Based on prior knowledge, we can determine the appropriate ranges of values for the BMI age group classification. Here, we will assume that an individual is classified as a senior if their BMI is greater than or equal to 25, and as a non-senior (adult) if their BMI is less than 25.

To complete the task, we need to identify five typical BMI values for each target class: 'Adult' and 'Senior'.

Here is the dictionary with the requested information:

```json
{
  "Adult": [22.5, 23.8, 24.1, 21.9, 23.7],
  "Senior": [25.4, 27.2, 26.1, 26.8, 25.9]
}
```

Please note that the BMI values provided are hypothetical examples and should not be considered as actual statistical data.