FIGURE 12 in Molecular and Morphological Diversity of Lithothamnion spp. (Hapalidiales, Rhodophyta) from Deepwater Rhodolith Beds in the Northwestern Gulf of Mexico

FIGURE 12. Lithothamnion sp. I. Specimen LAF6521. A. Thallus habit showing irregularly arranged protuberances. Scale bar 150 mm. B. Longitudinal section and partial surface view of protuberance showing putative undeveloped conceptacle (circle arrow) and new vegetative growth layer (arrow). Scale bar 450 μm. C. Longitudinal section and partial surface view of protuberance showing magnified view of new growth layer with secondary hypothallium (middle right bracket), perithallium (upper right bracket), and epithallium (left bracket) growing above older growth layer (lower right bracket). Scale bar 240 μm. D. Transverse section of protuberance showing radial construction and location of new growth layer over older part of thallus (arrow). Scale bar 400 μm. E. Magnified view of new growth layer (upper bracket) emerging out of perithallium (arrow) of older growth layer (lower bracket). Scale bar 195 μm. F. Perithallium (bracket) with abundant cell fusions in the x-axis ("black F") and z-axis (white "F"), meristematic cells ("M"), and epithallial cells with trapezoidalshaped cell lumens (arrows) and intact roofs (circle arrows). Scale bar 24 μm.