Search results for "Orchestia"
showing 8 items of 8 documents
A finding at the Natural History Museum of Florence affords the holotype designation of Orchestia stephenseni Cecchini, 1928 (Crustacea: Amphipoda: T…
2017
The beach flea Orchestia stephenseni has been originally described by Cecchini twice (1928, 1929) from the La Spezia type locality (northern Tyrrhenian Sea, Italy), and successively re-described by Karaman (1973) and Iaciofano & Lo Brutto (2016).
Re-description of Orchestia stephenseni Cecchini, 1928: designation of neotype and senior synonym to Orchestia constricta A. Costa, 1853 (Crustacea: …
2016
The beach flea Orchestia stephenseni was originally described by Cecchini (1928), and successively by Karaman (1973). The description of this species will be herein revised by focusing on the variation of the g nathopod 2 in males, as detected during its growth period. An analysis of DNA Barcoding was performed to support the assignment of the taxonomic species to five morphotypes. As the type specimen has not yet been designated, a neotype is assigned. The name of the species is here presented as a valid name as it satisfies the requirements of a Reversal of the Principle of Priority: Orchestia stephenseni takes precedence over the objective synonym Orchestia constricta A. Costa, 1853, in …
Production, fonction et localisation d'Orchestine: calciprotéine spécifique de la matrice organique des structures minéralisées élaborées par le crus…
2002
As most Crustaceans, Orchestia cavimana possesses a mineralized exoskeleton which is periodically replaced. Because of the terrestrial behaviours of this animal, this molting cycle is related to calcium storage and resorption processes. Calcium storage occurs, as calcareous concretions, in diverticula of the midgut called posterior cæca. Calcareous concretions are essentially composed of amorphous calcium carbonate precipitated within a proteinaceous organic matrix composed of a soluble fraction and an insoluble one in an EDTA-buffer. Among the soluble components of the organic matrix, a previous study led to characterize a polypeptide of 23 kDa in SDS-PAGE called Orchestin. This protein, w…
Some effects of salmon calcitonin on calcium metabolism in the crustaceanOrchestia during the molt cycle
1989
In the terrestrial amphipod Orchestia cavimana, investigations of the variations of the total hemolymphatic calcium during the normal molt cycle revealed that a calcium balance is maintained in intermolt, as observed in numerous crustaceans. During premolt, hypercalcemia occurs, related to the marked calcium reabsorption from the old cuticle, which may promote the storage of a part of this calcium within the midgut posterior caeca. The calcium levels fall after exuviation to late postmolt to the low basal levels of intermolt; this may reflect the imbalance between the rates of calcification of the newly secreted cuticle and uptake of calcium within the posterior caeca. Administration of sal…
Fine Determination of the Molt Cycle Stages in Orchestia cavimana Heller (Crustacea: Amphipoda)
1986
ABSTRACT The successive stages of the molt cycle of the terrestrial crustacean amphipod Orchestia cavimana are finely described and illustrated in order to give precise reference marks for experimental, physiological, and biochemical studies. The method of determination, very rapid and easy, is based upon the observation of the morphogenesis of the dactylopodite and the propodite from the third pereiopod. The events of the early morphogenesis of the claw from the dactylopodite divide the intermolt period C into four stages. The formation of spines and the secretion of the epicuticle and then the procuticle at the level of the propodite divide the premolt period into seven stages. The entire…
Variations in haemolymph ionized calcium concentrations in the crustacean Orchestia cavimana during a moult cycle
1993
Abstract Measurements of ionized calcium concentration in the haemolymph of the semi-terrestrial crustacean Orchestia cavimana were taken during the 14 successive moulting stages by ion-selective electrode direct potentiometry on pooled samples. Ionized calcium showed major variations associated with the moult cycle. Titres were low and relatively stable in intermoult and early premoult, then progressively increased during mid and late premoult to reach maximal values just at exuviation, and rapidly fell down during the postmoult. The variations of the ionized fraction showed a close correlation with those of the calcaemia (= total fraction), suggesting the presence of efficient haemolympha…
Variations of vitamin D-like reactivity in the crustacean Orchestia cavimana during the molt cycle
1991
An investigation into vitamin D-like molecules has been performed on whole extracts of the terrestrial amphipod Orchestia cavimana, using a sensitive nonequilibrium assay employing 1,25-(OH)2 D receptor from calf thymus. Relatively large amounts of these secosteroid-like molecules were observed and they varied in concentration according to the stages of the molt cycle. The amplitude of these variations reaches a ratio of about 40 from the minimum in premolt to the intermolt sharp peak.
Orchestin, a calcium-binding phosphoprotein, is a matrix component of two successive transitory calcified biomineralizations cyclically elaborated by…
2003
Orchestia cavimana is a crustacean that cyclically replaces its calcified cuticle during molting cycles in order to grow. Its terrestrial way of life requires storage of calcium during each premolt period, as calcareous concretions, in tubular diverticula of the midgut. During the postmolt period the stored calcium is reabsorbed and is translocated through the storage organ epithelium as calcified small spherules. In a previous study, we sequenced and characterized a remarkable component of the organic matrix of the premolt storage structures, Orchestin, which is a calcium-binding phosphoprotein. In this paper, we analyzed the spatiotemporal expression of the orchestin gene by Northern blot…