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The Aulacopleuridae and Otarionidae are considered to be synonymous. The composition and phylogeny of the family are discussed, and new family, subfamily, and generic diagnoses given.

• Read more about A review of the trilobite family Aulacopleuridae

Coral ecosystems are considered by many biologists to have been stable over ecological and evolutionary time, yet the Pleistocene history of reefs reveals complex and large-scale habitat changes associated with glacio-eustatic rise and fall of sea-level. Study of the molluscan assemblages from three Pleistocene rock units, together with faunas from Recent habitats on Aldabra Atoll, shows that shallow-water habitats and the associated communities have changed considerably during the period of the late Pleistocene.

• Read more about Faunal response to the instability of reef habitats: Pleistocene molluscan assemblages of Aldabra Atoll

Regular colour markings on a specimen of Asteroceras stellare (J. Sowerby) are compared with the tuberculation known within this species.

• Read more about Unusual pattern preservation in a Liassic ammonite from Dorset

The first articulated specimen of Namuropyge acanthina (Coignou, 1890) is described from the Visean of Treak Cliff, Derbyshire. This specimen confirms that cephala described as Coignouina Reed, 1943 and pygidia described as Namuropyge R. and E. Ritcher, 1939 are congeneric.

• Read more about Synonymy of the Carboniferous trilobites Namuropyge and Coignouina

Pseudotissotia (Pseudotissotia) inopinata sp. nov. is described from the Upper Cenomanian phosphatic Calycoceras naviculare/Eucalycoceras pentagonum Zone fauna of Division C of the Cenomanian Limestone of Shapwick Grange, Devon. It is the earliest occurrence of the otherwise exclusively Turonian genus Pseudotissotia Peron, 1897, and the Turonian to Coniacian Family Tissotiidae Hyatt, 1900. The family is otherwise unknown in the Cretaceous of the United Kingdom.

• Read more about The earliest tissotiid ammonite

Observations show that an inorganic sedimentary encrustation may be built up on plant leaves within a few weeks after entry into a depositional environment. Such an encrustation may be the basis of a detailed impression fossil. SEM examination and X-ray microanalysis of this encrustation on freeze-fractured, freeze-dried leaves reveals preferential deposition of fine-grained, iron-rich material that faithfully replicates the epidermal surface detail of the leaf.

• Read more about The pre-depositional formation of some leaf impressions

During the Mesozoic Era, the Trigoniidae became the dominant family of shallow-burrowing bivalves of near-shore marine habitats. Several bizarre morphological features make this the most unusual large family of burrowing bivalves ever to have existed. Forming a coadapted complex, these features enabled Mesozoic trigoniids to burrow with great efficiency, which largely accounts for their evolutionary success. Their adaptive zone included numerous niches in habitats characterized by coarse, shifting substrata.

• Read more about Coadaptation in the Trigoniidae, a remarkable family of burrowing bivalves

Dinomischus isolatus gen. et sp. nov. is described from the Burgess Shale (Middle Cambrian). A calyx, supported by a long slender stem, bears distally a circlet of elongate bracts which may have been used in filter feeding. Within the calyx a recurved gut with enlarged stomach is supported in a spacious body cavity by suspensory fibres. A sessile mode of life comparable to that of the modern pennatulacean Umbellula (Cnidaria) is proposed. Certain similarities with other stalked animals, especially the Entoprocta, exist. The actual affinities of D. isolatus remain, however, uncertain.

• Read more about A new entoproct-like organism from the Burgess Shale of British Columbia

Encrinurus variolaris (Brongniart) from the Wenlock of the Welsh Borderland is redescribed and related species discussed. Of these, E. diabolus from the Llandovery of Shropshire and E. rosensteinae from the Ludlow of the Welsh Borderland are new. The genus Frammia is restricted to F. arctica (Salter) and F. rossica (Maksimova).

• Read more about The Silurian trilobite Encrinurus variolaris and allied species, with notes on Frammia

The alga, Powysia bassettii gen. et sp. nov., is described from the early Ludlow Series at Llangammarch Wells, Powys, mid Wales. The most complete specimen consists of a thallus differentiated into holdfast, stipe, and much branched distal region, all of which appear to have a tubular construction. Reproductive structures have not been found. Comparison is made with living and fossil algae, but the precise affinities of these Welsh fossils, in which a thallus of such marked morphological differentiation has an apparently simple internal structure, remain unresolved.

• Read more about A new non-calcified alga from the upper Silurian of mid Wales