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A new tessellated heterostracan, Aporemaspis pholidata gen. et sp. nov., is described from the Snowblind Bay Formation of Cornwallis Island in the Canadian Arctic Archipelago. Its age is late Lochkovian, and it is thought to be related to other tessellated forms from the Delorme Formation, District of Mackenzie, NWT. Two fragments of armour from the Delorme Formation are tentatively assigned to Aporemaspis gen. nov.

• Read more about A new agnathan from the Lower Devonian of Arctic Canada, and a review of the tessellated heterostracans

Cuticles from seven taxa of neuropterid frond are described. Based on these and earlier descriptions, four main groups of species are recognized within Neuropteris Brongniart: Group I - N. loshii Brongniart, N. tenuifolla Sternberg and N. rarinervis Bunbury; Group II - N. ovata var. simonii (Bertrand), N. ovata var. sarana (Bertrand), N. ovata var. aconiensis nov. var., N. flexuosa Sternberg and N. schaeferi Doubinger and Germer; Group III - N. scheuchzeri Hoffmann, N. macrophyllu Brongniart, N. subauriculata Sterzel, N. britannica (Gutbier), N. sp alpha Barthel and N.

• Read more about Epidermal structure of some medullosan Neuropteris foliage from the middle and upper Carboniferous of Canada and Germany

New stratigraphic evidence and systematic revision, including the designation of types where necessary, establish unambiguously the definitions and precise ages of a number of classical species of ammonites which, although in part rare in this country, are of great importance in understanding the evolution of the Boreal and Sub-boreal families Cardioceratidae and Kosmoceratidae. They include Pseudocadoceras boreale Buckman, 1918, Chamoussetia funifera (Phillips, 1829), Chamoussetia phillipsi = nom. nov.

• Read more about Cardioceratid and kosmoceratid ammonites from the Callovian of Yorkshire

Phylogenetic analysis of the extinct anthozoan clade Tabulata yields new hypotheses concerning their pattern of diversification in the Ordovician. Two separate phylogenetic analyses, one based on primitive rugose corals as the outgroup (RUGSGRPS), and the other based on Lichenaria as the ancestral tabulate coral (LICHGRPS) yielded different phylogenies. The phylogenies generated are broadly different from previously proposed phylogenies based on possibly subjective morphological interpretations, and on biostratigraphical and/or biogeographical hypotheses alone.

• Read more about Phylogenetic analysis of the early tabulate corals

Diagenetic and morphological studies of transversely sliced rostra of six belemnite species were carried out by means of scanning-electron, cathodoluminescence and blue-light fluorescence microscopy, staining of thin sections, total organic content analysis, as well as x-ray diffractometry. Diagenesis has not destroyed the laminar morphology of rostra in most cases, and diagenetic alterations indicate that the original mineralogy was low-Mg calcite.

• Read more about Diagenesis and construction of the belemnite rostrum

The genus Clonograptus is redefined as a form genus consisting of one phylogenetically based subgenus, Clonograptus s.s., and additional species of uncertain relationships. Clonograptus is transferred from the Anisograptidae to the Dichograptidae, since bithecae are absent along the stipes in the type species. Temnograptus, Herrmannograptus, Anthograptus, and ?Calamograptus are considered synonyms of Clonograptus s.s., based on a large fauna of 'Temnograptus' multiplex that shows extreme variation, especially in stipe length.

• Read more about Intraspecific variation and relationships of some Lower Ordovician species of the dichograptid, Clonograptus

The earliest nowakiid known to date, from the Llandovery Atavograptus atavus Zone of central Wales, is described as Nowakia gwyensis sp. nov. If the new form and the slightly younger Nowakia brevis are true nowakiids, the origins of the Dacryoconarida must now be sought in the earliest Silurian or older deposits.

• Read more about An early record of probable nowakiid tentaculitoids from Wales

The forewing of a fossil aphid Siphonophoroides? orapaensis (Homoptera: Aphididae) is described. It is the first fossil aphid from Africa. Although it is impossible to assign it with confidence to a distinct extant or extinct family of the Aphidoidea, it has been placed tentatively in the Drepanosiphidae. Its similarity with members of the genus Siphonophoroides had led to its tentative inclusion in this group. The fossil was discovered in middle Cretaceous sediments from the Orapa Diamond Mine, Botswana.

• Read more about A new aphid from the Cretaceous of Botswana

The earliest development of coral-bearing strata in Central Saudi Arabia took place during deposition of the Tuwaiq Mountain Limestone (upper Middle-Upper Callovian). It does not appear to constitute a major barrier reef, but rather a series of isolated corals and coral biohcrms; coral heads (20-50 cm in diameter) are scattered in life position within an extensive sheet of pure limestone (20^1-0 m thick) stretching for more than 1000 km along strike in Central Saudi Arabia. This sheet could be described as an extensive biostrome.

• Read more about Callovian colonial corals from the Tuwaiq Mountain Limestone of Saudi Arabia

The structure, mode of growth, and possible function of the spiniform tubercles of the Upper Jurassic ammonite Aspidoceras are described and analysed. Their complex growth pattern is particularly suitable for the construction of long, delicate, hollow spines. These spines probably contained extensions of the mantle, which were in contact with the environment through openings at their tips. Their function is thus inferred to have been primarily sensory.

• Read more about Growth and function of spines in the Jurassic ammonite Aspidoceras