Abstract
The embryonic scales of two Australian agamine lizards (Hypsilurus spinipes and Physignatus lesueuerii) derive from the undulation of the epidermis to form dome-shaped scale anlage that later become asymmetric and produce keratinized layers. Glycogen is contained in basal and suprabasal cells of the forming outer scale surface that are destined to differentiate into β-keratin cells. The outer peridermis is very flat, but the second epidermal layer, provisionally identified as an inner peridermis, is composed of large cells that accumulate vesicular bodies and a network of coarse filaments. The sequence of epidermal layers produced beneath the inner peridermis in these agamine lizards corresponds to that of previously studied lizards, but the first subperidermal layer has characteristics of both clear (keratohyalin-like granules) and oberhautchen (dark β-keratin packets) cells. This layer is here identified as an oberhautchen since it fuses with the underlying β-keratinizing cells forming large spinulae as the entire tissue becomes syncytial so that the units appear to increase in size. These spinulae very likely represent sections of honeycomb-shaped micro-ornamentations. A mesos layer appears underneath the β-layer before hatching. J. Morphol. 240:251-266, 1999. © 1999 Wiley-Liss, Inc.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.