Fig. 9

A Monophyllum galalaensis n. sp. (Holotype specimen, Rah 9). A1 Lateral external view of the corallite, positions of thin-sections indicated in A1. A2 A calice view of the paratype specimen (RAh 41), with eroded rim, shows an elongated counter septum that form a columella (arrow). A3–A5 Successive transverse thin-sections of the neanic stage, showing the pseudo-radial to pinnate arrangement of major septa, a long thin ended cardinal septum, and a longer counter septum with a swollen end in a dense stereocolumn. A6–7 Two successive mature sections, showing a short cardinal septum. A8^1,2 Transverse thin-section in the late mature stage below the calice, showing radially arranged major septa that retreat a little leaving a narrow free axial area occupied by the elongated part of the counter septum. Note, A8² is a redrawing of section A8¹. Paratype specimen (RAh 13). External alar view of the corallite, positions of thin-sections are indicated in white lines. B2 Nepionic stage. B3 Early neanic stage. B4–5 Two partly compressed successive mature sections (ephebic stage), show a distinctly long counter septum. B6 Last mature section—more or less in the calice—showing a detached columella that is separated from the long counter septum. Black dots indicate the positions of cardinal septum (below), counter septum (above) and the two alar septa