Embryonic development of the South American long-fin squid Loligo sanpaulensis Brakoniecki, 1984

BARÓN, PEDRO J.

JOURNAL OF MOLLUSCAN STUDIES

Oxford University Press

Año: 2003 vol. 25 p. 1347 - 1358

0260-1230

The embryology of Loligo sanpaulensis, a south-western Atlantic squid, was studied for the first time. Egg masses were obtained by SCUBA divers in Nuevo Gulf, Argentina, and embryos were incubated in aquaria at five temperatures from 12° to 23°C. A scale of embryonic development was created for the species and the chronology of organ formation was compared with that of other loliginids. Embryogenesis was completed in incubations at 16.2° and 19°C. At 23°, 12.5° and 12°C, all embryos died after hatching. At 19°C, development from blastulation to hatching lasted 14 days (276° d daily accumulated temperature, DAT). A total of 310° d DAT was estimated for complete embryonic development of the species. Stages of blastulation and organogenesis showed few differences relative to those described for Loligo pealei (in Arnold, 1965). In the study area, near the southern limit of the distribution of the species, seawater temperatures under 13°C are expected to restrict the embryonic development to the warmest months of the year (November–May). Arnold, 1965). In the study area, near the southern limit of the distribution of the species, seawater temperatures under 13°C are expected to restrict the embryonic development to the warmest months of the year (November–May). masses were obtained by SCUBA divers in Nuevo Gulf, Argentina, and embryos were incubated in aquaria at five temperatures from 12° to 23°C. A scale of embryonic development was created for the species and the chronology of organ formation was compared with that of other loliginids. Embryogenesis was completed in incubations at 16.2° and 19°C. At 23°, 12.5° and 12°C, all embryos died after hatching. At 19°C, development from blastulation to hatching lasted 14 days (276° d daily accumulated temperature, DAT). A total of 310° d DAT was estimated for complete embryonic development of the species. Stages of blastulation and organogenesis showed few differences relative to those described for Loligo pealei (in Arnold, 1965). In the study area, near the southern limit of the distribution of the species, seawater temperatures under 13°C are expected to restrict the embryonic development to the warmest months of the year (November–May). Arnold, 1965). In the study area, near the southern limit of the distribution of the species, seawater temperatures under 13°C are expected to restrict the embryonic development to the warmest months of the year (November–May). Loligo sanpaulensis, a south-western Atlantic squid, was studied for the first time. Egg masses were obtained by SCUBA divers in Nuevo Gulf, Argentina, and embryos were incubated in aquaria at five temperatures from 12° to 23°C. A scale of embryonic development was created for the species and the chronology of organ formation was compared with that of other loliginids. Embryogenesis was completed in incubations at 16.2° and 19°C. At 23°, 12.5° and 12°C, all embryos died after hatching. At 19°C, development from blastulation to hatching lasted 14 days (276° d daily accumulated temperature, DAT). A total of 310° d DAT was estimated for complete embryonic development of the species. Stages of blastulation and organogenesis showed few differences relative to those described for Loligo pealei (in Arnold, 1965). In the study area, near the southern limit of the distribution of the species, seawater temperatures under 13°C are expected to restrict the embryonic development to the warmest months of the year (November–May). Arnold, 1965). In the study area, near the southern limit of the distribution of the species, seawater temperatures under 13°C are expected to restrict the embryonic development to the warmest months of the year (November–May). Loligo pealei (in Arnold, 1965). In the study area, near the southern limit of the distribution of the species, seawater temperatures under 13°C are expected to restrict the embryonic development to the warmest months of the year (November–May).