Extended parental care in two endobenthic amphipods

Abstract
Extended parental care is described for two endobenthic amphipods which inhabit the estuarine soft-bottoms along the Gulf of Maine. The juveniles of both amphipod species, Leptocheirus pinguis and Casco bigelowi, remain in the burrow of their mother after they hatch from the brood pouch. Several consecutive clutches of L. pinguis can inhabit the female's burrow simultaneously, but in C. bigelowi there is always only one clutch of juveniles in the burrow of the female. Larger juveniles of L. pinguis start building their own small tubes at the bottom of the female's burrow. Casco bigelowi females increase the size of their burrows during the time when the juveniles grow. The juveniles of both species leave the female's burrow at about half adult size. The major tasks of female L. pinguis and C. bigelowi during the time of extended parental care is to irrigate and maintain the deep burrow. It is hypothesized that extended parental care in L. pinguis, C. bigelowi and other tube/burrow-living peracarids is a mechanism to protect small offspring from epibenthic predation.