A Ladder of Endemicity: A pioneering study of anuran communities along an elevational gradient in the Eastern Andean Cloud Forests, Ecuador

Per unit of area, Ecuador is home to the most herpetofauna of any region on Earth, yet many ecosystems are under researched. Positioned between the Eastern Andes and the Amazon rainforest, the Río Pastaza Basin of Ecuador has been the recent focus of anuran biodiversity surveys and is home to many endemic species. This study aimed to determine how the anuran community composition of a vertical transect in the Llanganates National Park varied between elevations. A 7-day expedition was conducted along a new trail up Abitagua Range spanning 1,050 m in elevation. Each night, visual encounter surveys were employed to assess the species richness, biodiversity, and similarity of each site sampled. The 6 sites were grouped into 3 categories by habitat type and elevation: Disturbed Forest (1,450-1,500 m), Low Primary Forest (1,450-1,675 m), and High Primary Forest (2,150-2,500 m). Each site housed very different community compositions, and 7 potentially new species were discovered above 1,600 m elevation. The Primary High group had the highest diversity, and 6 of the potentially new species were discovered in that elevational range. Future investigation should focus on high elevation habitats in the Llanganates as a source of undiscovered herpetofauna biodiversity. Resumen: Para unidad de área, Ecuador tiene la cantidad más alta de herpetofauna en el mundo, pero muchos ecosistemas no han sido investigados. Entre los Cordillera Oriental de los Andes y la Amazonía Ecuatoriana, la cuenca del Rió Pastaza ha sido el enfoque de investigaciones recientes de la biodiversidad de ranas, y la región es el hogar de muchas especies endémicas. Este estudio intentó analizar cómo la composición de las comunidades de ranas se diferencia entre alturas diferentes con un transecto vertical en el Parque Nacional Llanganates. Una expedición de 7 días fue cumplida a lo largo de un sendero nuevo de 1,050 metros de altura en la Cordillera Abitagua. Cada noche, muestreos de encuentra visual fueron hechos para evaluar la biodiversidad y la riqueza de especies en cada sitio valorado. Los 6 sitios fueron divididos en 3 grupos según su tipo de hábitat y altura: Bosque Afectado (1,450-1,500 m), Bajo Bosque Primario (1,450-1,675 m), y Alto Bosque Primario (2,150-2,500 m). Cada sitio tuvo una comunidad muy diferente, y 7 especies posiblemente nuevas se descubrió arriba de 1,600 m de altura. El Alto Bosque Primario tuvo la biodiversidad más alta de los tres grupos, y 6 de las especies posiblemente nuevas se descubrió en este rango de altura. Estudios en el futuro se deben enfocar en las regiones de elevación alta en los Llanganates como una fuente de biodiversidad de herpetofauna no descubierto. Acknowledgements: I would like to sincerely thank my teachers, Xavier Silva, Diana Serrano, and Ana María Ortega, for their guidance and continued support during this project. Thank you to Alex Bentley for being my research advisor, providing advice, and for answering my many questions. A huge thank you to Zane Libke for helping me conceptualize and direct my project focus, sharing your knowledge of herpetofauna and your amazing photos, and for inspiring my love of frogs. To Henry Sánchez, Mamita Gloria, Vicente Sánchez, and the team at Sumak Kawsay In Situ, I am deeply grateful for your support and care of me throughout each phase of my project. To Eli Bieri, Sara Dykman, Kira Miller, Jordi Salazar, and the expedition team, I am honored to have shared that incredible and challenging experience with each of you. Thank you for encouraging me onwards on the toughest days. I would also like extend my gratitude to Lou Jost, Julio Carrión and Pearson McGovern for your insight into data analysis. Finally, thank you to my family for encouraging my passion for science and for making this research opportunity possible.