INVESTIGADORES
LUPPI tomas Atilio
artículos
Título:
Population structure of the South American estuarine crab, Chasmagnathus granulatus (Brachyura: Varunidae) near the southern limit of its geographical distribution: comparison with northern populations.
Autor/es:
BAS CLAUDIA; LUPPI TOMAS; SPIVAK EDUARDO
Revista:
HYDROBIOLOGIA
Editorial:
Springer
Referencias:
Año: 2005 vol. 537 p. 217 - 228
ISSN:
0018-8158
Resumen:
Abstract
Crabs are among the most conspicuous and ecologically important invertebrates of the large intertidal
zones that characterize estuarine and protected coastal areas in temperate regions. The habitat, population
structure and breeding cycle of Chasmagnathus granulatus (Brachyura: Varunidae), a semiterrestrial burrowing
crab endemic to the warm temperate coasts of the Southwestern Atlantic, were studied in San
Antonio Bay (Argentina), near the southern limit of its range. San Antonio Bay has no freshwater input,
winter is relatively colder, and summer warmer, than northern habitats of this species. Crabs lived both in
vegetated and unvegetated zones, but density and sex ratio varied among dates and zones. The maximum
observed density was 136 crabs/m2, the maximum carapace width (CW) was 32 mm (males) and 29.8 mm
(females), ovigerous females were found only in November and January, and the smallest ovigerous female
measured 17 mm CW. The population structure, spatial distribution, and recruitment pattern of C. granulatusChasmagnathus granulatus (Brachyura: Varunidae), a semiterrestrial burrowing
crab endemic to the warm temperate coasts of the Southwestern Atlantic, were studied in San
Antonio Bay (Argentina), near the southern limit of its range. San Antonio Bay has no freshwater input,
winter is relatively colder, and summer warmer, than northern habitats of this species. Crabs lived both in
vegetated and unvegetated zones, but density and sex ratio varied among dates and zones. The maximum
observed density was 136 crabs/m2, the maximum carapace width (CW) was 32 mm (males) and 29.8 mm
(females), ovigerous females were found only in November and January, and the smallest ovigerous female
measured 17 mm CW. The population structure, spatial distribution, and recruitment pattern of C. granulatus2, the maximum carapace width (CW) was 32 mm (males) and 29.8 mm
(females), ovigerous females were found only in November and January, and the smallest ovigerous female
measured 17 mm CW. The population structure, spatial distribution, and recruitment pattern of C. granulatusC. granulatus
did not differ between San Antonio Bay and northern habitats. The higher density, smaller maximum
size and shorter reproductive cycle observed in San Antonio cannot be atributed to changes associated with
a latitudinal cline and other factors, such as thermal amplitude and food availability, need to be studied.