Which of the following is a key feature of the mature bed bug?

The key feature of a mature bed bug is that it is approximately 1/4 inch long, has a rusty-red color, and is wingless. This physical description is critical for identification, as mature bed bugs are easily recognized by their size and coloration. The absence of wings is particularly notable because it distinguishes them from many other pests that may have similar sizes but possess wings.

Understanding these characteristics is crucial for effective pest control and management, as recognizing the mature bed bug's physical traits can aid in identifying infestations and implementing appropriate treatment strategies. Knowing that they are wingless also underscores their method of movement, which relies on crawling rather than flying.

The other features mentioned in the other choices may not accurately represent mature bed bugs. For instance, while bed bugs do bite at night and can cause discomfort, they are not known to transmit diseases in Kansas, and their lack of wings is a defining feature that sets them apart from many flying insects.