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Fairy Shrimp (fairy + shrimp)
Selected AbstractsA New Species of Streptocephalus Fairy Shrimp (Crustacea, Anostraca) with Tetrahedral Cysts from Central ThailandINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 3 2006La-Orsri Sanoamuang Abstract A new species of fairy shrimp, Streptocephalus siamensis n. sp., is described from five temporary pools in Suphan Buri and Kanchana Buri Provinces, central Thailand. It sometimes co-occurs with its congener, S. sirindhornae . This new species belongs to the subgenus Parastreptocephalus which is defined by bearing tetrahedral cysts. This is the third anostracan species reported from Thailand. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Structure and Functioning of the "Egg Bank" of a Fairy Shrimp in a Temporary Pool: Chirocephalus ruffoi from Pollino National Park (Southern Italy) as a Case StudyINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 1 2004Graziella Mura Abstract To investigate their distribution and total numbers, resting eggs of the anostracan Chirocephalus ruffoi were collected from the bed of a temporary pool in southern Italy. Samples were taken at 0.5 m intervals along six transects oriented at 30° from each other, by means of a cylindrical core sampler. The horizontal distribution of intact resting eggs was extremely patchy, with cyst number per core ranging from 191 to 1,400 (CV = 32.7%), corresponding to a mean of between 0.8 and 4.3 cysts cm,3. Differences observed were related to core position and transect orientation, total cyst numbers being markedly higher in the leeward area of the pool compared to the windward area. Marked variation was also evident in vertical distribution, a significant, though weak correlation was recorded between egg density and sediment depth. Cyst-bank size (± 95% confidence limits) of the pool bed, estimated from the mean cyst number cm,3 obtained for the 6 transects, ranged between 1.0 × 108 and 1.3 × 108 cysts. Hatching in the laboratory was very erratic. Despite significant differences in hatching, the observed variation was unrelated to most of the variables considered (position within sections, cores and transects, pre-incubation treatment) and was explained only by initial sediment conditions (moist/dry). In none of the experimental conditions tested was synchronous hatching obtained. Possible causal factors (mixing of the bottom sediments by cattle, egg age, storage conditions, differential exposure to environmental cues as well as variability in hatching response even at clutch level) are discussed. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Foraging tactics in alternative heterochronic salamander morphs: trophic quality of ponds matters more than water permanencyFRESHWATER BIOLOGY, Issue 9 2007MATHIEU DENOEL Summary 1. In lentic freshwater habitats, the composition of animal assemblages shifts along a gradient from temporary to permanent basins. When habitats with different degrees of permanence are at the scale of the home range of species, they constitute alternatives in terms of energy acquisition through feeding. 2. In this context, previous studies showed an advantage of metamorphic over paedomorphic tiger salamanders (Ambystoma tigrinum) in temporary ponds which are only available to metamorphs. The aim of this study was to establish whether salamanders obtain similar benefits in ponds that do not differ in water permanence and whether salamanders shifted from detrimental to advantageous ponds. To this end, we determined the feeding habits, body condition and movement patterns of the two morphs in a complex of four permanent and four temporary ponds. 3. Consistent with previous studies, metamorphs consumed higher-quality diets than paedomorphs in term of energy intake. However, these differences occurred because metamorphs consumed fairy shrimp in a single temporary pond. Individual movement patterns confirmed that most of the metamorphs used different aquatic habitats both within and between years and that most of them moved from permanent ponds for breeding towards the most profitable temporary pond in terms of foraging. 4. These results indicate that habitat selection by salamanders is optimal in term of energy intake in metamorphs that use high quality ponds independently of hydroperiod. It seems that both spatial and temporal variation can influence the relative foraging success of each morph. [source] A New Species of Streptocephalus Fairy Shrimp (Crustacea, Anostraca) with Tetrahedral Cysts from Central ThailandINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 3 2006La-Orsri Sanoamuang Abstract A new species of fairy shrimp, Streptocephalus siamensis n. sp., is described from five temporary pools in Suphan Buri and Kanchana Buri Provinces, central Thailand. It sometimes co-occurs with its congener, S. sirindhornae . This new species belongs to the subgenus Parastreptocephalus which is defined by bearing tetrahedral cysts. This is the third anostracan species reported from Thailand. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] |