EXOSKELETAL ABRASION AS AN INDICATOR OF REPRODUCTIVE READINESS IN THESPIDER CRAB LIBINIA-EMARGINATA

Patterns of exoskeletal abrasion on the carapace of long-clawed males of the spider crab Libinia emarginata appeared to follow specific sequ ences throughout the year. The degree of abrasion coincided with the e nlargement of the reproductive system and increased levels of methyl f arnesoate in the hemolymph. The patterns of abrasion apparently marked the time elapsed since the last molt, and when the abrasion extended beyond the midcarapace, it appeared to indicate increased reproductive readiness.