Search results for "Triops cancriformis"
showing 6 items of 6 documents
First evidence of underwater sounds emitted by the living fossils Lepidurus lubbocki and Triops cancriformis (Branchiopoda: Notostraca)
2021
Sound is the most effective means of communication in marine and freshwater ecosystems. However, no data about acoustic emissions from non-malacostracan crustaceans are currently available, so their ability to produce sounds is unknown. For the first time, this study investigated the sound produced by 2 tadpole shrimp species,Triops cancriformisandLepidurus lubbocki.L. lubbockiindividuals were collected from a natural temporary pond in Sicily (Italy), whereasT. cancriformisindividuals were obtained from eggs contained in sediment from a rock pool in Sardinia (Italy). In the laboratory, experimental tanks with the animals (one species at a time) were acoustically monitored. Both species prod…
Sex ratio, reproductive mode and genetic diversity inTriops cancriformis
2009
SUMMARY 1. Aquatic invertebrates display a wide array of alternative reproductive modes from apomixis to hermaphroditism and cyclical parthenogenesis. These have important effects on genetic diversity and population structure. Populations of the ‘living fossil’ Triops cancriformis display a range of sex ratios, and various reproductive modes are thought to underlie this variation. Using sex ratio information and histological analyses European populations have been inferred to be gonochoric (with separate males and females), selfing hermaphroditic and androdioecious, a rare reproductive mode in which selfing hermaphrodites coexist with variable proportions of males. In addition, some populat…
Oxygen binding and its allosteric control in hemoglobin of the primitive branchiopod crustacean Triops cancriformis
2007
Branchiopod crustaceans are endowed with extracellular, high-molecular-mass hemoglobins (Hbs), the functional and allosteric properties of which have largely remained obscure. The Hb of the phylogenetically ancient Triops cancriformis (Notostraca) revealed moderate oxygen affinity, cooperativity and pH dependence (Bohr effect) coefficients: P50 = 13.3 mmHg, n50 = 2.3, and ϕ = −0.18, at 20 °C and pH 7.44 in Tris buffer. The in vivo hemolymph pH was 7.52. Bivalent cations increased oxygen affinity, Mg2+ exerting a greater effect than Ca2+. Analysis of cooperative oxygen binding in terms of the nested Monod–Wyman–Changeux (MWC) model revealed an allosteric unit of four oxygen-binding sites and…
Can large branchiopods shape microcrustacean communities in Mediterranean temporary wetlands?
2011
It was recently suggested that large branchiopods may play a keystone role in temporary aquatic habitats. Using a microcosm experiment manipulating microcrustacean communities of Mediterranean temporary wetlands (Camargue, Southern France), we tested the following hypotheses: (i) large branchiopods (the notostracan Triops cancriformis and the anostracan Chirocephalus diaphanus) can limit microcrustacean densities through both competition and predation; (ii) notostracans create high suspended-matter concentrations through bioturbation, which can negatively impact microcrustaceans; and (iii) the outcome of these biotic interactions is more detrimental at high salinities. We found a strong pr…
Sister species within the Triops cancriformis lineage (Crustacea, Notostraca)
2006
301 Korn, M., Marrone, F., Perez-Bote, J. L., Machado, M., Cristo, M., Cancela da Fonseca, L. & Hundsdoerfer, A. K. (2006). Sister species within the Triops cancriformis lineage (Crustacea, Notostraca). — Zoologica Scripta , 35 , 301–322. We investigated the phylogenetic relationships among the three presently recognized subspecies of the tadpole shrimp, Triops cancriformis , using mitochondrial 16S and 12S rDNA sequences. Our results indicate that the taxon is divided into two distinct lineages. One lineage is formed of T. c. cancriformis populations and samples from northern Spain that had been classified as T. c. simplex in the most recent literature. The second lineage comprises all pop…
Native and subunit molecular mass and quarternary structure of the hemoglobin from the primitive branchiopod crustacean Triops cancriformis
2006
Many branchiopod crustaceans are endowed with extracellular, high-molecular-weight hemoglobins whose exact structural characteristics have remained a matter of conjecture. By using a broad spectrum of techniques, we provide precise and coherent information on the hemoglobin of one of the phylogenetically ‘oldest’ extant branchiopods, the tadpole shrimp Triops cancriformis. The hemoglobin dissociated under reducing conditions into two subunits, designated TcHbA and TcHbB, with masses of 35 775 ± 4 and 36 055 ± 4 Da, respectively, determined by ESI-MS. Nonreducing conditions showed only two disulfide-bridged dimers, a homodimer of TcHbA, designated D1 (71 548 ± 5 Da), and the heterodimer D2 (…