Skip to main content
Journal cover image

Seasonal variability in morphology of blue crab, callinectes sapidus, megalopae and early juvenile stage crabs, and distinguishing characteristics among co-occurring portunidae

Publication ,  Journal Article
Ogburn, MB; Stuck, KC; Heard, RW; Wang, SY; Forward, RB
Published in: Journal of Crustacean Biology
February 1, 2011

Declines in abundance of the commercially important blue crab Callinectes sapidus have led fishery managers to search for new management strategies. Assessing year-class strength at megalopal or early juvenile stages may contribute to this effort, but separation from co-occurring species is difficult in many areas because morphological characteristics vary with season and published descriptions do not adequately distinguish C. sapidus from C. similis and other related species. Callinectes sapidus and C. similis megalopae were collected monthly and cultured in the laboratory to a size at which positive identification could be made. Measurements on intact megalopae and early crab exuviae of both species revealed seasonal differences, with spring megalopae having larger carapaces, longer rostral spines and antennae and more setae on some mouth parts than fall megalopae. This seasonal pattern of morphological variability was verified through examination of samples collected from MS (1976-1979) and NC (2005) coastal waters. Rostrum length, total carapace length and rostrum length as a percent of total carapace length of NC megalopae were negatively correlated with water temperature 2-4 weeks prior to collection. Callinectes sapidus and C. similis megalopae can be rapidly separated within locations and seasons by: 1) the shape of the antero-lateral carapace margin, 2) rostral length as a percent of total carapace length, and 3) the combined length of the distal eight segments of the antenna. Such rapid separation is essential for fisheries studies requiring identification of large numbers of individuals. Molecular analyses or more detailed morphological analyses remain necessary for definitive separation regardless of season. Keys to common coastal portunid megalopae and first crab stages were compiled to aid investigators in separating C. sapidus megalopae and early juvenile stages from co-occurring portunids. © The Crustacean Society.

Duke Scholars

Published In

Journal of Crustacean Biology

DOI

ISSN

0278-0372

Publication Date

February 1, 2011

Volume

31

Issue

1

Start / End Page

106 / 113

Related Subject Headings

  • Marine Biology & Hydrobiology
  • 3109 Zoology
  • 3103 Ecology
  • 0608 Zoology
  • 0603 Evolutionary Biology
  • 0602 Ecology
 

Citation

APA
Chicago
ICMJE
MLA
NLM
Ogburn, M. B., Stuck, K. C., Heard, R. W., Wang, S. Y., & Forward, R. B. (2011). Seasonal variability in morphology of blue crab, callinectes sapidus, megalopae and early juvenile stage crabs, and distinguishing characteristics among co-occurring portunidae. Journal of Crustacean Biology, 31(1), 106–113. https://doi.org/10.1651/09-3241.1
Ogburn, M. B., K. C. Stuck, R. W. Heard, S. Y. Wang, and R. B. Forward. “Seasonal variability in morphology of blue crab, callinectes sapidus, megalopae and early juvenile stage crabs, and distinguishing characteristics among co-occurring portunidae.” Journal of Crustacean Biology 31, no. 1 (February 1, 2011): 106–13. https://doi.org/10.1651/09-3241.1.
Ogburn, M. B., et al. “Seasonal variability in morphology of blue crab, callinectes sapidus, megalopae and early juvenile stage crabs, and distinguishing characteristics among co-occurring portunidae.” Journal of Crustacean Biology, vol. 31, no. 1, Feb. 2011, pp. 106–13. Scopus, doi:10.1651/09-3241.1.
Journal cover image

Published In

Journal of Crustacean Biology

DOI

ISSN

0278-0372

Publication Date

February 1, 2011

Volume

31

Issue

1

Start / End Page

106 / 113

Related Subject Headings

  • Marine Biology & Hydrobiology
  • 3109 Zoology
  • 3103 Ecology
  • 0608 Zoology
  • 0603 Evolutionary Biology
  • 0602 Ecology