In Dytiscidae, the mesothoracic legs are closer to the prothoracic legs than to the metathoracic legs. True or false?

• A. True
• B. False
• C. Not known
• D. Not applicable

Answer: (A)

Beetle leg arrangement follows thoracic segmentation: each leg pair attaches to a different thoracic segment, with front, middle, and hind legs on the prothorax, mesothorax, and metathorax respectively. In Dytiscidae, the middle legs sit between the front and hind legs on adjacent segments, and the front and middle leg bases are closer to each other than the middle and hind leg bases are. The hind legs are positioned farther back on the body and are adapted for swimming, which also emphasizes their placement behind the middle pair. Because of this overall layout on the three thoracic segments, the mesothoracic legs are closer to the prothoracic legs than to the metathoracic legs. True.