Balanoglossites Mägdefrau, 1932 from the middle triassic of Germany: part of a complex trace fossil probably produced by burrowing and boring polychaetes

Abstract

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...

Trace fossils from the Lower Muschelkalk of Raciborowice Górne (North Sudetic Synclinorium, SW Poland) and their palaeoenvironmental interpretation

“…Baucon and Felletti (2013b) described Archaeonassa from the Holocene of Italy. 1999;Knaust 2007aKnaust , 2008. According to Knaust (2008Knaust ( , 2010a, sipunculans (peanut worms) and polychaetes (eunicid-like polychaetes) are more probable tracemakers, as enteropneusts (acorn worms) are not typical bioeroders (see also Jaglarz and Uchman 2010).…”

“…1999;Knaust 2007aKnaust , 2008. According to Knaust (2008Knaust ( , 2010a, sipunculans (peanut worms) and polychaetes (eunicid-like polychaetes) are more probable tracemakers, as enteropneusts (acorn worms) are not typical bioeroders (see also Jaglarz and Uchman 2010). This ichnotaxon involves burrow system at the transition between firmgrounds and hardgrounds (Knaust and Costamagna 2012) and is a common component of the Glossifungites and Trypanites ichnofacies (Knaust 2008).…”

“…This ichnotaxon involves burrow system at the transition between firmgrounds and hardgrounds (Knaust and Costamagna 2012) and is a common component of the Glossifungites and Trypanites ichnofacies (Knaust 2008). B. triadicus appears not only as burrows but also as borings (Knaust 2008(Knaust , 2010bDesai and Saklani 2012). Recently, MacEachern et al (2012) and suggested that it characterizes mainly the Glossifungites ichnofacies.…”

Lower Devonian trace fossils and their paleoenvironmental significance from the western Yangtze Plate, South China

“…Common. Discussion: The constrictions and narrower blind branches are the main differences from Thalassinoides (Knaust, 2008;Jaglarz and Uchman, 2010). ?Balanoglossites cooccurs with Zoophycos, Chondrites, and Palaeophycus in the fine-grained sandstones (Bed 91) of the Yangmaba Formation and is considered to be formed in a relatively quiet offshore environment near a storm-wave base after several storm events in the Early Devonian (Zhang, 2014).…”

Middle Devonian invertebrate trace fossils from the marginal marine carbonates of the Zachełmie tetrapod tracksite, Holy Cross Mountains, Poland

“…-The ichnogenus Balanoglossites is a relatively complex trace fossil. It contains mainly U-or Y-shaped tunnels connected by shafts that record both burrowing and boring trace-maker action (Knaust 2008). The constrictions and narrower blind branches of the Zacheł-mie specimens are the main differences to Thalassinoides isp.…”