. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. ONTOGENY OF DECAPOD OSMOREGULATION 105 a slight decrease early in stage I, the 24 h LS50 increased through stages I, II, and III from about 410 mosm-kg~' (14%o) to a maximum (corresponding to a minimum tol- erance) of 500 mosm-kg'1 (17%o) in stages III D and IV A-B preceding and following metamorphosis. In post- larval stages IV and V (in molting stage C), salinity toler- ance reached its maximum, with 24 h LS50 values down to 340 mosm-kg"1 () and 310 mosm-kg"1 (); however, LS50 increased during the mol
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. ONTOGENY OF DECAPOD OSMOREGULATION 105 a slight decrease early in stage I, the 24 h LS50 increased through stages I, II, and III from about 410 mosm-kg~' (14%o) to a maximum (corresponding to a minimum tol- erance) of 500 mosm-kg'1 (17%o) in stages III D and IV A-B preceding and following metamorphosis. In post- larval stages IV and V (in molting stage C), salinity toler- ance reached its maximum, with 24 h LS50 values down to 340 mosm-kg"1 () and 310 mosm-kg"1 (); however, LS50 increased during the molt from stage IV to stage V. The 48-h LS50, although higher by 10-40 mosm-kg'1 (), followed the same pat- tern of variation. Molting between larval stages was pos- sible in respectively 0%, about 50%, and more than 80% of the larvae in media of 700 mosm-kg'1 (, , ). H. americanus: osmoregulatory ability Adaptation time. After a rapid transfer from seawater at 850 mosm-kg'1 (29%o) to a dilute medium of 500 mosm-kg"1 (17%o), the hemolymph osmotic pressure stabilized within 1 h in stages I and II, 2 h in stage III and 3-6 h in stage IV (Fig. 2). Osmotic adaptation to concentrated media of 1100 and 1300 mosm-kg'1 (37 and 44%o) was completed in 1-3 h. In all subsequent ex- periments we kept the animals 6-24 h in each medium before sampling. Osrnoregulation. The types of osmoregulation were 900i- 800 600 500 -. 6 18 20 Time (h) 24 Figure 2. Change in hemolymph osmotic pressure (HL) in stages I-IV of Homarus americanus after rapid transfer from seawater (850 mosm • kg~', 29%o) to a dilute medium (500 mosm • kg"'. 17%o) at 20°C. Each point represents the mean value of determinations from 12-15 animals, with 95% confidence Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original wor
Size: 1490px × 1677px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
