Histological study of the sacroiliac articulation in Scinaxini (Anura: Hylidae: Hylinae)

• Grant number: 25/24198-1
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: March 20, 2026
• End date: September 19, 2026
• Field of knowledge: Biological Sciences - Zoology - Morphology of Recent Groups
• Principal Investigator: Célio Fernando Baptista Haddad
• Grantee: Mariana Vaini Marques
• Supervisor: Julian Faivovich
• Host Institution: Centro de Aquicultura (CAUNESP). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Institution abroad: Museo Argentino De Ciencias Naturales Bernardino Rivadavia, Argentina
• Associated to the scholarship: 24/07182-1 - Diversity and evolution of the sacroiliac joint in Scinaxini., BP.MS

Abstract

The sacroiliac articulation in anurans is crucial for movement, with variations in shape linked to different joint motions and behaviors. Our focus is on the tribe Scinaxini, specifically the genus Julianus, which shows a unique sacroiliac morphology characterized by medially expanded sacral sesamoids and reduced sacral diapophyses. These characteristics suggest a new type of sacroiliac joint, possibly with two sub-joints. Using histological studies, this research aims to detail the structure of the sacroiliac articulation in Scinaxini, examining ligament attachments and the development zones of the articulation, to determine if Julianus has a compound sacroiliac articulation. By combining histology and morphology, we attempt to enhance our understanding of pelvic evolution in neotropical treefrogs and address important gaps in anuran movement diversity.