Ron,
Hemisquilla has a long history of names. Originally the genus was Pseudosquilla, but that was changed to Hemisquilla many years ago. The type specimen was from Chile and was called "ensigera". People started using that for the California animals as well, but there are some references to stylifera. About 20 years ago, it was recognized that there were probably four Hemisquilla. H. braziliensis was given species status and Hemisquilla ensigera was split into three subspecies - californiensis, ensigera, and australiensis. In 2001, Shane Ahyong split them into good species, so the animals from Southern California and Mexico down to Panama are now Hemisquilla californiensis. Those from South America are H. ensigera.
From my looking at the specimens, this is clearly a correct call. They differ on several counts.
Roy