A new helicopsychid caddisfly, Palaeohelicopsyche marki sp. nov., is described from Eocene Baltic amber. The extinct genus Palaeohelicopsyche is now represented by three species alongside the genus Helicopsyche, with five extinct species in Baltic amber. The male of the new species is notable for its androconial head organs in the form of paired eversible tubes, a feature rarely found in males of fossil helicopsychids and apparently unknown in extant species. The structure and function of these remarkable male organs are discussed.

Temnospondyl finds rank among the most abundant remains throughout the continental Triassic deposits. In the Central European Basin, they are especially numerous, with diversity peaks in the Röt, Erfurt and Stuttgart formations. Currently, a total of 20 genera and 29 species of temnospondyls is recognized in the German Triassic. The Early Triassic temnospondyl assemblages encompass the five genera Trematosaurus, Sclerothorax, Odenwaldia, Meyerosuchus, and Parotosuchus. Trematosaurus is present with the coeval species T. brauni and T. thuringiensis whereas Parotosuchus is known with the three species P. helgolandicus, P. nasutus and the newly erected P. decumanticus n. sp. from the Black Forest from different time slices. Sclerothorax is known from two widely divergent horizons in the early and late Olenekian of Hesse, whereas Odenwaldia and fragmentarily known Meyerosuchus are from localities in the Black Forest and almost coeval horizons dating late Olenekian. In the Middle Triassic the ten temnospondyl genera Plagiosuchus, Plagiosternum, Megalophthalma, Gerrothorax, Trematolestes, Callistomordax, Eocyclotosaurus, Stenotosaurus, Tatrasuchus and Mastodonsaurus (two species) are recognized. Kupferzellia Schoch, 1997 is a junior synonym of Tatrasuchus Maryanska & Shishkin, 1996. The coeval early Anisian Eocyclotosaurus and Stenotosaurus are morphologically similar but distinct in palate features, whereas the other taxa all fall within the late Ladinian interval of the Erfurt Formation. The lost type and only specimen of “Cyclotosaurus” papilio was most consistent with the genus Eocyclotosaurus. The Late Triassic rock sequence has yielded the six valid genera Plagiosaurus, Gerrothorax, hyperokynodon, Metoposaurus, Capitosaurus and Cyclotosaurus, the latter with the five species C. robustus, C. buechneri, C. ebrachensis, C. posthumus and C. hemprichi. In the Rhaetian, reworked remains may only be referred to indeterminate plagiosaurines and capitosauroids.

Archostemata is a species-poor group of beetles. However, the morphological diversity of the group is still not completely grasped since many ingroups are only known by the adult representatives. Micromalthus debilis is often the most discussed representative of this group in literature and stands as an example of a complex and unique life cycle. The rest of the known representatives do not have such specialised life cycles. However, in many groups, only the ecology of the adults is known and the few known larvae show specialisations of softwood-borers. Here we summarise the known larvae of Archostemata and report a new fossil from Eocene Baltic amber. The new specimen shows many morphological characters known from modern larvae of Archostemata (e.g., the broad head or the distinct posteromedian indentation of the head capsule) and is highly likely a larval representative of the group, and therefore, represents the first larva of Archostemata from the Eocene. We also study and discuss two additional unidentified fossil specimens with similar body outlines originating from Cretaceous Myanmar amber. Additionally, we analysed all the available specimens with quantitative methods, both fossil and modern, new and from literature.

We report a well-preserved complete male specimen of Tethyranina propinqua (Ristori, 1891) (Raninidae De Haan, 1839) from the Early Pleistocene of the surrounding area of Orvieto (Terni, Umbria, central Italy). This new record allows to describe for the first time the male morphological characters of this species known to date by female specimens only, updating the anatomical description and diagnosis of this species.

The moderately rich ammonite assemblage of the distractum Biohorizon is described from the Lambertiknollen Bed, a set of phosphatic concretions layers in the upper part of the Callovian Ornatenton Formation of SW Germany. The distractum Biohorizon is dominated by the highly variable Subboreal species Quenstedtoceras lamberti (Sowerby, 1819), the index ammonite of the Middle Jurassic Lamberti Zone. In addition, there are several species of Submediterranean oppeliids besides Submediterranean aspidoceratids, peltoceratids, perisphinctids, and Subboreal kosmoceratids. Tropical faunal elements such as lytoceratids and phylloceratids did not reach the area during this time interval. After a short hiatus indicated by an intercalated belemnite breccia, another layer with phosphatic concretions follows. It contains mostly reworked and fragmented ammonites of the newly introduced aff. zudacharicum Biohorizon, which is the youngest biohorizon of the Lamberti Zone in the Swabian Jurassic. Despite the presence of Submediterranean taxa, the ammonitic assemblages have a rather Subboreal character. This Subboreal character of the ammonite assemblages as well as the great abundance of phosphatic concretions, clay sedimentation and glauconite formation points to rather cold seawater temperatures at least at the seafloor probably caused by upwelling. A comparison of the two succeeding ammonite assemblages points to an increased cooling trend towards the Callovian-Oxfordian boundary.

In most tooth-bearing bony fishes and tetrapods tooth renewal starts with the resorption of the tooth root or the mineralized tissue with which the tooth is anchored to the jawbone. The tooth is finally shed and replaced by a new one. In elasmobranchs, the teeth are not firmly attached to the jaw cartilage, but to a membrane of connective tissue that migrates together with the teeth in the direction of the edge of the jaw. After use, a tooth is shed and replaced by the one that follows. This only requires breaking down the collagen fibres that connect the tooth root to the membrane, the root does not need to be resorbed. Thus, shed elasmobranch teeth are mostly completely preserved in their entirety. In contrast, most isolated found hybodont teeth lack the root (90 to 100%). Although this unusual kind of preservation has been known since the time of Agassiz (1843), the cause of this phenomenon has not been clearly explained until now. Here it is demonstrated that the resorption of the tooth root is a plausible explanation for these observations. Tooth shedding in hybodonts happened, therefore, most probably in a similar way to that of most non-chondrichthyan vertebrates, but with one difference. In bony fishes and tetrapods, the dentine of the tooth root is resorbed by multinucleated osteoclasts, which produce characteristic traces on the dentinal surface (Howship's lacunae). These lacunae are usually well preserved on fossil shed teeth, but they could not be traced on the basal face of hybodont tooth crowns. Most probably in hybodonts mononucleated instead of multinucleated osteoclasts effected resorption. Unfortunately, these smaller cells do not leave distinct resorption traces on the dentinal surface. Within the elasmobranchs, tooth root resorption during tooth renewal is obviously a unique character of the Hybodontiformes and further evidence for the monophyly of the group. The feature can be observed throughout the full geological history of the group, from the earliest Carboniferous to the end of the Cretaceous when the hybodonts became extinct. Altogether, resorption is documented here in 36 genera with 162 species plus several species in open nomenclature. All species suspected to be hybodonts but which clearly did not resorb the tooth root must be excluded from this group. For species from which only skeletons are known, or whose teeth are insufficiently described and figured, further studies of isolated teeth are required to determine the mode of tooth replacement.