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Q: I found this at Smithville Lake. Can you tell me what it is?

This is a freshwater drum’s pharyngeal teeth. These molar-like teeth are tightly packed together at the back of the fish’s mouth. Because these teeth are capable of crushing shells, they were originally considered to be mollusk-eaters, but studies indicate in Missouri they mainly eat other fish, crayfish, and immature aquatic insects. They grub along the bottom, moving rocks with their snout to capture escaping prey. In places where mollusks make up more of this species’ diet, they use these shell-crushing teeth to munch on shellfish and crustaceans.

These fish are most abundant in the Missouri and Mississippi rivers and larger streams of the prairie region. They like lakes and reservoirs — like Smithville — and are often found at depths of 30 feet or more. For more information about these teeth, visit short.mdc.mo.gov/4L9.

Q: This butterfly was enjoying one of my rattlesnake master plants. Can you help identify it?

This is a male eastern tailed-blue (Cupido comyntas).

With less than a 1 1/8-inch wingspan, these small butterflies can be found statewide from April to October. 

They are the only blue butterfly with tiny tails on their hind wings. They like open sunny places and sometimes bask with their wings open at a 45-degree angle.

As caterpillars, eastern tailed-blues prefer plants in the pea family, such as sweet clover, alfalfa, and vetch. As adult butterflies, they tend to prefer flowers that are close to the ground, like this rattlesnake master plant. They’ll swarm at damp places. For more information, visit short.mdc.mo.gov/4LV.

Q: Can you explain the black belly on this squirrel?

Yes, this is a melanistic fox squirrel, according to MDC Scientist Beth Emmerich.

Unlike albinism — in which an animal is all-white — melanism is an increased amount of black or nearly black pigmentation in an organism’s skin, feathers, eyes, or hair. Melanism is caused by an excess of pigmentation, rather than a lack of it.

“That’s an interesting one,” Emmerich said, noting that the black coloration is more common on the squirrels’ backs, not their fronts.

She said sometimes a pocket of very melanistic individuals will breed, creating colonies of black squirrels.

“They are common now in the small town where I grew up in central Illinois but were not when I lived there,” Emmerich said.

For more information about this interesting phenomenon and what causes it, visit short.mdc.mo.gov/4Ly.