It took a while, but Ryan finally completed the guide to the trematodes infecting the California horn snail. Although these parasites have been subject to a large amount of taxonomic,
biological, evolutionary, and ecological research–and we’ve even proposed to use them as ecological indicator tools–we’ve lacked a satisfactory guide. This should help fill the void for a while. It’s out at Zootaxa: https://www.mapress.com/j/zt/article/view/zootaxa.4711.3.3 .