The effects of wave action and horseshoe crab spawning on the topography and grain-size characteristics on the foreshore of an estuarine sand beach in Delaware Bay, New Jersey, USA were evaluated using data collected over six consecutive high tides. Data were gathered inside and outside a 25 m long exclosure constructed to create a control area free of disturbance by crabs. The density of crabs...

Abstract Horseshoe crabs as a group are renowned for their morphological conservatism punctuated by marked shifts in morphology associated with the occupation of non-marine environments and have been suggested to exhibit consistent developmental trajectory throughout evolutionary history. Here, we report new species horseshoe crab from Ordovician (Late Sandbian) Kingston, Ontario, Canada, juven...

Biomedical companies catch and bleed horseshoe crabs for the production of Limulus amebocyte lysate (LAL), a product used for protecting public health (Berkson and Shuster, 1999). LAL is a clotting agent, derived solely from horseshoe crab blood cells, which is used to detect the presence of pathogenic gramnegative bacteria in injectable drugs and implantable medical and dental devices (Mikkels...

The high molecular weight hemocyanin found in the hemolymph of the horseshoe crab, Limulus polyphemus, is composed of at least eight different kinds of subunits. Ion exchange chromatography at high pH in the presence of EDTA yields five major zones, hemocyanins I to V, three of which are electrophoretically heterogeneous. The subunits have similar molecular weights, 65,000 to 70,000, and their ...

Factor G, a coagulation proenzyme of the Japanese horseshoe crab (Tachypleus tridentatus), is extremely sensitive to (1-->3)-beta-D-glucan, which is a characteristic cell-wall constituent of fungi. Using this factor and by a digestion study with (1-->3)-beta-D-glucan, we showed that blood from patients with deep m ycosis contains the glucan. It was detected in 39 out of 41 fungal febrile episod...

Receptor units in the eye of the horseshoe crab are more sensitive to lateral inhibition at some levels of excitation than they are at others. As a result, the steady-state inhibition of the response of a given unit is not directly proportional to the response levels of neighboring units. This effect may be represented by the introduction of a nonlinearity in the Hartline-Ratliff system of equa...

masses of 31 kDa. The serological specificity of the purified lectin was specifically inhibited by siatic acids sialoglycoproteins, but not by neutral sugars, hexosamines, IV-acetylhexosamines, or asialoglycopreteins. A]though the N-terminal amino acid sequence of the 1ectin from T. gigas was identical to that frem American horseshoe crab (liphemin) by the same pllrification method and cross re...

A non-contact optical method for minimally invasive neural recording is designed and implemented. This method is based on phase-resolved spectral domain optical coherence tomography (SD-OCT). The optical electrode system is calibrated by performing phase measurements from a glass slide and some preliminary experiments of optical imaging and phase measurements in optic nerve of Limulus polyphemu...