The time spent by larvae in the water-column before they settle, (pelagic larval duration, PLD), can be considered a predictor of dispersal capacity. Accordingly, populations of species with a long PLD should be more connected than those with a short PLD for the same spatial-scale.   However, other factors (e.g. currents, habitat availability) can affect and/or override life history considerations negating any predictive capacity inferred from PLD.  In this study, the genetic structure/connectivity (using CO1 and microsatellites) between populations of two species of urchins, Heliocidaris tuberculata (11 populations) and H. erythrogramma (27 populations), with very differing PLD’s (30 days vs 4 days, respectively) is investigated. Despite producing larvae with a long PLD, H. tuberculata has a very restricted distribution in Australia (NSW coast only), but is also found in New Zealand. Paradoxically, H. erythrogramma despite producing larvae with one of the shortest larval durations of any echinoderm, has a much wider distribution in Australia (NSW to Western Australia, and Tasmania), but is endemic. Examination of genetic connectivity (microsatellites) between populations from NSW, TAS & SA for H. erythrogramma reveal that populations within each of these regions are interconnected, but regions are genetically distinct (F_CT=0.21), which is supported by C01. These patterns correspond with expectations based on currents but at a much broader-scale than would be predicted by PLD alone. No evidence of phylogenetic or population divergence (F_ST=0.001) was found between populations of H. tuberculata across its distribution, indicating gene flow is maintained across considerable distances and where habitat is patchy. These results suggest that a short PLD doesn’t hinder dispersal where habitat is continuous and instead currents are driving broad-scale patterns. Correspondingly, for species with a long PLD, currents play a fundamental role in maintaining gene flow across considerable spatial scales.