Topic
Gammarus setosus
About: Gammarus setosus is a research topic. Over the lifetime, 20 publications have been published within this topic receiving 296 citations.
Papers
TL;DR: The large size at maturity, continued growth, and long life with resulting high fecundity partially compensate for the production of but one brood per year.
Abstract: Gammarus setosus is a circumpolar species found as far south as the Bay of Fundy region in the northwest Atlantic. Under laboratory conditions (3 °C) sexual maturity is reached in the 13th molt, at 14 mm in the males and at 12 mm in the females. In the field 50%, maturity is attained at 13.5 mm in the females. Mature females annually produce a single autumn brood, which is released in late winter or early spring. They then enter an obligatory resting period. In the laboratory at 12 °C they can have more than one brood annually. Fecundity increases with the size of the Female. The large size at maturity, continued growth, and long life with resulting high fecundity partially compensate for the production of but one brood per year.
54 citations
TL;DR: The distribution of Gammarus oceanicus, G. setosus and G. wilkitzkii was studied over the period 1981–1991 in the coastal zone of the Svalbard and Franz Josef Land archipelagos, finding that G. oceanicus is connected with the presence of Atlantic waters and favourable ice conditions.
Abstract: The distribution of Gammarus oceanicus, G. setosus and G. wilkitzkii was studied over the period 1981–1991 in the coastal zone of the Svalbard and Franz Josef Land archipelagos. The occurrence of G. oceanicus is connected with the presence of Atlantic waters and favourable ice conditions. In the area investigated this species was found on the west and north coasts of the island Vestspitsbergen only. G. setosus occurs in most of the investigated localities, being most abundant in the inner fjord basins and other sheltered waters. G. wilkitzkii occurs typically in ice-associated plankton, but occurs in the intertidal zone among; algae at Franz Josef Land. The maximum densities of gammarids attained 2000 ind/m2 at maximum, the mean being about 300 ind/m2 , the typical site being large stones in sheltered bays at low water.
31 citations
TL;DR: It is concluded that these two Gammarus species have their own endogenous rhythms and that the role of photoperiod is to time the reproductive cycle.
Abstract: SYNOPSIS. Gammarus species time the release of their young by using ovarian diapause and the duration of embryonic development. During diapause vitellogenesis is arrested and oostegite setae are lost. The onset of diapause is influenced by photoperiod under experimental conditions. Two Gammarus species were studied. Gammarus lawrencianus is typical of the majority of Gammarus species that produce sequential broods through the summer and have a diapause in the autumn. Gammarus setosus is typical of those which have an obligatory diapause lasting most of the year that follows the annual autumn brood. Experimental short day photoperiods (4L to 12L) induce vitellogenesis in Gammarus setosus , and have the opposite effect on Gammarus lawrencianus . Long day photoperiods promote vitellogenesis in Gammarus lawrencianus and prolong the duration of diapause in Gammarus setosus . It is concluded that these two Gammarus species have their own endogenous rhythms and that the role of photoperiod is to time the reproductive cycle. Short days near the time of the fall equinox ensure that this timing is synchronized over a range of latitudes. The effect of photoperiod is modulated by the influence of temperature on embryonic development over the broad range of geographic latitude inhabited by the species. Short photoperiods inhibit but do not prevent sexual maturation of the young. Short days also result in a slower average growth rate and greater size at maturity.
29 citations
TL;DR: It is suggested that the genus Gammarus sensu lato has originated in warm water in the Tethys Sea region, and that the species found in the northwestern Atlantic have radiated from there.
Abstract: The geographic distribution of the northern Gammarus species of the northwestern Atlantic, arranged from north to south, is as follows: circumpolar, Gammarus wilkitzkii and Gammarus setosus; both shores of the Atlantic, Gammarus duebeni, Gammarus finmarchicus, Gammarus obtusatus, Gammarus oceanicus, and Gammarus stoerensis; western Atlantic, Gammarus lawrencianus, Gammarus mucronatus, and Gammarus tigrinus.It is suggested that the genus Gammarus sensu lato has originated in warm water in the Tethys Sea region, and that the species found in the northwestern Atlantic have radiated from there.
22 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2020 | 1 |
| 2019 | 1 |
| 2016 | 1 |
| 2011 | 1 |
| 2002 | 1 |
| 1994 | 2 |