The present invention relates to a Lactuca sativa seed designated 41-188 RZ, which may exhibit a combination of traits including resistance against downy mildew (Bremia lactucae) races Bl:1 to Bl:31 and Ca-I to Ca-VIII, currant-lettuce aphid (Nasonovia ribisnigri) biotype Nr:0, and to corky root rot (Sphingomonas suberifaciens), as well as having solid main veins and narrow base leaves. The present invention also relates to a Lactuca sativa plant produced by growing the 41-188 RZ seed. The invention further relates to methods for producing the lettuce cultivar, represented by lettuce variety 41-188 RZ.
