Predaceous Diving Beetles are also called water tigers. They eat a variety of aquatic prey like other insect larvae and naiads. This species has feathery legs that help it navigate through water. It is oval shaped and small. A gold sheen covers the head and upper half of the body, while the lower black half is decorated with a bright golden yellow zigzag line that crosses the bottom of the wing coverings. Smaller flecks of golden color are also seen closer to the tip of the abdomen. A dark ‘M’-shaped line is stamped on the top of the head, and a dark line almost completely crosses the pronotum (neck area). Males have feet shaped like discs. Larvae look like armored worms with large pincers at the face.
When resting, this beetle may sit just under the water’s surface with its rear up sticking up. It is able to trap air bubbles under the elytra or wing coverings. It moves fluidly and quickly. It does have wings and can fly. This is useful in finding other freshwater habitats, even temporary ones created by rain or flooding. Look for them in small and large bodies of freshwater, especially near vegetation that grows out of the water. These areas are usually rich with small aquatic life.
Scientific Name: Acilius mediatus
Size (Adult; Length): 10mm to 16mm (0.39in to 0.62in)
Colors: black; yellow; gold
Descriptors: swimming; fins; gold zigzag; gold bottom; letter M on head; golden; water
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Antennae: Beetles have a pair of antennae on the head used as sensors.
Head: The head is home to the insect's eyes, antennae, and mandibles (jaws).
Thorax: Holds the three pairs of legs as well as vital internal organs.
Elytron: One of two wing cases on a Beetle that protects its wings (plural: elytra).
Wings: Appendages used for flying and kept under the elytra until needed.
Abdomen: Houses organs related to circulation, reproduction, and excretion.
Legs: Beetles have three pairs of legs located at the thorax, numbering six legs in all.