Simbiosis entre <i>Collisella</i> spp. (Gastropoda) y <i>Zygantroplana</i> ups (Platyhelminthes: Turbellaria) en el Golfo de California, México

Abstract

The flatworm Zygantroplana ups Marcus & Harry was originally described as a symbiont of the oyster Myrakeena angelica (Rochebrune) from Baja Califomia (BC), Mexico. Here it is recorded in association with several limpet species (Collisella spp.) in Bahía de la Paz, southem BC. The relationship is not species-specific, and there was no association bctween Iimpet body sire and the number of planarians, bu! larger limpets had a greater incidence rateo Si tes with higher limpet densities had lower planarian incidence. Limpet weight was no! affected by the levels of planarian occurrence found here. Ther association may reflect ehance ratner than natural selection.