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Systematic collecting through the upper Wenlock (upper Homerian) and lower Ludlow (Gorstian and lowermost Ludfordian) Silurian rock succession of the Long Mountain, Powys, Wales, identifies some 48 chitinozoan species that distinguish four biozones, two subzones and an interregnum. Consideration of the chitinozoan biozones together with those of the graptolites enables a local three-fold subdivision of the late Homerian lundgreni graptolite Biozone, and the distinction of lower and upper intervals for the Gorstian incipiens graptolite Biozone. The base of the Ludlow Series in the Long Mountain more or less equates to the base of the Cingulochitina acme chitinozoan Biozone, although no key chitinozoan first or last appearance datums are associated with the series boundary itself. The new graptolite-chitinozoan biozonation allows enhanced correlation between upper Wenlock and lower Ludlow sedimentary deposits of the Lower Palaeozoic Welsh depositional basin and those of the palaeo-shelf in the stratotype Wenlock and Ludlow areas of Shropshire. Chitinozoans seem affected by the phenomena that caused the late Wenlock 'Mulde extinction' in graptolites but, with the final disappearance of 9 species and re-appearance of 11 species following an interval of overall low diversity, they seem to have suffered less severely than their macro-zooplanktonic contemporaries

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A restudy of the palynology of the Whirlpool Formation and Power Glen Formation in New York (USA) yielded a diverse fossil assemblage with cryptospores, glomalean fungi, acritarchs, chitinozoans, scolecodonts, and small carbonaceous fossils. These new data, and particularly the presence of the chitinozoan index fossil Hercochitina crickmayi, combined with emerging stable carbon isotope data, suggest a Late Ordovician (Katian or Hirnantian) age for these formations, which is older than their previously suggested Silurian (Rhuddanian) age

The Silurian of Australia contains at least three genera (one new, Canalarta gen. nov.) and three species (two new, Canalarta papata sp. nov. and Bolbozoe beccata sp. nov.) of myodocope ostracods. These fossils were recovered from clastic sedimentary deposits in the lower Silurian (probably Homerian) Walker Volcanics unit of New South Wales that may represent mudflow deposits. In having the youngest occurrence of Entomozoe aff. tuberosa and the oldest known Bolbozoe species, the Australian myodocopes represent a chronologically intermediate assemblage between previously known early and late Silurian myodocope faunas. Several fossil groups from the Silurian of Australia, such as ostracods, trilobites, brachiopods and corals, apparently have a cosmopolitan distribution at generic level. The presence of many continental and micro-continental landmasses that existed along and within the tropical pan-Tethyan seaway, together with the prevailing ocean circulation, could explain this distributional pattern. The depositional setting, sedimentary deposits and faunal associates do not provide conclusive evidence concerning the lifestyle of the Australian myodocopes. They could represent nektobenthic species, as has been suggested for other early to mid Silurian myodocopes, or hyperbenthic/pelagic species, as was proposed for known late Silurian forms