is wrong then read the second alternative, if this is correct, then you proceed past all the intervening couplets. Go on like this until you come to a final choice where you will be offered a probable identification:.
Tarsi (singular tarsus) are the last major unit of an insects leg.
Cerci. (singular: cercus) are the paired appendages, often very long, which project from the tip of the abdomen in many insects.   Cerciform tergum = cerci like structures on the dorsal side of the abdomen
Cornicles are the pair of small tubular outgrowths which occur on the hind end of the abdomen of an aphid they, tend to point upwards and backwards from a little way forwards or the tip of the abdomen .

1a. Insect with wings...............................................................................................2

1b. Insect without wings.........................................................................................27

2a. Insects with four wings (two pairs)..................................................................3

2b. Insects with only two wings (one pair)............................................................25

3a. Wings covered with scales...........................................Butterflies and Moths Lepidoptera

3b. Wings not covered with scales, though they may be hairy...........................4

4a. Fore-wings partly or entirely horny or leathery and used as covers for hind-wings often much narrower than hind wings...................................................................................................................5

4b. Both pairs of wings entirely membranous (flexible) and used for flying…12

5a. Mouth-parts tube-like, adapted for piercing and sucking……. True Bugs Hemiptera

5b. Mouth-parts adapted for biting and chewing..................................................6

6a. Fore-wings and hind-wings with veins, hind-wings stiffer and harder than and serving as covers for hind-wings.............................................................................................................................7

6b. Fore-wings without veins, and modified into hard, horny cases for hind-wings  10

7a. Body dorsoventrally flattened.....................................................Cockroaches Orthoptera

7b. Body rounded or quadrate in section................................................................8

8a. Forelegs raptorial, adapted for grasping and holding......Preying Mantids Orthoptera

8b. Forelegs not raptorial...........................................................................................9

9a. Prothorax as large as or larger than meso and meta thorax, hind legs generally enlarged and adapted for jumping........................................................................Grasshoppers and Crickets Orthoptera

9b.Prothorax smaller than meso and meta thorax, legs normally similar in thickness, if hind legs enlarged then not used for jumping..................................................................................Stick-Insects Orthoptera

10a. Fore-wings short..................................................................................................11

10b.Fore-wings as long as, or nearly as long as abdomen the 2 wings may be joined where they meet along the animals back and hence never used for flying  …………………………..Beetles Coleoptera

11a. End of abdomen with characteristic pair of forceps like cerci........Earwigs Dermaptera

11b. End of abdomen with out characteristic forceps like cerci................Beetles Coleoptera

12a. Wings narrow and without veins, but fringed with long hairs. Very small insects, about 5 mm in length .............................................................................................................................Thrips Thysanoptera

12b. Wings more fully developed, and with veins present....................................13

13a. Hind-wings noticeably smaller than fore-wings..............................................14

13b. Hind-wings similar in size to or larger than fore-wings.................................19

14a. Abdomen with two or three long 'tails'. Fore-wings with a large number of cross-veins, making a net-like pattern............................................................................................................ Mayflies Ephemeroptera

14b. Fore-wings with fewer veins, not forming a net-like pattern, usually without 'tails' ..........................................................................................................................................15

15a. Wings obviously hairy. Mouth-parts very small, except for palpi  Caddisflies Trichoptera

15b. Wings not obviously hairy, though tiny hairs can be seen under the microscope 16

16a. Mouth-parts well developed and adapted for biting and chewing...............17

16b. Mouth-parts tube-like, adapted for piercing and sucking  Aphids; Cicadas etc Homoptera

17a. Very small insects, soft-bodied, mostly less than 6 mm. in length. tarsi with only two or three segments …………………………………......................................................................................18

17b. Often much bigger, wasp-like or bee-like insects; or if very small, then hard-bodied, with abdomen narrowed at its base into a 'waist'. tarsi with four or five segments Bees, Wasps, Ants and Sawflies Hymenoptera

18a. Antennae with 9 segments only.................................................................. rareZoraptera

18b. Antennae with 12 to 50 segments........................................Bark or Book Lice Psocoptera

19a. Tarsi with three or four segments only ..............................................................20

19b. Tarsi with five segments....................................................................................... 23

20a. Tarsi with 3 segments only; first segment of anterior (front) legs greatly swollen Webspinners Embioptera

20b. Tarsi with 3 or 4 segments, if 3 then first segment of anterior legs not swollen 21

21a.Wings with few cross-veins, fore-wings differently shaped to hind-wings which are greatly expanded posteriorly......................................................................................................Stoneflies Plecoptera

21b.Wings with numerous cross veins, fore- and hind-wings usually very similar in shape, though hind-wings occasionally enlarged posteriorly................................................................................22

22a. Small insects, generally much less than 25 mm in length with long antennae, and with wings folded flat over body…........................................................................................................….Termites Isoptera

22b. Generally longer than 25 mm, with very short antennae. Wings held away from body when at rest

.................................................................................................................... Dragonflies Odonata

23a. Mouth-parts prolonged into a beak. ...........................................Scorpionflies Mecoptera

23b. Mouth-parts short...................................................................................................24

24a. Most of the veins in forewings divide or fork just before they reach the wing edge, hind-wings broader than fore-wings at least at base ……………………………...........Alderflies, Snakeflies Neuroptera

24b. Few or no veins in the forewings fork immediately before the wing edge, hind-wings similar to fore-wings..............................................................................................................Lacewings Neuroptera

25a. Hind-wings absent or reduced knob-like organs (called halteres)...................26

25b. Forewings absent or reduced to knob-like organ.................................Stylops Strepsiptera

26a. Hind-wings reduced or modified to knob-like organs (called halteres) Mouth-parts of various forms          ………………………………………………………………………………..true Flies Diptera

26b. Hind-wings entirely absent; no halteres. .................................Some Mayflies Ephemeroptera

27a. Some segments with jointed legs, which can be used for movement..............28

27b. No jointed legs; or if these are present and visible, then they are enclosed in membrane, and cannot move  …………..Larvae and Pupae of Endopterygota  (special keys needed to get these)

28a. Animals found living as parasites on warm-blooded animals, or found closely associated with them

………………………………………………………………………………………….....29

28b. Animals not found living as parasites on warm-blooded animals: either free living, or parasitic on other insects, snails etc...............................................................................................................34

29a. Body flattened from side to side, hard and bristly, with strong legs, jumping insects, found on birds and mammals..................................................................................................................Fleas Siphonaptera

29b. Insects not as above, body either rounded or flattened from above ...............30

30a. Mouth-parts adapted for biting and or chewing.................................................31

30b. Mouth-parts adapted for piercing and or sucking..............................................32

31a. Posterior end of the body with cerci. Found on bats and small rodents in tropical environments only ............................................................................................................. Parasitic earwigs Dermaptera

31b. Posterior end of body without cerci. On birds or mammals all over the world Chewing lice Mallophaga

32a. Flattened, rather spider-like insects, with head fitting into a notch on thorax, and with antennae not visible. Claws hooked............................................................................Louseflies and Batflies Diptera

32b. Not spider-like. Antennae clearly visible .............................................................33

33a. Snout (proboscis) short, unjointed. Body long and narrow. Tarsi of legs with one large, hooked claw. Permanent parasites of birds and mammals..........................................Sucking lice Anoplura

33b. Snout (proboscis) longer, jointed. Body more oval. tarsi with two small claws, not hook-like. Only temporary parasites....................................................................................................Wingless bugs Hemiptera

34a. Terrestrial: living on dry land, or on animals other than mammals and birds 35

34b. Aquatic: mostly nymphal forms of terrestrial insects..........................................60

35a. Mouth-parts not visible. Abdomen with appendages on some of the abdominal segments, or with a forked 'spring' near tip...................................................................................................................36

35b. Mouth-parts clearly visible.......................................................................................39

36a. Abdomen with six segments or fewer, usually with a forked appendage ('spring') near tip. No long bristles at tip of abdomen................................................................................................ Springtails Collembola

36b. Abdomen with nine or more segments. No spring, but several segments have simple appendages ................................................................................................................................................37

37a. Cerci present, sometimes appearing as clasping forceps......................................38

37b. No cerci........................................................................................................................Protura

38a. A central 'cerciform tergum' projects between the cerci giving the appearance of 3 'tails' .........................................................................................................3-Pronged Bristletails Thysanura

38b. No central 'cerciform tergum', hence having the appearance of 2 'tails'-2 Pronged Bristletails Diplura

39a. Mouthparts mostly adapted for piercing or sucking............................................40

39b. Mouth-parts not as above, adapted for biting and or chewing...........................44

40a. Body covered with scales and or dense hairs............................Wingless Moths Lepidoptera

40b. Body bare, or with few scattered hairs ...................................................................41

41a. Almost all of thorax that is visible above is composed of the middle segment, the mesothorax: prothorax and metathorax both small and hidden............................................... Wingless True flies Diptera

41b. Mesothorax and metathorax about equally developed. Prothorax also is usually visible from above ................................................................................................................................................42

42a. Snout (proboscis) small, cone-shaped. Body long and narrow. Claws usually absent  Thrips Thysanoptera

42b. Snout (proboscis) longer, jointed. Body more or less oval. Claws present.........43

43a. Proboscis arising from front part of head. Abdomen without cornicles near tip Wingless Bugs Hemiptera

43b. Proboscis arising from hind part of head. Abdomen often with two cornicles at or near its tip ...................................................................................................................................Aphids Homoptera

44a. Abdomen with false or pro-legs, which are fleshy, and different from the jointed legs of the thorax. Caterpillar-like......................................................................................................................45

44b. Abdomen without any kind of legs, only thorax has legs.....................................47

45a. Five pairs of prolegs, or fewer, with minute hooks (crochets); none on the1st or 2nd abdominal segments …………............................................................................................................Caterpillars Lepidoptera

45b. Six to ten pairs of prolegs, always with one pair on the 2nd abdominal segment. No crochets present ..................................................................................................................................................46

46a. Head with a single ocellus (small eye) on each side.............. Larvae of Sawflies Hymenoptera

46b. Head with several ocelli on each side............................. Larvae of Scorpionflies  Mecoptera

47a. Antennae short and indistinct. Larvae.......................................................................48

47b. Antennae long and distinct. Adult insects.................................................................50

48a. Body Caterpillar-like.....................................................................................................49

48b. Body not caterpillar-like...................................................... Larvae of some insects Neuroptera or Coleoptera

49a. Head with six ocelli on each side of head…….. ..................................Caterpillars Lepidoptera

49b. Head with more than six ocelli on each side.................................Larvae of some Mecoptera

50a. Abdomen with a pair of movable forceps like cerci at tip.......................Earwigs Dermaptera

50b. Abdomen without such forceps...................................................................................51

51a. Abdomen strongly constricted at base into a 'waist'. Sometimes antennae are bent into an elbow ....................................................................................................Ants and wingless Wasps Hymenoptera

51b. Abdomen not constricted into a waist.........................................................................52

52a. Head prolonged underneath body into a long beak, which bears mandibles at its tip.Scorpionflies Mecoptera

52b. Head not prolonged into a beak...................................................................................53

53a. Tiny soft insects ..............................................................................................................54

53b. Fairly small, to very big, usually hard-bodied insect................................................55

54a. Cerci absent.............................................................................. Booklice and Barklice Psocoptera

54b. Cerci present....................................................................................................................Zoraptera

55a. Hind-legs enlarged for jumping........................................ Grasshoppers/Crickets Orthoptera

55b. Hind-legs not enlarged for jumping .............................................................................56

56a. Tarsi of legs with four segments. Pale, soft-bodied insects living in wood or soil. Termites Isoptera

56b. Tarsi of legs with five segments. More highly colored insects..................................57

57a.Body dorsoventrally flattened.................................................................Cockroaches Orthoptera

57b. Body not dorsoventrally flattened rounded or squarish in section..........................58

Cerci long, containing 8 segments, eyes reduced or absent.............................................. Orthoptera  

Cerci not as above, eyes well developed................................................................................59

59a. Fore-legs modified for grasping and holding, predatory........................................... Orthoptera

59b. Fore-legs not so modified...........................................................................Stick Insects Orthoptera

60a. Mouth-parts adapted for piercing and sucking. ..Nymphs of Water-bugs Hemiptera and some Neuroptera

60b. Mouth-parts adapted for licking and chewing.............................................................61

61a. Body enclosed in a case made of pebbles, sand and debris....Larvae of Caddisflies Trichoptera

61b. Body not enclosed in such a case....................................................................................62

62a. Abdomen with external gills...........................................................................................63

62b. Abdomen without external gills.....................................................................................64

63a. With two or three long processes at tip of abdomen, traces of wing-cases may be visible in later instars ................................................................................................................. nymphs of Mayflies Ephemeroptera

63b. Only one process at tip of abdomen, and no wing-cases visible.............Alderflies Neuroptera

64a. Head with a 'mask', bearing the jaws which is capable of being extended far forward of the insect's body ............................................................................................................Nymphs of Dragonflies Odonata

64b. Head without such a mask...............................................................................................65

65a. With long antennae; and long filaments at tip of abdomen.....Larvae of Stoneflies Plecoptera

65b. Without such filaments......................................................................Larvae of Beetles Coleoptera