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The ichnogenus Balanoglossites MA.GDEFRAU, 1932 is re-described from its type area and is interpreted as part of a complex trace fossil comprising both burrow and boring components. The type ichnospecies, B. triadicus, consists of predominantly deep U-or Y-shaped tunnel elements, whereas B. ramosus n. isp. encompasses irregularly ramified galleries. Both ichnospecies occur frequently in firmground and hardground substrates with sporadic epikarst features. In the underlying softground, they may integrate into Labyrintichnus terrerensis UCHMAN ~; ~kLVARO, 2000, a network of irregular galleries and communicating shafts. On the omission surface, the tunnels are linked to elon~' gated or winding grooves in hard or firm substrates. Further elements of the complex trace fossd include lobate bur~ rows similar to Zoophycos and Rhizocorallium, mainly occurring in firmground and softground, shallow to deep Ushaped pouches and winding tunnels (Maeandropolydora sulcans VOIGT, 1965) in hard and firm substrates. Finally, some tunnel portions and well preserved top surfaces of the ichnofabrics are scattered with the faecal pellets Coprulus oblongus MAYER, 1952. C. oblongus has a rounded shape and a homogeneous structure and belongs to the Coprulidae n. ichnofam. Based on the numerous fingerprints preserved in the complex trace fossil, polychaete worms are identified as possible tracemakers, This is in accordance with the close combination of borings and burrows, a tunnel system highly variable in shape and size, blind ending side-branches and tunnel terminations, association with scolecodonts and exceptionally preserved polychaete remains. In addition, different commensals may have contributed to the modification of the complex trace fossil.Kurzfassung: Die Spurenfossil-Gattung Balanoglossites MAGDEFRAU, 1932 wird aus ihrem Typusgebiet neu beschrieben und als Teil eines komplexen Spurenfossils, das sowohl aus Grabgang-als auch ans Bohnmgskomponenten besteht, interpretiert. Die lchnotypus-Art, B. triadicus, besteht vorwiegend aus tief angelegten U-oder Y-fOrmigen Gangelementen, wohingegen B. ramosus n. isp. aus unregelm~iBig verzweigten G/ingen aufgebaut ist. Beide Spurenfossil-Arten kommen h~iufig in Fest-und HartgrOnden mit vereinzelten Epikarst-Erscheinungen vor. Im darunterliegenden Weichgrund kOnnen sie in Labyrintichnus terrerensis UCHMAN & ALVARO, 2000 ~ibergehen, einem Netzwerk yon unregelma6igen G~ngen und Verbindungssch/ichten. An Omissionsfl/ichen sind die G/inge mit langgestreckten oder gewundenen Furchen im harten oder festen Substrat verbunden. Weitere Elemente des komplexen Spurenfossils bestehen aus lobaten Grabg/ingen/ihnlich zu Zoophy¢os and Rhizocorallium, die vorwiegend in Fest-trod Weichgdinden vorkommen, flachen bis tief angelegten U-f'rrmigen "Taschen" und gewundenen Gangen (Maeandropolydora sulcans VOIGT, 1965) im harten und festen Substrat. Einige Gangabschnitte und gut erhaltene Schichtfl/ichen am oberen Abschluss des IchnogeAges sind mit den Kotpillen Coprulus oblong-us MAYER, 1952 Oberstreut. C. oblon...

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The trace fossil Zoophycos is abundant in transgressive, shallow marine carbonates in the Middle Permian (Wordian) Khuff Formation of the Huqf‐Haushi Uplift of Interior Oman. It often occurs as part of a complex (compound) trace fossil that comprises two integrated elements: (i) irregular galleries with straight to gently curved tunnels and interconnected shafts, and (ii) simple planar to complex spreiten structures with a marginal tube (Zoophycos). The galleries are characterized by irregularly winding, dichotomous branching, large variation in shape and size and circular to elliptical vertical cross‐sections. Zoophycos consists of spreiten with a marginal tube, either originating as a simple lobe from the convex segment of a curved tunnel, or forming more complex, subcircular, spreiten systems parallel to bedding. The spreiten were formed by simple strip mining, where the animal defecated without producing faecal pellets. U‐shaped marginal tubes indicate that the burrows were well aerated. The complex trace fossil points to combined dwelling and deposit‐feeding behaviour, with irregular galleries in the firm substrate and Zoophycos spreiten in the softground below it. It can be assumed that the animal used the open tunnel system mainly for dwelling (domichnion) and possibly suspension feeding, but occasionally changed to deposit feeding while creating the spreiten (fodinichnion). The integration of the irregular galleries (tunnels and interconnected shafts) with the marginal tubes of Zoophycos suggests the same producer for this compound trace fossil. Many modern polychaetes produce very similar galleries within firm and soft substrates, and polychaetes are therefore interpreted as the most likely producers. Similarities between Permian and Triassic Zoophycos suggest comparable trace making behaviour before and after the end‐Permian mass extinction.

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