Morphological Variations Among Larval-Postlarval Intermediates Produced by Eyestalk Ablation in the Snapping Shrimp Alpheus heterochaelis Say

The eyestalk of many crustaceans contains the X-organ, the presumptive site of production and release of many protein and peptide hormones into the hemolymph. Removal of the eyestalk deprives the animal of these hormones and is known to affect many physiological processes in the adult and developing larva. In the snapping shrimp Alpheus heterochaelis Say, eyestalk ablation performed early in larval development has profound effects on morphogenesis, causing the appearance of supernumerary larval stages, accompanied by retardation and even complete arrest of morphogenesis. In this study, we examined the effects on morphogenesis of bilateral eyestalk removal at carefully controlled intervals. We found that the crucial point for this operation—the point at which the animal attains the ability to metamorphose fully—is just before the onset of ecdysis to the third instar. Additionally, the pattern of development and morphogenesis among body segments follows a discernible double gradient pattern along the anterior-posterior axis in which the extremities of the animal attain the potential for morphogenetic advance prior to the central thorax. This pattern of morphogenesis, punctuated by ecdysis, is a continuous rather than a stepwise or compartmentalized phenomenon.

[1]  J. Freeman,et al.  Endocrine control of spine epidermis resorption during metamorphosis in crab larvae , 1983, Wilhelm Roux's archives of developmental biology.

[2]  M. Prescott,et al.  Identification of methyl farnesoate in the cypris larva of the barnacle, Balanus amphitrite, and its role as a juvenile hormone. , 2000, Insect biochemistry and molecular biology.

[3]  R. E. Knowlton,et al.  VARIATION IN LARVAL SIZE AFTER EYESTALK ABLATION IN LARVAE OF THE SNAPPING SHRIMP ALPHEUS HETEROCHAELIS , 1999 .

[4]  P. Takáč,et al.  Effect of Methyl Farnesoate on Late Larval Development and Metamorphosis in the Prawn Macrobrachium rosenbergii (Decapoda, Palaemonidae): A Juvenoid-like Effect? , 1998, The Biological bulletin.

[5]  G. Charmantier,et al.  Endocrine and neuroendocrine regulations in embryos and larvae of crustaceans , 1998 .

[6]  R. E. Knowlton,et al.  Effects of timed eyestalk ablation on molting in larvae of the snapping shrimp, Alpheus heterochaelis Say , 1997 .

[7]  T. K. Hayes,et al.  A neurohormone regulating both methyl farnesoate synthesis and glucose metabolism in a crustacean. , 1997, Biochemical and biophysical research communications.

[8]  J. Chung,et al.  Structure and Significance of Mandibular Organ-inhibiting Hormone in the Crab, Cancer pagurus , 1996, The Journal of Biological Chemistry.

[9]  Lei Liu,et al.  Isolation and characterization of sinus gland neuropeptides with both mandibular organ inhibiting and hyperglycemic effects from the spider crab Libinia emarginata , 1996 .

[10]  R. E. Knowlton.  Effects of larval eyestalk extirpation on morphogenesis and molting in the snapping shrimp Alpheus heterochaelis say , 1994 .

[11]  G. Charmantier,et al.  INTERMEDIATE LARVAL AND POSTLARVAL STAGES OF HOMARUS AMERICANUS H. MILNE EDWARDS, 1837 (CRUSTACEA: DECAPODA) , 1987 .

[12]  M. Fingerman.  THE ENDOCRINE MECHANISMS OF CRUSTACEANS , 1987 .

[13]  E. S. Chang,et al.  Methyl farnesoate and its role in crustacean reproduction and development , 1987 .

[14]  L. H. Kleinholz.  Crustacean Neurosecretory Hormones and Physiological Specificity , 1976 .

[15]  R. E. Knowlton.  Larval development of the snapping shrimp Alpheus heterochaelis Say, reared in the laboratory , 1973 .

[16]  J. Costlow.  The effect of eyestalk extirpation on larval development of the mud crab, Rhithropanopeus harrisii (Gould)☆ , 1966 .

[17]  L. Passano.  THE REGULATION OF CRUSTACEAN METAMORPHOSIS , 1961 .

[18]  L. Passano.  CHAPTER 15 – MOLTING AND ITS CONTROL , 1960 .

[19]  D. B. Carlisle,et al.  Endocrine Control in Crustaceans , 1959 .

[20]  F. Fraser.  On the development and distribution of the young stages of Krill (Euphausia superba) , 1936 .

[21]  R. Gurney.  Larvae of decapod crustacea , 1936 .