Related Experiment Video
Updated: Mar 11, 2026
Sample Preparation Method of Scanning and Transmission Electron Microscope for the Appendages of Woodboring Beetle
Published on: February 3, 2020
Thorns and dermal denticles of skates Atlantoraja cyclophora and A. castelnaui: Microscopic features and functional
Bianca de Sousa Rangel1,2, Natascha Wosnick3, Rafael Magdanelo Leandro4
1Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, travessa 14, 321, Cidade Universitária, São Paulo, SP, Brazil.
Abstract:
Some batoid species are covered with dermal denticles (or placoid scales) that occasionally develop into thorns. In sexually mature males, sharp teeth and alar thorns found on the apex of the lateral disc are used to hold the female during copulation. This study set out to analyze microscopic features of modified dermal denticles and thorns and to investigate sexual dimorphism in Atlantoraja cyclophora and A. castelnaui species. Skin samples collected from areas covered with thorns were fixed in 10% formaldehyde, processed and analyzed using scanning electron microscopy. Alar thorn morphology varied within species, while caudal thorn, rostral and caudal dermal denticle morphology varied within and between species. These structures play an important role in the protection and reproduction of the species studied and constitute important taxonomic information, given they are often the only elements preserved in archaeological sites and fossil records.
More Related Videos
10:57Scanning Electron Microscopy SEM Protocols for Problematic Plant, Oomycete, and Fungal Samples
Published on: February 3, 2017
08:09Microfocus X-ray CT microCT Imaging of Actinia equina Cnidaria, Harmothoe sp. Annelida, and Xenoturbella japonica Xenacoelomorpha
Published on: August 6, 2019
Related Concept Videos
01:11Papillary Dermis
The dermis might be considered the "core" of the integumentary system, as distinct from the epidermis and hypodermis. It contains blood and lymph vessels, nerves, and other structures, such as hair follicles and sweat glands. The dermis is made of two layers of connective tissue that comprise an interconnected mesh of elastin and collagenous fibers, produced by fibroblasts.
Papillary Layer
The papillary layer is made of loose, areolar connective tissue, which means the collagen...
01:05Accessory Structures of the Skin: Nails
The main components of a nail include the following.
Nail Plate: The nail plate is the visible portion of the nail that extends beyond the fingertips or toes. It is a hard, translucent...
01:15Reticular Dermis
Reticular Layer
Underlying the papillary layer is the much thicker reticular layer, composed of dense, irregular connective...
03:40Introduction to Seed Plants
02:40Epiphytes, Parasites, and Carnivores
01:16Accessory Structures of the Skin: Hair and Hair Follicles
Hair is a keratinous filament growing out of the epidermis. It is primarily made of dead, keratinized cells. Hair strands originate at the epidermal penetration called the hair follicle. The hair shaft is the part...