Cyrtograpsus angulatus Brachyura: Grapsidae
نویسندگان
چکیده
The grapsid crabs Chasmagnathus granulata and Cyrtograpsus angulatus are considered as key species within the benthic communities of estuaries and brackish coastal lagoons in the southwestern Atlantic region. In controlled laboratory experiments, we studied the intensity of interspecific predation as well as intraand intercohort cannibalism in setllers in relation to refuge Ž . availability, predator characteristics species, size, sex, nutritional state , and the presence or Ž . absence of an alternative food source Artemia nauplii . In both species, the intensity of Ž . intracohort cannibalism among recently settled crabs instars I and II, AsettlersB was low, with ca. 5% mortality during 48 h experimental observation periods. Larger juveniles and adults of both species, by contrast, preyed heavily on the settlers. Predation was significantly reduced when refuges were available for the settlers. Hunger of the predators enhanced in general the predation rate. In the presence of alternative food, the consumption of settlers was significantly reduced. In C. granulata, adult females ate more settlers than the males, probably as a consequence of differences in the morphometric traits of their chelae. Cannibalism and predation by juvenile and adult crabs may play an important role in the regulation of recruitment success for both species and hence, in the structure of estuarine benthic communities. q 2001 Elsevier Science B.V. All rights reserved.
منابع مشابه
Patterns and Processes of Chasmagnathus granulata and Cyrtograpsus angulatus (Brachyura: Grapsidae) Recruitment in Mar Chiquita Coastal Lagoon, Argentina
Recruitment patterns of crabs and other benthic invertebrates with planktonic larvae are determined by a combination of preand post-settlement factors. Recruitment is considered settlement limited when there is a positive correlation between the postlarvae available in the water column and the number of recruits, and regulated when abundance of individuals is mainly affected by post-settlement ...
متن کاملThe Taxonomy of Sesarma tangi Rathbun, 1931 and S. stormi De Man, 1895 (Crustacea: Decapoda: Brachyura: Grapsidae: Sesarminae), with Establishment of a New Genus for S. stormi
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A molecular method for the detection of sally lightfoot crab larvae (Grapsus grapsus, Brachyura, Grapsidae) in plankton samples
The decapod Grapsus grapsus is commonly found on oceanic islands of the Pacific and Atlantic coasts of the Americas. In this study, a simple, quick and reliable method for detecting its larvae in plankton samples is described, which makes it ideal for large-scale studies of larval dispersal patterns in the species.
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This study evaluated the effect of the burrowing crab Chasmagnathus granulata on the benthic community in mudflats of the Mar Chiquita coastal lagoon (Argentina, 378 459 S, 578 269 W). A significantly higher abundance of the polychaete Laeonereis acuta was found inside the C. granulata crab bed than outside. However, L. acuta abundance decreased in summer probably due to the greater activity of...
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A Jiew freshwater crab, h'csonna dotpin'tmm sp. ji.h is described from Jamaica. The number of known Jamaican e-jidteinic Sesairriinfle increases thereby tu> eigln. Half of the American species of .Vmnwfl feriown fit present are mct&mic in Jamaica. The new species in locally restricted to the slopes of toe Dolphin Head Mountain in western Jamaica. It jwobahiy evolved when sea-level fllJCHJiiiiou...
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