Finding love in a hopeless place: A global database of misdirected amplexus in anurans.

Amphibians are one of the most species-rich vertebrate taxa, with diverse and complex reproductive behaviors. Even though mate recognition plays a vital role in reproductive success, unusual amplexus with non-suitable mates (misdirected amplexus) have been reported to occur in the wild. Misdirected amplexus may decrease fitness, thus likely having ecological and evolutionary consequences and their frequency might increase with human-induced changes in habitat. However, it is still unclear what promotes this unusual behavior and how widespread it is at spatial and phylogenetic scales. To fill this gap, we compiled a global database of misdirected amplexus events from literature and personal observations, with detailed information on environmental, geographical, and behavioral aspects of reported events. Furthermore, we discuss its spatial, temporal, and phylogenetic patterns. We provide a data set of 378 misdirected amplexus events for 156 amplectant species distributed across 69 genera and 18 families distributed in 52 countries in all continents except Antarctica. We collected data published or collected during the last 100 years, from 1920 to 2020, with information on the hour, month, and year of the misdirected amplexus events. We recorded a total of 282 interspecific amplexus, 46 necrophiliac amplexus, and 50 amplexus with objects or non-amphibian species, with the United States and Brazil being the countries with the highest number of records. Misdirected amplexus did not occur equally in all zoogeographical realms, with most events occurring in the Neotropical and Nearctic realms. Interspecific amplexus was especially represented in the Neotropical and Mediterranean regions. Most events involved three species-rich globally distributed families (Bufonidae, Ranidae, and Hylidae) but misdirected amplexus was widespread in the phylogeny. We provide a comprehensive data set of misdirected amplexus for anurans, with our results showing that it occurs extensively in the wild and across the globe. This data set provides a baseline for understanding misdirected amplexus and their spatial, temporal, and phylogenetic patterns. Likewise, this data set offers a baseline to test the environmental, ecological, and ethological drivers behind this reproductive behavior and we encourage researchers to report detailed observations of misdirected amplexus to better understand this process and its potential costs at the individual and population levels. The data are not copyright restricted; this data paper should be cited when data are used for publication, and the authors would appreciate being notified of research projects or teaching purposes when these data are used.