Morphometry, Reproduction, Diet, and Epizoites of Ovalipes Stephensoni Williams, 1976 (Decapoda, Brachyura)

Abstract

collected by demersal trawl on the continental shelf of the eastern United States from 13- 198 m, between 28? and 37?N, and on 26 specimens from the National Museum of Natural History collections in Washington, D.C. All seven morphometric relationships observed Portunidae) are described. The results are based on observations of 347 specimens were inferred from two changes in allometry of the male chelar propodal length and female abdominal width. Allometric maturity was correlated with gonad, pleopod, and gonopore (carapace length, body depth, propodal length, width and depth of crushing chela, and ab- dominal width) exhibited allometric growth to some extent. Sexual dimorphism was dem- onstrated for chelar propodal length and abdominal width. Prepubertal and pubertal molts development. Males reach full maturity at a carapace width of 61 mm; females complete maturation by the time they reach 51 mm in width. Ovalipes stephensoni is heterochelic and heterodontic with the crushing claw occurring on the right side in 91.6% of the specimens observed. There is little evidence that cheliped laterality changes with age (size). Although this species is an opportunistic carnivore, bivalve mollusks, cephalopods, and small crus- taceans comprised the bulk of the diet. Relatively heavy infestations of lepadid barnacles, Octolasmis muelleri, were found in the branchial chamber. Lesions of the ciliated protozoan were present in the gill lamellae