‘Slow science’ approaches to understanding the ecology, natural history and demography of species have declined over recent decades, despite the critical importance of these studies to conservation biology. With the progression of the Anthropocene, populations of invertebrates are under increasing pressure across the globe, yet few long‐term datasets exist to track potential changes or declines. Here, we present a newly developed ‘slow science’ study system, to understand the demography, biology and molecular ecology of a potentially threatened species of giant idiopid trapdoor spider from inland eastern Australia. This previously undescribed species in the tribe Euoplini, here newly described as Euoplos grandis Wilson & Rix sp. nov., has a highly fragmented distribution in the southern Brigalow Belt bioregion of south‐eastern Queensland, in a landscape largely cleared for cropped agriculture. The conservation significance of Idiopidae has long been recognised, and these spiders remain a flagship group for terrestrial invertebrate conservation in Australia. By studying growth rates, life spans, recruitment, natural history, fitness, gene flow, dispersal and other aspects of population and individual health, we aim gradually to uncover the population dynamics of a discrete natural population. In this paper, we summarise longitudinal data for 69 individual trapdoor spiders following an initial 18 months of study, and highlight preliminary demographic trends, biological observations and avenues for future genetic research. Ultimately, the aim of this study is to provide a baseline dataset for the conservation of Australian Idiopidae, and a guiding case study for similar taxa elsewhere in Australia.