Description of the tadpole and natural history notes of Incilius spiculatus (Mendelson, 1997), an Endangered toad endemic to the Sierra Madre de Oaxaca, Mexico

Amphibian populations are declining rapidly around the world. However, new amphibian species keep being discovered, reflecting the still expanding state of our knowledge of this group. Similarly, there is a lack of information regarding life cycles, particularly among those species that have indirect development with a free-living larval stage. Many amphibian larvae are still unknown or undescribed, thus impeding a proper understanding of the biology and habitat use of many species. In this paper, we describe the tadpole of the Endangered bufonid anuran Incilius spiculatus, a member of a clade known as forest toads. Also described are the amplexus behavior of this species observed in nature, and aspects of the natural history of the adult stage. A tadpole identification key is provided for the forest toad clade of Mexico and Central America. This information contributes to the understanding of the life history of I. spiculatus, in addition to its diet and distributional patterns. This article highlights the importance of knowing the complete life cycle of a species in order to establish effective conservation plans, particularly for those species with limited distributions in highly managed ecosystems.