Diverse Lophoctenium burrows from the Upper Devonian (Famennian V and VI) of Algeria

Three ichnospecies of Lophoctenium (L. comosum, L. richteri and L. cf. haudimmineri) are reported from the Upper Devonian Argiles de Marhouma Formation (southwestern Algeria) for the first time. This formation contains a diverse assemblage of trace fossils belonging to the Nereites ichnofacies. We describe three ichnospecies of Lophoctenium that correspond to three different feeding strategies among the diverse ichnofauna of the Argiles de Marhouma Formation. The strategy of L. comosum evidences food-rich sediments as it maximises the amount of collected food per foraged distance. The strategy of L. richteri is probably most efficient for feeding in slightly less nutrient rich sediment, but gives the opportunity to discover more prolific feeding sites by moving on longer distances. The strategy with a straight central burrow and probes on both sides of the main burrow with long interspaces (L. cf. haudimmineri) was presumably used in the least food rich sediment. It seems that the Lophoctenium was widespread in the Devonian, but restricted to seas surrounding Gondwana.