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Isopods are one of the key marine groups that radiated extensively in the southern high-latitude regions, and it is widely assumed that they did so essentially through the Cenozoic era. Nevertheless, palaeontological evidence is now beginning to accumulate which suggests that some at least of the key isopod taxa may be of considerably greater antiquity. In particular, Schweglerella strobli Polz from the Early Tithonian Plattenkalk of Solnhofen, southern Germany indicates that the suborder Sphaeromatidea is of at least Late Jurassic ancestry, and possibly much older.

• Read more about Late Jurassic Tethyan ancestry of Recent southern high-latitude marine isopods (Crustacea, Malacostraca)

The middle Ordovician brachiopod faunas of Kazakhstan provide one of the most complete records of the evolution and radiation of some of the oldest known spire-bearing brachiopods. By contrast with North American faunas, Kazakhstanian atrypide taxa mostly belong to the suborders Atrypidina and Lissatrypidina, whereas the suborder Anazygidina is completely absent. Kazakhstanian species referred previously to ZygospiraKuzgunia are reassigned to Sulcatospira, which appeared in the Caradoc Diplograptus multidensClimacograptus clingani biozones (Sulcatospira? praecursor and Sulcatospira prima sp.

• Read more about The earliest atrypides and athyridides (Brachiopoda) from the Ordovician of Kazakhstan

Data from the monographic literature indicate a general size reduction amongst Bathonian marine bivalves in southern England: mean size is reduced in all subclasses and major mode-of-life categories relative to the immediately preceding Bajocian stage (27 per cent. reduction) and the later Oxfordian stage (41 per cent. reduction). Smaller size cannot be explained in terms of sedimentary facies, nor as a 'pure' evolutionary phenomenon (involving no environmental change); it therefore probably reflects some quality of the ambient water. A comparable reduction in average size (19 per cent.

• Read more about Evidence and cause of small size in Bathonian (Middle Jurassic) marine bivalves of north-western Europe

Some encrusting cheilostome bryozoans etch a pattern of small pits into hard calcareous substrates, especially calcitic and aragonitic shells of molluscs. These patterns, herein described as Leptichnus ichnogen. nov., comprise pits which are sub-circular to elongate in cross section and are found in either uniserial (L. dromeus isp. nov.) or multiserial arrangements (L. peristroma isp. nov., the type species). Each pit corresponds to the location of a single zooid in the bryozoan colony.

• Read more about A new ichnogenus for etchings made by cheilostome bryozoans into calcareous substrates

A new troglobitic sigillid genus, Kasella, is found in the submarine caves of the Ryukyu Islands. Sigillids are primitive podocopid ostracods having ancient characters such as unequal valves and many small adductor muscle scars. Kasella is possibly derived from the sigillid Cardobairdia, a deep-sea muddy bottom inhabitant, or its relatives. Submarine caves are characterized as both 'safe places', where biological factors such as competition and predation are reduced, and as 'crypts', representing dark and oligotrophic environments.

• Read more about A new sigillid ostracod from submarine caves of the Ryukyu Islands, Japan

A revision of the temnospondyl chigutisaurids from the Upper Triassic of Argentina is presented. The validity of the taxa originally proposed is discussed in the light of new material. The genus Pelorocephalus (Chigutisauridae) is diagnosed by the presence of a longitudinally keeled cultriform process, occurrence of the anterior Meckelian fenestra on the suture between splenial and postsplenial, location of the chordatympanic foramen on the contact between angular and prearticular, and exposure of the angular on the lingual mandibular surface. Three species, Pelorocephalus mendozensis, P.

• Read more about Chigutisaurid amphibians from the Upper Triassic of Argentina and their phylogenetic relationships

Albanerpeton arthridion is rediagnosed and redescribed based on jaws, frontals, atlantes and humeri from the Lower Cretaceous (uppermost Aptian–middle Albian), Antlers Formation of Oklahoma and Texas, USA. Frontals described herein for the first time for A. arthridion confirm that the species belongs in the type genus Albanerpeton, making it the geologically oldest reported member of the genus. A. arthridion is interpreted as the most primitive species of Albanerpeton and to have been relatively small.

• Read more about The amphibian Albanerpeton arthridion and the Aptian–Albian biogeography of albanerpetontids

A new subfamily, genus and species of Dasyuridae is described on the basis of exceptionally well preserved material from the Miocene of Riversleigh, north-west Queensland. Specimens include the only pre-Pleistocene crania known for the family. Barinya wangala gen. et sp. nov. (Barinyainae subfam. nov.) is the geologically oldest taxon that can be placed within Dasyuridae on the basis of synapomorphies that are unequivocal within Dasyuromorphia. Four derived cranial features present in Barinya wangala are shared only with modern Dasyuridae among dasyuromorphians.

• Read more about The geologically oldest dasyurid, from the Miocene of Riversleigh, north-west Queensland

The first middle Ordovician bivalve fauna to be described from Britain is from the lower part of the Didymograptus murchisoni Biozone of the Llanvirn Series of the Builth-Llandrindod Wells Inlier of mid-Wales. The fauna is preserved in a close inshore facies that accumulated locally around volcanic islands and is incorporated in bivalve-dominated shell-beds, some of which form true bivalve coquinas. The fauna is dominated numerically by palaeoheterodonts (including a single modiomorphoid species), but also includes several species of palaeotaxodonts.

• Read more about Middle Ordovician bivalves from Mid-Wales and the Welsh Borderland

We briefly review the various types of feeding habits in marine arthropods, and suggest that the trilobites adopted a range of different feeding strategies. We show that much of the variety of trilobite exoskeletal development, particularly in the cephalon, can be explained as a response to the adoption of specific feeding modes. We regard the primitive mode as having been predatory/scavenging, both from morphological grounds and by out-group comparison, but this habit had a long subsequent history in the group.

• Read more about Feeding habits in trilobites