|Vespula pensylvanica, Western Yellow Jacket (social), Ancistrocerus tuberculocephalus (solitary), Mischocyttarus navajo (social), Polistes comanchus (social)|
|Climaciella brunnea (Wasp Mantidfly), and Polistes comanchus|
Social wasps are probably among the most aggressive defenders of their hive area, so they have many very close mimics. Previously I showed an examples for Muellerian mimicry. Here are some of many examples of Batesian imitators: The Wasp Mantisfly (Neuroptera) is shown with one of its models Polistes comanchus. But other individual in the same mantispid species strikingly imitates solid brown and more strongly banded Polistes species.
Also note the locations (on the individual images): all occur together at higher elevations..
|Longhorned Beetle Strophiona tigrina|
|Several Acmaeodera species in the family of the Metallic Wood-boring Beetles|
|Longhorn Beetle Tragidion decipiens, Tarantula Hawk, Hemipepsis ustulata, and Mydas Fly Mydas xanthopterus, Photo Bob Barber|
|Phidippus apacheanus and Dasymutilla sp.|
Here is a little Coreid (Leaf-footed Bug) nymph in the genus Narnia and her mom. The little ones were all over the juicy fruit of a Barrel Cactus and its extra-floral nectaries while the adult was hiding among the thorns, very much out of reach. Where the little ones just naively taking a risk or were they protected? The barrel cactus fruit and nectaries are often visited (and owned) by the very defensive local fireants Solenopsis xyloni. The bug nymphs resemble the ants in size, color and preferred location. Not so much in shape. But the resemblance really does not have to confuse the human eye as long as it repels a predator
To dispel the idea that only the very painful stingers among hymenoptera can be mimicry models: Here is a peaceful, flightless, dusk-active darkling beetle, Eleodes armatus on the right. A stink beetle, like all of his genus and many in his family). There are 2 huge glands in his abdomen that douse him and the prospective predator's nose with very obnoxious chemicals. To get good coverage, he lift his hind end where the glands open, high into the air and lets gravity do some of the work. The same-sized Cactus Longhorn Beetles here Moneilema appressum is also dark, flightless, and has to move between cacti across the light desert sand at dusk. So it does a stop-and-go walk, just like Eleodes and even lifts its behind when disturbed. The big dark Calosoma species (Ground Beetle, Carabidae) also joins in the behavioral mimicry, but those guys can release a nice stink by themselves ....
|Pipvine Swallowtail, Battus philenor|
|Red-spotted Purple, Limentis arthemis|
So where the model is not around in sufficient numbers, the similarity provided no advantage and did not evolve.
|Lycus simulans and Elytroleptus ignitus|
Were there enough mimics to endanger the whole system? Did naive predators get lucky too often so they did not learn to avoid the insects?
Anyway, there is something very interesting going on in SE Arizona: Several species of the Longhorn Beetle genus Elytroleptus usually associate with the toxic Lycids around oak trees (extra floral nectaries) and on flowers. In those mixed groups, many Lycids looked like they had been chewed on. Holes in the elytra, leaking heamolymph ... Normally we think of all Longhorn Beetles as strictly vegetarian. But it turned out that Elytroleptus were chewing on Lycus, and chemical analyses revealed that the Longhorns were actually incorporating (sequestering) the toxins of the Lycids. A Batesian mimic becoming Muellerian at the cost of its model!