First Record and Description of Panulirus pascuensis (Reed, 1954) First-Stage Phyllosoma in Plankton of Rapa Nui

Among the most striking crustaceans from Rapa Nui Island (27° S, 109° 22′ W) is the endemic lobster Panulirus pascuensis, commonly known as the spiny lobster. This species is also present in Pitcairn Island and the Salas y Gómez Ridge. Larvae of this species pass through different phyllosoma stages until metamorphosis, during which they molt to a puerulus, a transitional stage adapted to benthic life. This species is an important fishery resource for inhabitants of Rapa Nui. However, there are several gaps in biological knowledge of this species, including its ontogeny. We sampled zooplankton to obtain first-stage P. pascuensis phyllosoma during three oceanographic campaigns around Rapa Nui (April 2015, September 2015, and March 2016). Individuals were encountered between the surface and 200 m depth with an abundance of 1.3 indiv./1,000 m3. These individuals, along with laboratory-hatched phyllosoma, allowed us to describe the morphology of this larval stage. Panulirus pascuensis stage I phyllosoma were observed in fall, suggesting that larval development would be synchronized with the productivity cycle in the region of Rapa Nui, where maximum chlorophyll concentration is observed during austral winter.