ABSTRACT: To test the hypothesis that pelagic larval duration (PLD) plays a role in the longitudinal dispersal of reef fishes, we examined the relationship between PLD and occupancy of oceanic islands among tropical eastern Pacific (TEP) snappers (Lutjanidae). We estimated PLD from analysis of the otolith microstructure of juveniles collected at 2 localities from the Pacific coast of Colombia. Otoliths had a distinct 1increment settlement transition, along which increment width gradually decreased in 1 species examined (Lutjanus guttatus). PLD estimated from lapilli was relatively short (21.8 to 24.4 d) and invariant (3.1 to 9.6% coefficients of variation [CV]) in L. argentiventris, L. guttatus, L. novemfasciatus, and Hoplopagrus guntheri, but was relatively long in L. viridis (37.9 d, CV = 8.6%). Mean PLD was not correlated with the largest distance between any 2 localities occupied but was positively correlated with number of oceanic islands occupied. Consideration of the geographic isolation of each island improved the strength of the latter relationship. However, these patterns were largely due to L. viridis, which was present in all oceanic islands, including Clipperton Atoll, the most isolated island in the TEP. This study suggests that the longitudinal component of species' ranges (measured by occupancy of reefs around oceanic islands) reflects dispersal abilities, yet overall range size is independent of PLD because other factors determine other components of geographic range.
KEY WORDS: Early life history · Geographic range size · Lutjanidae · Otolith microstructure · Pelagic larval duration · Reef fishes
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