Therosette-shaped microboring trace fossil Neodendrina carnelia igen. et isp. n. – a large representative of the ichnofamily Dendrinidae – isidentified on the inner side of the giant clam Tridacna maxima fromPleistocene to Holocene coral reef deposits of the El Quseir district at theEgyptian Red Sea coast. The new dendritic bioerosion trace fossil isdiagnosed as a radial rosette comprised of a prostrate system of rooflesscanals that ramify in a strictly dichotomous fashion forming intermittentbranches of uniform width and rounded terminations. The trace appears to berare, although in the type material it occurs in a cluster of more than ahundred specimens. The location of traces on the interior surface of theshell suggests that boring occurred post-mortem to the host. Itsrecord is presently restricted to shallow marine, euphotic, tropical coralreef settings in the Western Indo-Pacific (Red Sea and Madagascar). Thebiological identity of the trace maker cannot be resolved yet, but severallines of reasoning allow speculations directed towards a complex attachmentscar, perhaps produced by a benthic foraminiferan or a macrophyte.