A synoptic analysis of previously published material and new finds reveals that Himalayan Cambrian brachiopods can be referred to 18 genera, of which 17 are considered herein. These contain 20 taxa assigned to species, of which five are new:

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The oldest assumed ostracods appear in the fossil record from the Tremadocian Paltodus deMfer conodont Biozone. Although geographically widespread these early ostracods have no obvious Cambrian antecedents. Their first appearance at ca. 485 Ma contrasts with molecular evidence that suggests a much earlier (latest Proterozoic or Cambrian) origin for ostracods. Some Cambrian bivalved arthropods such as Altajanella and Vojbokalina, conventionally referred to the Bradoriida, have carapace morphologies that resemble Ordovician palaeocopid ostracods, though such a relationship is unproven without soft part anatomy. Evidence from preserved soft anatomy demonstrates that Bradoriida, such as Kunrningella, and Phosphatocopida, essentially the Cambrian 'ostracod' record of traditional usage, belong outside the Eucrustacea. Early Ordovician ostracods appeared first in shallow marine, oxygenated environments on shelf margins, in a similar setting to other elements of the 'Paleozoic fauna'. "Iheir biodiversity was low (3 named genera and ca. 12 species), though some taxa such as Nanopsis and Eopilla achieved widespread dispersal between major Ordovician palaeocontinents. As bradoriids were largely extinct by the Late Cambrian, ostracods do not appear to have directly competed with them for shalIow marine environments. The rapid colonisation of these settings by ostracods may have been Ÿ by the available ecospace vacated by Bradoriida.