Neotropical poison frogs possess alkaloid-based antipredator defenses which they sequester from a diet of arthropods such as oribatid mites and myrmicine ants. Alkaloid sequestration is still poorly understood and although several studies have examined its uptake, most experiments directly feed alkaloids to the frogs. Here, we examined the alkaloid uptake system in the poison frog species Dendrobates auratus by feeding it an alkaloid-containing prey item, the red imported fire ant Solenopsis invicta (Formicidae, Myrmicinae). Captive bred frogs were either fed live ants or fruit flies dusted with powdered ants for 4 months. Using GC–MS, we confirm that S. invicta contain previously described piperidine alkaloids known as solenopsins; however, none of these piperidine alkaloids was detected in the skin of D. auratus, suggesting the frogs are incapable of sequestering solenopsins from S. invicta. It is possible that D. auratus are unable to sequester fire ant piperidines due to their long hydrocarbon side chains, a feature that makes them structurally different than most known alkaloids in poison frogs.

新热带毒蛙拥有以生物碱为基础的抗捕食者防御，它们从节肢动物的饮食中分离出来，例如 oribatid mites 和 myrmicine ant。生物碱封存仍然知之甚少，尽管有几项研究已经检查了它的吸收，但大多数实验直接将生物碱喂给青蛙。在这里，我们通过喂食一种含有生物碱的猎物——红色进口火蚁Solenopsis invicta (Formicidae, Myrmicinae)来检查毒蛙物种Dendrobates auratus的生物碱吸收系统。圈养繁殖的青蛙被喂食活蚂蚁或撒上蚂蚁粉的果蝇 4 个月。使用 GC-MS，我们确认S. invicta含有先前描述的称为solenopsins的哌啶生物碱；然而，在D. auratus的皮肤中没有检测到这些哌啶生物碱，这表明青蛙无法从S. invicta中隔离solenopsins 。这可能是D.鲫无法封存火蚁哌啶由于其长烃侧链，这一特点使得他们比毒蛙最知名的生物碱结构不同。