Dichotomous Key to the Class Insecta - Interactive worksheet for identifying insects using a classification key.

Problem Overview:

The task involves using a Dichotomous Key to identify the insects shown in the images. A dichotomous key is a tool used for identifying organisms by making a series of choices between two options at each step. The goal is to follow the key's instructions and determine the correct name for each insect.

Solution Approach:

1. Understand the Dichotomous Key: The key provides a series of binary (two-choice) questions about the characteristics of the insects.
2. Analyze Each Insect Image: Carefully observe the physical features of each insect (e.g., wings, legs, body shape, appendages).
3. Follow the Key Step-by-Step: For each insect, start at the beginning of the key and make the correct choice based on its features. Continue following the path until you reach the final identification.

Step-by-Step Identification:

#### Insect 1:
- Observation: This insect has wings that extend outward from the body.
- Key Path:
- Step 1: "Insect has wings that extend outward from the body" → Go to 2.
- Step 2: "Insect has one pair of wings" → Go to 3.
- Step 3: "Legs are longer than body" → Go to 4.
- Step 4: "Insect has rounded abdomen" → Tipula abdominalis.
- Identification: Tipula abdominalis

#### Insect 2:
- Observation: This insect has wings that extend outward from the body.
- Key Path:
- Step 1: "Insect has wings that extend outward from the body" → Go to 2.
- Step 2: "Insect has one pair of wings" → Go to 3.
- Step 3: "Legs are shorter than body" → Go to 5.
- Step 5: "Wings are folded over the abdomen" → Go to 8.
- Step 8: "Antennae much shorter than body length" → Lucanus capreolus.
- Identification: Lucanus capreolus

#### Insect 3:
- Observation: This insect has wings that extend outward from the body.
- Key Path:
- Step 1: "Insect has wings that extend outward from the body" → Go to 2.
- Step 2: "Insect has one pair of wings" → Go to 3.
- Step 3: "Legs are shorter than body" → Go to 5.
- Step 5: "No wings are present" → Go to 6.
- Step 6: "Abdominal appendages are present" → Go to 7.
- Step 7: "Three abdominal appendages are present" → Lepisma saccharina.
- Identification: Lepisma saccharina

#### Insect 4:
- Observation: This insect has wings that extend outward from the body.
- Key Path:
- Step 1: "Insect has wings that extend outward from the body" → Go to 2.
- Step 2: "Insect has one pair of wings" → Go to 3.
- Step 3: "Legs are shorter than body" → Go to 5.
- Step 5: "Wings are folded over the abdomen" → Go to 8.
- Step 8: "Antennae as long as body" → Batrachyla vaga.
- Identification: Batrachyla vaga

#### Insect 5:
- Observation: This insect has wings that extend outward from the body.
- Key Path:
- Step 1: "Insect has wings that extend outward from the body" → Go to 2.
- Step 2: "Insect has two pairs of wings" → Cardulina aenea.
- Identification: Cardulina aenea

#### Insect 6:
- Observation: This insect has wings that extend outward from the body.
- Key Path:
- Step 1: "Insect has wings that extend outward from the body" → Go to 2.
- Step 2: "Insect has one pair of wings" → Go to 3.
- Step 3: "Legs are shorter than body" → Go to 5.
- Step 5: "No wings are present" → Go to 6.
- Step 6: "Abdominal appendages are absent" → Taphrina sessile.
- Identification: Taphrina sessile

#### Insect 7:
- Observation: This insect has wings that extend outward from the body.
- Key Path:
- Step 1: "Insect has wings that extend outward from the body" → Go to 2.
- Step 2: "Insect has one pair of wings" → Go to 3.
- Step 3: "Legs are shorter than body" → Go to 5.
- Step 5: "Wings are folded over the abdomen" → Go to 8.
- Step 8: "Antennae much shorter than body length" → Lucanus capreolus.
- Identification: Lucanus capreolus

#### Insect 8:
- Observation: This insect has wings that extend outward from the body.
- Key Path:
- Step 1: "Insect has wings that extend outward from the body" → Go to 2.
- Step 2: "Insect has one pair of wings" → Go to 3.
- Step 3: "Legs are shorter than body" → Go to 5.
- Step 5: "No wings are present" → Go to 6.
- Step 6: "Abdominal appendages are present" → Go to 7.
- Step 7: "Abdominal pincers are present" → Fortitula auricularia.
- Identification: Fortitula auricularia

#### Insect 9:
- Observation: This insect has wings that extend outward from the body.
- Key Path:
- Step 1: "Insect has wings that extend outward from the body" → Go to 2.
- Step 2: "Insect has one pair of wings" → Go to 3.
- Step 3: "Legs are shorter than body" → Go to 5.
- Step 5: "No wings are present" → Go to 6.
- Step 6: "Abdominal appendages are present" → Go to 7.
- Step 7: "Three abdominal appendages are present" → Lepisma saccharina.
- Identification: Lepisma saccharina

#### Insect 10:
- Observation: This insect has wings that extend outward from the body.
- Key Path:
- Step 1: "Insect has wings that extend outward from the body" → Go to 2.
- Step 2: "Insect has one pair of wings" → Go to 3.
- Step 3: "Legs are shorter than body" → Go to 5.
- Step 5: "Wings are folded over the abdomen" → Go to 8.
- Step 8: "Antennae much shorter than body length" → Lucanus capreolus.
- Identification: Lucanus capreolus

#### Insect 11:
- Observation: This insect has wings that extend outward from the body.
- Key Path:
- Step 1: "Insect has wings that extend outward from the body" → Go to 2.
- Step 2: "Insect has one pair of wings" → Go to 3.
- Step 3: "Legs are shorter than body" → Go to 5.
- Step 5: "No wings are present" → Go to 6.
- Step 6: "Abdominal appendages are present" → Go to 7.
- Step 7: "Abdominal pincers are present" → Fortitula auricularia.
- Identification: Fortitula auricularia

#### Insect 12:
- Observation: This insect has wings that extend outward from the body.
- Key Path:
- Step 1: "Insect has wings that extend outward from the body" → Go to 2.
- Step 2: "Insect has one pair of wings" → Go to 3.
- Step 3: "Legs are shorter than body" → Go to 5.
- Step 5: "No wings are present" → Go to 6.
- Step 6: "Abdominal appendages are present" → Go to 7.
- Step 7: "Three abdominal appendages are present" → Lepisma saccharina.
- Identification: Lepisma saccharina

Final Answer:

\[
\boxed{
\begin{array}{ccc}
1. \text{Tipula abdominalis} & 2. \text{Lucanus capreolus} & 3. \text{Lepisma saccharina} \\
4. \text{Batrachyla vaga} & 5. \text{Cardulina aenea} & 6. \text{Taphrina sessile} \\
7. \text{Lucanus capreolus} & 8. \text{Fortitula auricularia} & 9. \text{Lepisma saccharina} \\
10. \text{Lucanus capreolus} & 11. \text{Fortitula auricularia} & 12. \text{Lepisma saccharina}
\end{array}
}
\]