Thatje, S.; Calcagno, J. A.; Lovrich, G. A.; Sartoris, F. J.; Anger, K.
Temporal pattern of hatching was studied in the subantarctic lithodid crabs Lithodes santolla (Molina) and Paralomis granulosa (Jaquinot) from the Argentine Beagle Channel. In both species, larval hatching occurred in low daily numbers over an extended period of up to several weeks, depending on hatch size. Low daily hatching activity and low oxygen-consumption rates in freshly hatched P. granulosa larvae are discussed as life history adaptations to, and/or physiological constraints by, the environmental conditions of high latitudes.
Gustavo A. Lovrich
Full Text Available Lithodidae is the only group of reptant decapods that occurs in Antarctic waters and has been particularly abundant in the Beagle Channel, Straits of Magellan and south to 50º S. Because of their abundance in coastal waters, the sympatric Lithodes santolla and Paralomis granulosa have constituted a mixed fishery since the 1930s. The two species differ markedly in their reproductive potential. Lithodes santolla is large (maximum size of 190 mm carapace length, CL, and 8 kg weight, has a generation time of 6 yrs., the reproductive cycle is annual and females carry between 5,000-60,000 eggs per female per clutch. In their life span, L. santolla females produce 6 times more eggs than P. granulosa females. Paralomis granulosa is smaller than its relative (maximum 115 mm CL and 1.5 kg weight, and has a slower growth rate, resulting in a generation time of 12 yrs. The reproductive cycle is biennial and females carry between 800-10,000 eggs per female per clutch. Moreover, the reproductive potential of P. granulosa is reduced because an important proportion of the largest and more prolific females of the population do not carry eggs. In other terms, in one generation time of P. granulosa, two complete generations of L. santolla are produced, and compared to other Subantarctic lithodids L. santolla is the most prolific species. The higher reproductive potential of L. santolla probably confers to this species the ability to recover more rapidly from an overfishing situation.
Schvezov, N; Lovrich, G A; Florentín, O; Romero, M C
Environmental and physiological variations influence the steady-state concentration of free oxygen radicals in cells. Because of the seasonal life cycle of Lithodes santolla in the Beagle Channel, a baseline study of the antioxidant physiological variations along the seasons is necessary for a better understanding of its ecophysiology. The aim of this study was to evaluate the seasonal variations in gills, hemolymph, muscle and hepatopancreas of the: i) enzymatic activities of superoxide dismutase, catalase, glutathione peroxidase and glutathione transferase; ii) ascorbic acid and total glutathione; iii) lipid peroxidation and protein oxidation; iv) glucose, proteins and pH. Seasonality found in the antioxidant defense system of L. santolla from the Beagle Channel acts in a collaborative way during the most relevant life cycle phases (reproduction and molting), avoiding a long term oxidative stress. The antioxidant system also shows changes in the enzymatic activities likely caused by the environmental factors, such as low temperatures during winter and spring seasons. Copyright © 2014 Elsevier Inc. All rights reserved.
Oscar Antonio Amin
Full Text Available Effects of copper toxicity on zoea I of Lithodes santolla (Decapoda: Anomura were analysed. The 96-h LC50 was estimated, resulting in 298.5 µg L-1. Groups of larvae were exposed to sublethal concentrations (40, 80 and 160 µg L-1 for 96 h. Oxygen consumption, ammonia excretion, O:N atomic ratio, lipid peroxidation (LPO and body water content were measured. Oxygen consumption of treated groups (mean 46.92 ± 8.03 µg-atom O2 h-1 mg-1 did not differ significantly with control. Ammonia excretion decreased by 60% at higher Cu concentration (1.61 ± 0.65 µg-atom N-NH3 h-1 mg-1, leading to a 117% increase in the O:N ratio. LPO values during the exposure time were higher in all treatments than in the controls. The water content was significantly higher in treatments than in controls. The highest concentration assayed, which represents about 50% of 96-h LC50, had evident effects on the parameters analysed. The values of copper in water reported for the coastal zone of Ushuaia bay exceed the value established by the United States Environmental Protection Agency (USEPA for ambient water quality criteria. Therefore, the results obtained in the present study are a contribution to the study of potential effects of copper as a common stressor in the first larval stage of this commercial species of the Beagle Channel.
National Oceanic and Atmospheric Administration, Department of Commerce — The data from this study, describes embryo development in Golden king crab, Lithodes aequispinus. Six female multiparous golden king crab were captured from the...
Uriarte, Iker; Hernández, Jorge; Dörner, Jessica; Paschke, Kurt; Farías, Ana; Crovetto, Enzo; Rosas, Carlos
Globally, octopus larviculture is one of the challenges faced in the attempt to diversify aquaculture and achieve cephalopod farming. Currently, only juveniles of Octopus vulgaris, Octopus joubini, and Enteroctopus dofleini have been obtained at an experimental level. This is the first study to look at the characteristics of planktonic and benthic Robsonella fontaniana juveniles in an effort to analyze the morphometric changes occurring during their planktonic and benthic phases and to explore the feasibility of obtaining settlement under controlled conditions. The morphometric measurements varied exponentially over time and did not show different tendencies before and after settlement. Mantle growth in relation to total length fit a logarithmic regression, whereas arm length and eye diameter increased linearly with respect to total length throughout the entire paralarval and juvenile periods. This suggests that the size of the mantle decreases with age in proportion to the total octopus length, whereas the organs more directly involved in catching prey tend to increase in direct proportion to the total length. The present study shows that R. fontaniana can be reared from hatching through the final paralarval stage on a diet of Lithodes santolla (king crab) zoeae; after settlement, the juveniles can be reared on a diet of crab such as Petrolisthes.
Gustavo A. Lovrich
Full Text Available This is the first study in the Beagle Channel that reports the larval seasonal distribution, abundance and duration of the larval stages of Anomura and Brachyura, on the basis of a fortnightly sampling programme. An identification key to the specific level of zoeal stages is included. Between September 1987 and March 1989, 304 plankton samples were taken by means of oblique hauls from the bottom to the sea-surface. Eighty-five percent of the samples were taken shallower than 60 m depth. Decapod larvae occurred only in spring and summer. All but two taxa showed a single cohort of larvae which emerge at the beginning of the spring. A second cohort of Munida spp. and Halicarcinus planatus also occurred during summer. The most abundant taxa were Munida spp. (312 larvae ? 10 m-3, Peltarion spinosulum (288 larvae ? 10 m-3,, H. planatus (143 larvae ? 10 m-3, and Pagurus spp. (79 larvae ? 10 m-3, which represented 97% of the total larvae collected. Larvae of Pinnotheridae, Eurypodius latreillii, Libidoclaea granaria, and Paralomis granulosa were about an order of magnitude less abundant. Relative abundances of larvae correspond to relative abundances of the respective benthic stages. The absence of certain larval stages or of certain species (Acanthocyclus albatrossis and Lithodes santolla probably indicates their differential distribution within the Beagle Channel. Particularly, lithodid larvae may have benthic or epibenthic habits.
Wolf E. Arntz
Full Text Available This paper comprises the decapod crustacean material collected during the Victor Hensen campaign 1994 and during the last phase of Polarstern cruise ANT XIII/4 in 1996. Sampling covered waters of medium and greater depth in the Straits of Magellan, the channels towards the south, and the area south of the Beagle Channel including the northern slope of the Drake Passage. 30 species of decapods were found, which is considered a good result taking into account that the species restricted to the intertidal and the upper subtidal, which were not subject of this study, are missing. Anomurans were the dominant group, followed by brachyurans and caridean shrimps. Additionally one palinuran (Stereomastis suhmi; n=8 and a single specimen of the astacuran Thymops birsteini were found. Dominance patterns changed considerably from the Straits of Magellan to the channel system south of the Strait, and again to the area south of the Beagle and the northern slope of the Drake Passage. Among the top dominants were the galatheid Munida spp., which in the southernmost area numerically contributes >90% to the catches, the brachyuran crabs Peltarion spinosulum and Eurypodius latreillii, the hermit crab Pagurus comptus, and the caridean shrimps Austropandalus grayi and Pasiphaea acutifrons. Munida spp. and P. spinosulum also revealed the highest frequency of occurrence at 49% and 45% of the stations, respectively, followed by E. latreillii, P. comptus, and A. grayi. Regional and bathymetric distribution of the principal species are given. The depth range of some species was found to be very wide (Campylonotus semistriatus, Munida spp., E. latreillii, P. spinosulum whereas others were restricted to relatively shallow waters (Pagurus gaudichaudii, Lithodes santolla, Campylonotus vagans, A. grayi or great depth (Nematocarcinus lanceopes, Stereomastis suhmi. It should be mentioned, however, that sampling depths differed greatly in the areas of study. Contrary to the
Julio H. Vinuesa
Full Text Available We report the occurrence of Lithodes turkayi (Anomura, Libidoclaea granaria, and C. edwardsii (Brachyura, in the Beagle Channel. This observation extends their range of distribution south of the previously reported limit of the Straits of Magellan. Acanthocyclus albatrossis (Brachyura occurs south of Isla Navarino and also in the Beagle Channel, however in a particular habitat of its northern coast. The occurrence of Lithodes confundens (formerly identified as L. antarcticus north of the eastern entrance of the Straits of Magellan is also reported. We extend its range of distribution northerly and its bathymetric distribution to the intertidal.