Marked morphological differences between the sexes only occur in those groups where the male transfers sperm directly to the female (ticks and certain mite families). In these cases, the male is usually smaller and may have a differently shaped body to the female, a different complement of sclerotized shields, a pair of suckers flanking the anus, modified cheliceral digits, differently shaped legs, and suckers and/or spurs on certain legs. More than one morphological form of the male occurs in some Astigmata and in the Cheyletidae (Prostigmata). Up to four have been identified in astigmatids. Compared to the female, the homeomorph has the same shaped legs III and body setae lengths. The bimorph has a longer body and longer body setae. The heteromorph has thicker legs III that end in one or two stout claw-like structures (Figure), but similar body setae lengths. The pleomorph has a pair of thickened legs, a longer body and longer body setae. In cheyletids, heteromorphic males differ most obviously in the comparatively larger size of the gnathosoma and its heavier sclerotization and sculpturing.