Subject: Suspected phoresy on squash bug actually battle casualty?
Location: Pelham, Ontario, Canada
April 28, 2017 7:00 am
Hi! Love the site – long time viewer and occasional contributor!
I was at a golf club and spotted a true bug, which I think may be a squash bug. Sorry for the blurry photo — can you help with ID? I supplied a second shot of the head, which is what made me think it was a squash bug – it is similar to BugGuide photos.
After looking at my photo on my camera’s screen, I noticed something attached to the bug’s antenna. I was excited at first because I like pseudoscorpions and I thought I might be seeing pseudoscorpion phoresy, like in some other excellent photos on your website. I flipped my lens around to attempt some reverse macro shots and although those were blurry too I did manage to get a few somewhat in focus.. and it looks like what I thought was phoresy was actually the results from a battle between the squash bug and some ants. There’s an ant — it looks like it could be quite dead, although it might just be quite tenacious — firmly affixed to the antenna of the squash bug. In one of the photos you can clearly see the ant’s sharp mandible sliced into the antenna.
Anyway, I thought you might like the story and the photos. Love the site!
Thanks so much for the compliment. We agree, based on comparison with this BugGuide image, that you found a Squash Bug in the genus Anasa. We do not believe the Ant on the antenna can be classified as phoresy which is defined on Amateur Entomologists Society as “Phoresy is the act of ‘hitching a lift’ on another organism. As invertebrates are small and not all have wings many travel comparatively long distances by using other, more mobile, organisms. … Another good example is that of pseudoscorpions are small arachnids that resemble scorpions without the long tail and sting. When a flying insect lands nearby the pseudoscorpions grab hold of the larger insect using their pincers. When the insect flies to a new location they carry the pseudoscorpion with them.” Since Ants are social creatures that depend upon being able to find their way back to the colony, phoresy would have no advantage to the Ant. We agree with your “battle” supposition, so we will tag this as Food Chain. We noticed the spines on the thorax of the Ant, and we wonder if it might be an Acrobat Ant in the genus Crematogaster which is pictured on BugGuide. According to BugGuide: “workers and males 2.5-3.5mm.” Bugs in the News provides some very interesting information on Acrobat Ants preying upon plant-feeding insects to help protect Homopteran insects they are farming: “Their food, throughout the year, consists primarily of the honeydew secretions of homopteran insects. In fact, they are well-known for farming colonies of such insects as a means of providing their members with a ready supply of the latter’s sweet liquid exudations.
As I mention in an earlier article on acrobat ants found in Temple, Texas, most gardeners are dismayed to find evidence of homopteran incursions onto their garden plants because, once established, the damage done by these organisms can be extensive and difficult to control. Since acrobat ants work hard to disperse scale, aphids, and mealybugs, one might think the first thing a good gardener should do is to control these ants. Again, first impressions are not always best, as the following demonstrates: ‘The cultivation of Homoptera by ants is usually considered detrimental to plants, but any damage may be offset by the ants’ predation on defoliators. Another factor that may contribute to the stability of the ant-Homoptera-plant relationship is the ability of some homopterans to withdreaw large quantities of sap without seriously injuring trees, thereby allowing them to feed on the same plant year after year (Bradley and Hinks 1968). A portion of the sap sustains the aphids, but most is passed on as honeydew to the ants. In return, the ants protect the aphids and the trees from their enemies.’ (Hansen and Klotz 2005).”