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We describe a new species of Cybocephalidae (Coleoptera) from Ethiopian Miocene amber, Pastillus aethiopicus n. sp. This is the second beetle species discovered in that fossiliferous amber deposit. It is the fourth species described in the extant genus Pastillus Endrödy-Younga and the first fossil species discovered. Pastillus is reviewed, the species diagnosed, listed, keyed, and distribution data recorded. Additionally, checklists of fossil Cybocephalidae, and African Cybocephalidae fauna are provided.

In the present paper we trace the patterns of convergent evolution of encrusting calcareous polychaetes and tentaculitoids with respect to the morphology and function of their tubes. Both clades have morphologically similar tubes. Six of the eight basic morphotypes of encrusting tubeworms occur both in calcareous polychaetes and in tentaculitoids. All six encrusting tentaculitoid tubeworm morphotypes distinguished have analogues among serpulid and sabellid polychaetes. Both tentaculitoids and polychaetes with calcareous tubes have a similar plesiomorphic morphotype, which is characterized by substrate parallel, irregular growth away from the initial point of encrustation. Dominance of similarities in the order of evolution of morphotypes in the calcareous tubeworms indicates that despite genetic differences, ecological similarities (suspension feeding) and similarities in the tube material (calcareous), as well as body plan (worm-like) had a strong control over the evolution of calcareous tubeworms. The calcareous tubeworm life modes likely appeared in the order of increasing dependence on the type of substrate. In general, possible antipredatory strategies (spines, keels, cryptic and endobiotic mode of life) of calcareous tubeworms are evolutionarily old. The plesiomorphic general hard substrate encrusters are evolutionarily the most successful and have the longest stratigraphic range both in tube-dwelling polychaetes and tentaculitoids. Innovations, such as attachment of the tube by basal projections were developed in some microconchid tentaculitoids but not in calcareous polychaetes; budding tubes occur in both taxa, however, in microconchid tentaculitoids it was a brief evolutionary event, whereas in polychaetes such pseudocolonies have a long stratigraphic range. The ability to live in brackish and fresh waters by some tentaculitoids and tube-dwelling polychaetes seems not to be associated with any particular tube morphotype.

Bromalites (coprolites, regurgitalites and consumulites) are trace fossils that preserve valuable information on their producers’ diet and feeding behaviors. Here, we report a compact skeletal mass from the Middle Triassic Xingyi Fauna of Dingxiao, Xingyi City, Guizhou Province, South China through multiple analytical methods. Using micro-CT scans, we provide 3D reconstruction of two vertebral arches, four coracoids, three ribs of three kinds, four humeri including one male and three female ones, five scapulae including two right one and three left ones of different sizes, which are inferred to be from at least three individuals of Keichousaurus hui. Bone aggregates of multiple individuals, associated with less gastric etching on bone surfaces and the absence of a phosphatic and organic matrix surrounding the bones as revealed by microstructural and chemical analysis respectively, suggest that this bone mass is a regurgitalite rather than a coprolite. The vertebrate fossils reported from the regurgitalite-bearing strata suggest that the best candidate for the potential producer of the regurgitalite are the near-shore sauropterygians Nothosaurus or Lariosaurus. The discovery of a Keichousaurus-bearing regurgitalite shed new insights on the feeding behaviors of Middle Triassic marine reptiles and the paleoecology of the Xingyi Fauna.