A morpho-histological analysis of the exoskeleton of Clathrozoella medeae (Cnidaria, Hydrozoa) reveals insights into the taxonomy of Clathrozoellidae and Hydroidolina

Author(s)

Mendoza-Becerril, Maria A. ; Marques, Antonio C.

• Document type: Journal article
• Source: PeerJ; v. 13, p. 13-pg., 2025-01-09.

Abstract

The taxonomic complexity of the families Clathrozoidae and Clathrozoellidae, rooted in early 20th-century hydroid descriptions, highlights the need for comprehensive and detailed morphological analyses. This study aimed to elucidate the histology of the polypoid stage of Clathrozoella medeae Pena Cantero, Vervoort & Watson, 2003, with a particular emphasis on its exoskeletal structure. Specimens from the National Museum of Natural History were examined histologically using different staining techniques. The results revealed a three-layered mesoglea, diverse gland cells, and an exoskeleton comprising chitin and structural proteins, with notable differences from other anthoathecate hydroids. These results have significant implications for the taxonomy and evolutionary relationships of Clathrozoellidae and Hydroidolina, as they highlight the importance of detailed histological data in understanding the unique exoskeletal architecture of C. medeae, termed "exoskeleton tube", which distinguishes it from other hydroids, and provide critical insights into the homology and phylogenetic position of Clathrozoellidae. (AU)

• FAPESP's process: 11/50242-5 - Dimensions of marine life: patterns and process of diversifications in planktonic and benthic cnidarians
• Grantee: Antonio Carlos Marques
• Support Opportunities: BIOTA-FAPESP Program - Thematic Grants
• FAPESP's process: 10/06927-0 - Biodiversity and areas of endemism of benthic hydroids (Cnidaria, Hydrozoa) from southern South America and Antarctica
• Grantee: Thaís Pires Miranda
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 23/17191-5 - Advancing the utilization of cnidomes for evolutionary and diversity studies in Medusozoa
• Grantee: Antonio Carlos Marques
• Support Opportunities: Scholarships abroad - Research