Description:
<jats:p>In the Lower Danian bryozoan limestone mounds exposed in the coastal cliff of Karlby (Jylland), fragments of cyclostome and cheilostome bryozoan colonies constitute more than 90 wt% of preserved benthic fauna in the >½ mm fractions. Of the cheilostome bryozoans, encrusting colonies normally make up between 5 and 30 wt%. The encrusting fauna is found on skeletal remains of other benthic invertebrates, predominantly stems of erect, bushy bryozoans. The proportion of encrusted stems in the fraction 1.19--1.41 mm is between five and ten times larger than in the fraction 0.500-0.595 mm. In the former fraction more than 50% of the fragments may be encrusted. Fragments of approximately identically sized stems belonging to different species are not used to equal extents as substrate. Fragments with an overall smooth, but in detail relatively coarse, surface are most often encrusted, whereas fragments are avoided that have as surface sculpture a network of ridges and hollows. Investigations of the growth site selection of six encrusting species show that specific attachment preferences according to both size and surface topography of the substrate were present, separating closely related and very similar species. This could have been anticipated from the high density and diversity of the bryozoan fauna.</jats:p>