Figure 1

Overview of Hislopia malayensis morphology. (a) View from the basal side of colony detached from the substrate showing the arrangement of the flat encrusting zooids and the communication sites to neighbouring zooids (asterisks) (on-light, stereo-microscope). (b) Fragment of a colony viewed from the frontal side to show the arrangement of the zooids and the polypides within each zooid. (bright-field transmitted light, stereo-microscope). (c) Older bud already showing the typical oval shape of the adult zooids with a new bud arising as a slender process on its distal side (dark-field transmitted light, stereo-microscope). (d) Detail of a single zooid showing most of the polypides morphological features (differential interference constrast). Abbreviations: a - atrium enclosed by the tentacle sheath, cae - caecum, cw - cystid wall, es - esophagus, int - intestine, lb - lophophoral base, nz - neighbouring zooid, o - orifice, ob - old bud, p - polypide, pa - polypide anlage, ph - pharynx, pv - proventriculus, t - tentacles, z - zooid. Scale bar in (a) and (b) = 400 μm, (c) and (d) = 200 μm.