Tuesday, June 27, 2017

June Flies

My interest in flies (order Diptera) has been increasing the past few years.  Here are a few I've come across recently.  All pictures were taken with my iPhone in and around Minneapolis in June.

Toxomerus marginatus
One of the many bee mimics in the flower fly family, Syrphidae.  The larva eat aphids, which are doing serious damage to some of the wildflowers in our backyard this year.  It's very possible the larva in the photo below is of T. marginatus.

Ptecticus sp.
 This fly is in the soldier fly family, Stratiomyidae.  According to Bug Guide there are five North American species.  P. trivittatus is the only species found in MN pictured at Bug Guide.  They are regular summer inhabitants around our compost bin.

Ctenophora nubecula
A species of crane fly, family Tipulidae.  Crane flies represent a different taxonomic branch of the Diptera.  Despite resembling a super-sized mosquito, they are harmless.

Wednesday, June 7, 2017

Painted Turtle with Snapping Turtle

A number of years ago I was witness to an odd animal sight; two small painted turtles, Chrysemys picta basking on a floating snapping turtle, Chelydra serpentina.  Nobody really believed me.

But this week I saw a similar sight (and with witnesses).  This time it was one painted turtle with one snapping turtle.  The snapper was mostly submerged with just its snout out of the water.  The painted turtle was floating just  above it.  Occasionally the painted turtle took a good nibble at the snapper.  We all expected retaliation from the snapping turtle, but none came.  The snapper barely registered the bite.

So what was happening?  We entertained a few ideas before coming up with a plausible explanation.  We speculated that the painted turtle was eating leeches off the snapper.  Later I looked for some information on this behavior.  I found a few references to this behavior, including a scholarly article from the journal Canadian Field Naturalist.  I wonder if this is a rare interaction, or maybe only occurs in certain types of water bodies.  Or maybe it's a common, but rarely observed because snapping turtles spend so much of their lives at the bottom of lakes and pond.

Saturday, June 3, 2017

Two Late May Moths

Nessus Sphinx Moth - Amphion floridensis
In the Sphinx Moth family, Sphingidae.  It's been in our backyard for a few days; its wings are pretty beat up so its usually in the grass struggling to fly.  We've been putting it on Virginia Waterleaf that grows abundantly in our yard and is in full bloom right now.  But the next time I see it, I'm going to put it on a grapevine, which is what the larva feed on.

Polyphemus Moth - Antheraea polyphemus

Giant Silkworm and Royal Moth family, Saturniidae.  Thank you Debbie for showing me this moth and not thinking it was a big leaf.

Both moths happen to feature a character from Greek mythology in their names.  Nessus was a centaur whose trickery led to the death of Heracles.  Polyphemus was a cyclops from the Odyssey.  There's a tradition of naming moths the larger North American Silkworm moths after figures from Greek mythology.  A few sphinx moths have myth inspired name, but not consistently so.  If anything, many N. American sphinx moths are named after their caterpillar's host plant.