3/13/2022: The amazing behind of Scolopendra heros arizonensis

My lovely lady Scolopendra heros arizonensis never ceases to intrigue. She’s grown quite rotund from the steady stream of feeder roaches, and considering she’s an honorary Texan having been found in Texas Canyon (Arizona), I’ve decided to name her Miss Texas.

Miss Texas was quite performative last feeding, and exhibited a behavior I hadn’t fully recognized before. While holding her prey and upon feeling threatened, her back end reared up and assumed a position uncannily similar to her front end, right down to imitation gnathopods.

This poses the question… why did this impressive combination of physical and behavioral mimicry come about? Why does arizonensis need a decoy back end? It could even be argued that the markings are an example of a superstimulus, where an exaggerated signal is better received by its target than the signal that original triggered the response. In this case, the additional segments of black near the tail end would trick the predator/antagonist into attacking it over the actual head, with its one or two black segments.

The bug circle has been discussing possible explanations, ranging from it being an anti-owl, anti-coatimundi, and anti-snake mechanism. Considering the ranges for large, black front-and-back Scolopendra taxa in the United States southwest convincingly matches that of the Mexican spotted owl (including disjunctive populations!), this relationship is my personal preference. It ticks the boxes for a predator that would encounter Scolopendra when they’re active at night, yet would also be relying on decent eyesight from afar at that time. Far more information on the predator-prey relationships of these Scolopendra in the wild is absolutely needed, though. For now, the unsolved mystery will irritate the life out of me.

-Kyle