Wednesday, September 28, 2016

Hibiscus Plant Bug

Colorful bugs in a seed head - REK
At the Master Naturalist Bioblitz last Saturday, one of my favorites was spotted by Linda Ellis who was leading the plant team.  There were a lot of seed heads on the the Halberd-leaf Rosemallow, Hibiscus militaris, aka H. laevis,  along the bridge over the water garden.  While she was collecting seed she noticed these tiny beetles.

Multiple instars- REK
The bugs that I shook out of the seed heads were too small for my macro and traveled too fast for the microscope so they went into my tolerant loving wife's refrigerator.  These are Scentless Plant Bug larvae, formally called Niesthrea louisianica.  They are very colorful and noted to have a wide range of colors.

Chilling out under the microscope
Like their stink bug cousins they have a proboscis that drills into the plant and sucks out its juices.  We are plagued by Box Elder bugs with similar habits but these don't come inside to overwinter in our houses.  Instead they stay in the duff, mate in the spring and raise several generations over the summer. 

There are lots of mallows in nature including cotton and okra.  I wear cotton but have a pathological aversion to okra to the point that I delighted in brush hogging the plants that remained in our garden at the end of the season.

H. militaris larva on a toothpick
On the other hand, there is the invasive Velvetleaf (Abutilon theophrasti) which was introduced to the US from China in the 1750's to make rope but failed to be popular.  It can be eaten with some effort but so can many weeds.  It is a pest in agricultural fields and our little H. militaris has developed an appetite for it.  Introduction into fields has reduced the population of these weeds.

I didn't find any adults among the two dozen I collected but I am sure they are out there.  They didn't seem to have any noticeable impact on our mallow which were going to seed quite successfully.  This is just one more example of a food web, for good or bad, under our radar.

Details at Bugoftheweek.com