Architecture of Envenomation: A Histological Study of the Scorpion Telson and Its Venom Glands

Scorpions, members of the class Arachnida, possess a specialized venom apparatus used in both predation and defense. This system is located in the telson, the terminal segment of the metasoma, which houses the venom glands and enables controlled venom delivery. The present study examines the histological organization of the telson in three representative species namely, Hottentota tamulus (Fabricius 1798), Scorpiops deccanensis (Tikader & Bastawade, 1983), Deccanometrus xanthopus (Pocock 1987 revised to Deccanometrus by Zoological Survey of India checklist 2021) belonging to families Buthidae (Koch 1837), Scorpiopidae(Kraepelin 1905) and Scorpionidae (Pierre 1802) to assess the structural patterns across taxa. Three specimens of each species were utilized for the experimental study. Telson tissues were processed using standard histological methods and stained with Hematoxylin and Eosin (H & E). Microscopic observations revealed a consistent basic structural arrangement across species, including a dense outer cuticle, a thin but active epidermal layer, well developed paired venom glands, associated ducts, surrounding muscle fibers and scattered neural elements. The venom glands occupy most of the vesicle and are composed of secretory epithelial cells arranged around a central lumen, closely associated with ducts leading to the aculeus, surrounded by strong musculature. The close and intricate association between the glandular tissue and musculature suggests an efficient mechanism for venom expulsion. The presence of the scattered neural elements suggest a supportive regulatory control over the envenomation system. Overall, the study indicates conserved microanatomical organization reflecting a clear relationship between structure and function, with typical variations existing in the glandular structure and muscular development. These findings provide a strong basis for understanding the process of venom delivery in scorpions and broader insights into the effectiveness of the telson as an envenomation organ across the studied species.