ABSTRACT
The Leptasterias hexactis (Echinodermata: Asteroidea) species complex is an important group of intertidal predators, but these six-rayed sea stars have a complex genetic structure and uncertain taxonomic status. We studied 640 sea stars from 18 intertidal locations between Port Renfrew, British Columbia and San Simeon, California. The sea stars were identified using morphological and genetic criteria to four nominal species: Leptasterias epichlora (Brandt, 1835), L. hexactis (Stimpson, 1862), L. aequalis (Stimpson, 1862) and L. pusilla Fisher, 1930. A maximum of two species was found at any intertidal location; hybridization occurred at three locales where species were sympatric (10/640 = 1.6% of the sea stars were hybrids). Morphological analyses agreed with allozyme results for all locales north of Pigeon Point, CA; however, south of there at Point Pinos, specimens from the rocks were morphologically intermediate between L. aequalis and L. hexactis and were classified as L. hexactis based on allozyme analysis. L. aequalis (171 individuals at 6 locations) were found under rocks at Port Renfrew, BC and Sekiu, Washington but at locations on the outer coast of the continental United States they were attached to rocks, on the walls of a sea cave or in mussel beds as far south as Patricks Point, CA. L. hexactis (428 individuals) were found under rocks or in high intertidal pools which do not drain at low tide at 14 locations ranging from Sekiu, WA to San Simeon, CA. Leptasterias epichlora were found at 5 locations (31 sea-stars) but only incidentally (6 individuals) south of Sekiu, WA. Leptasterias aequalis and L. hexactis exhibit habitat and substrate affinities north of Pigeon Point, CA. There is evidence from allozyme data of a second species (probably L. pusilla Fisher 1930) in the tidepools at Point Pinos, CA and (less clearly) at Pigeon Point and San Simeon, CA.
