FIGURE 3. Rhamphostomella costata Lorenz, 1886. A, D–F, H, J–M. ZIRAS 71 in Taxonomy, ecology and zoogeography of the Recent species of Rhamphostomella Lorenz, 1886 and Mixtoscutella n. gen. (Bryozoa, Cheilostomata)

FIGURE 3. Rhamphostomella costata Lorenz, 1886. A, D–F, H, J–M. ZIRAS 71/50109 (Kodiak Island, Gulf of Alaska, Pacific Ocean). B, C, I. NHMUK 1899.5.1.273 (locality unknown). G. USNM 11148 (Point Barrow, Beaufort Sea). A. Growing margin of bilaminate erect part of colony, with one layer asynchronously encrusting opposite basal surface of another. B. Distal view of orifice of ovicellate zooid, showing lyrula and suboral avicularium. C. Suboral avicularium. D, E. Non-ovicellate zooids in young part of colony (in E, arrows indicate communication pores of future ooecia). F. Ovicellate zooids in young part of colony. G. Ovicellate zooids in older part of colony, showing ooecia overgrown by the secondary calcification and large adventitious avicularia. H. Oblique view of ovicellate zooid, showing ooecium embedded in the secondary calcification and size difference between suboral and adventitious avicularia. I. Interior of frontal shield, showing ring scar and areolae. J. Internal view of orifice, showing lyrula. K. Basal surface of one lamina of bilaminate colony. L. Close-up of frontal shield interior, showing ring scar, exterior wall microstructure of umbonuloid component and ooecial communication pore (arrow). M. Zooidal lateral walls in bilaminate colony, showing mural pore chambers. Scale bars: A, G, K, 500 μm; B, C, I, J, 100 μm; D–F, 250 μm; H, M, 200 μm; L, 50 μm.