Morphology of mandibles and food size in two fairy shrimps (Branchiopoda: Anostraca) from Thailand

In a recent study, we quantified the scaling of ingested food size (Vb )—the maximum size at which an animal consistently ingests food whole—and found that Vb scaled isometrically between species of captive strepsirrhines. The current study examines the relationship between Vb and body size within species with a focus on the frugivorous Varecia rubra and the folivorous Propithecus coquereli. We found no overlap in Vb between the species (all V. rubra ingested larger pieces of food relative to those eaten by P. coquereli), and least-squares regression of Vb and three different measures of body mass showed no scaling relationship within each species. We believe that this lack of relationship results from the relatively narrow intraspecific body size variation and seemingly patternless individual variation in Vb within species and take this study as further evidence that general scaling questions are best examined interspecifically rather than intraspecifically.

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The ecology of the island-lizard Podarcis sicula salfii

Amphibia-Reptilia ◽

10.1163/156853881x00078 ◽

1981 ◽

Vol 2 (3) ◽

pp. 243-257 ◽

Cited By ~ 20

Author(s):

P.E. Ouboter

Keyword(s):

Body Temperature ◽

Interspecific Competition ◽

The Sun ◽

Podarcis Sicula ◽

Dense Vegetation ◽

Food Size ◽

Preferred Body Temperature ◽

Erica Arborea ◽

Sufficient Food ◽

Excursion Time

AbstractIn the summers of 1974 till 1979 microdistribution of Podarcis sicula saffti was examined. Areas without much vegetation and areas with dense vegetation have low densities. Horizontal space, predators, parasites, interspecific competition, shelter and dew appear to be non important factors in the microdistribution of P. s. safii. From 9 a. m. until 6 p. m. temperature in the sun is above PBT (preferred-body-temperature) in all zones. Shade temperature is different from one zone to another. In the most rocky zone without much vegetation, shade is provided by crevices. Shade temperature is under PBT. Food is mainly available outside crevices, in vegetation of Statice sinuatum. Food-size is small, so excursion-time will be long. Lizards are able to collect sufficient food if Statice-plants are close to crevices. The zone with vegetation of Erica arborea, on top of the island, is shaded all day. Shade temperature is under PBT. Only clearings are inhabited by lizards. All other zones have bushes and open areas. During the hot hours bushes provide shade, with shade temperature close to PBT. Food is mainly available in these bushes.

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Feeding patterns in Eubranchipus grubii (Dybowski 1860) (Branchiopoda: Anostraca) and its potential influence on the phytoplankton communities of vernal pools

Journal of Limnology ◽

10.4081/jlimnol.2018.1705 ◽

2018 ◽

Vol 77 (2) ◽

Author(s):

Sofia Celewicz ◽

Michał Jan Czyż ◽

Bartłomiej Gołdyn

Keyword(s):

Cell Volume ◽

Phytoplankton Community ◽

Grazing Pressure ◽

Potential Influence ◽

Filter Feeder ◽

Algal Communities ◽

Phytoplankton Communities ◽

Fairy Shrimps ◽

The Mean ◽

And Control

Filtration patterns in the fairy shrimp Eubranchipus grubii were analysed under laboratory conditions using water containing phytoplankton from their actual locality in western Poland. After 48 hours of feeding, we compared the structure of algal communities in water samples in treatments with males, females and control. The mean filtration rate for E. grubii was relatively high (14,488 mL h-1) in comparison to other crustacean filter feeders and was higher for females than for males. Fairy shrimps grazed effectively on all 11 dominant phytoplankton taxa and there was no sign of overall preferences with regard to taxon, cell volume, length or shape. Female fairy shrimps removed significantly more cells of three taxa (Cryptomonas erosa, C. ovata and Trachelomonas volvocina). The differences between sexes did not depend on the cell volume or length of particular phytoplankton taxa but were significantly related to their initial abundance, initial biomass and shape. The higher the abundance and biomass of the algal taxa, the more intensively it was grazed by females than by males. Females were also observed to graze more on spherical and elongated cells. In conclusion, our results show E. grubii to be an effective, generalist filter feeder capable of significantly influencing the phytoplankton community of a vernal pool. Possible implications of such grazing pressure are also discussed.

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