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Several thousand disarticulated remains together with a few complete enrolled specimens of the lower Cambrian eodiscoid trilobite Calodiscus lobatus (Hall, 1847) have been collected at two outcrop areas in Sweden. The material reveals new details of morphology and morphogenesis during ontogenetic development. Size-frequency analyses show that the material from the Fånån rivulet in Jämtland, central Sweden, represents a natural population dominated by juveniles, whereas the material from Gislövshammar in Scania, southern Sweden, has been sorted during postmortem transport. Three stages of protaspid development can be traced and defined as well as all subsequent ontogenetic stages for the cephalon, hypostome and pygidium. The early meraspid pygidium has a pronounced larval notch, which persists, though becoming progressively less distinct in later meraspides. The number of axial rings in the transitory pygidium increases throughout meraspid development until a third and final thoracic segment is liberated. During ontogeny the articulating half-rings are strongly developed, and both meraspides and holaspides were capable of full sphaeroidal enrollment and outstretched postures. The hypostome undergoes some dramatic modifications; in M0 the anterior margin is axe-shaped, by M1 the area of attachment greatly decreases and the hypostome becomes more elongated and pear-shaped, before attaining its adult form, which has an overall resemblance to that of polymerid trilobites. During ontogeny, the hypostome changes from a conterminant attachment to a natant condition, thereby mirroring hypostomal evolution within trilobites generally. The morphology, ontogeny, enrollment, hypostomal development and the presence of calcified protaspides suggest polymerid rather than agnostoid affinities of the eodiscoids.

A lower Cambrian eodiscoid trilobite fauna and an associated holmiid trilobite,Holmiasp., are described from a bioclastic limestone at the top of the Torneträsk Formation in the Luobákti section, south of Lake Torneträsk, northern Sweden. Other associated polymerid trilobites includeOrodes?lapponicaandStrenuaeva inflata. The precise age of the trilobite fauna cannot be determined, but its generic composition and stratigraphical position at the top of the lower Cambrian suggest that it was recovered from theOrnamentaspis?linnarssoniAssemblage Zone. Two species of eodiscoids are present:Neocobboldiaaff.dentataandChelediscus acifer. The latter species is known previously from England and southeastern Newfoundland, and provides a novel link between upper lower Cambrian successions in Baltica and Avalonia.

Shallow marine, nearshore strata of earliest Campanian (Gonioteuthis granulataquadrata belemnite Zone) and latest Early Campanian (informal Belemnellocamax mammillatus belemnite zone) age in the Kristianstad Basin, southern Sweden, have yielded isolated leptoceratopsid teeth and vertebrae, representing the first record of horned dinosaurs from Europe. The new leptoceratopsid occurrence may support a European dispersal route for the Leptoceratopsidae, or may represent an entirely endemic population. The presence of leptoceratopsid teeth in shallow marine deposits contradicts previous hypotheses suggesting that basal neoceratopsians mainly preferred arid and ⁄ or semi-arid habitats far from coastal areas.

Three thousand seven hundred disarticulated remains together with several articulated specimens of the Cambrian Series 2 ptychopariid trilobite Strenuaeva inflata Ahlberg and Bergström, 1978 have been collected from the Torneträsk area, northern Sweden. The material provides significant new data on the morphology, ontogeny, moulting and enrolment of the species. Two distinct morphotypes, possibly an expression of sexual dimorphism, are recognized. The morph with a pair of bulbs in the frontal area, interpreted as brood pouches, is considered to represent females. Statistical treatment of the length ⁄ width ratio in cranidia reveals isometric growth during ontogeny for both morphotypes. The transition from the meraspid to holaspid ontogenetic period has been established through recognition of the successive development of the number of thoracic segments in articulated late meraspides. Throughout its life cycle, S. inflata went through 11 meraspid degrees and at least 17 holaspid growth stages. Inferred moult ensembles and exuviae reveal the successive opening of cephalic sutures and the function of the rostral plate during exuviation. As in other ellipsocephalid trilobites in which enrolment is known, the pygidium and two or three thoracic segments of S. inflata are concealed beneath the cephalon (spiral enrolment) during complete enrolment.

The latest early Campanian archipelago deposits of the Kristianstad Basin, southern Sweden, yield one of the most diverse Cretaceous chondrichthyan faunas collected from a narrow stratigraphical interval. Building on previous descriptions of various selachians, squatiniform and synechodontiform sharks are added to the faunal list. Squatinidae is represented by Squatina (Squatina) lundegreni sp. nov. and Squatina (Squatina) fortemordeo sp. nov. The poorly preserved type specimens of the nominal Squatina hassei from the Maastrichtian of The Netherlands were recently regarded conspecific with better preserved Santonian–Maastrichtian teeth of Squatina (Cretascyllium) from the Anglo-Paris Basin. This appears to have been based largely on the assumption that the nominal S. hassei was the only Squatina present in NW Europe during the Santonian–Maastrichtian. The Swedish material indicates a greater diversity of squatinoids, and the nominal S. hassei is here regarded as a nomen dubium of uncertain subgeneric affinity. Two types of synechodontid teeth with a tall central cusp co-occur in the Campanian of the Kristianstad Basin. Based on articulated jaws of the markedly dignathic S. dubrisiensis from the Cenomanian of England, the two morphs are regarded as upper and lower anterior teeth of the single species S. filipi sp. nov.

Three species of bradoriid arthropods from the lower to middle Cambrian transitional interval of Scania, southern Sweden, are described and illustrated: Beyrichona tinea from the top of the traditional lower Cambrian (Gislöv Formation; Ornamentaspis? linnarssoni Zone), and Hipponicharion eos and Alutella sp. from the basal portion of the traditional middle Cambrian (lowermost part of the Alum Shale Formation). The bradoriid fauna compares most closely with others previously described from western and eastern Avalonia (New Brunswick and England). The record of B. tinea suggests a correlation between the "Protolenus Zone" (Hupeolenus Zone) of western Avalonia and the O.? linnarssoni Zone of Scandinavia. Hipponicharion eos appears to be a fairly long−ranging species as it has previously been recorded from upper lower Cambrian or lower middle Cambrian strata in New Brunswick, Poland, and probably Sardinia. The record of H. eos from the lowermost part of the Alum Shale Formation suggests that this largely unfossiliferous interval in the Scanian succession is not younger than the Acadoparadoxides oelandicus Superzone. The genus Alutella has not previously been recorded from the Acado−Baltic Province.

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