The use of chitin as raw material to obtain glucosamine hydrochloride at laboratory level was investigated. Chitin was extracted from shrimp shells by deproteinization, demineralization and depigmentation. Afterwards, glucosamine hydrochloride was produced in four main stages: (1) acid hydrolysis of chitin with 12 M hydrochloric acid using the reflux technique; (2) filtration of the solution to...

Although recognition behavior is central to many aspects of an organism’s biology, it has been difficult to effectively identify the individual recognition components (i.e., production, perception, and action) for most organisms. Among hermit crabs, a relatively well-studied system for recognition behavior, the precise shell cues that stimulate crabs to explore and choose empty shells are uncle...

Abstract Phosphate-shelled brachiopods differ in filter-feeding lifestyle, with Lingula anatina an active infaunal burrower, and Discinisca tenuis a shallow marine epibenthic animal. The shells of these animals are built organophosphatic constituents, the organic fibres/sheets reinforced calcium phosphate to provide sophisticated ultrastructural robustness. This investigation examined nature fi...

In southern Atlantic studies on hermit crab biology are scanty considering the local biodiversity. In this way, some population features of Paguristes calliopsis Forest and Saint Laurent, 1968 such as size frequency distribution, sex ratio and shell occupation in the natural environment were studied. Specimens were collected by means of scuba methods in the infralittoral area of the Anchieta Is...

Induced defenses of prey have become widely recognized in several marine taxa, yet their specificity to particular predators and impacts on subsequent predation are seldom investigated. In this study, Mytilus edulis showed highly specific induced defenses in response to predators with different attack strategies. The mussels developed significantly heavier shells only in the presence of waterbo...

Patagurus rex gen. et sp. nov., a deep-water pagurid hermit crab, is described and illustrated based on a single specimen dredged from 400 m off Moorea, Society Islands, French Polynesia. Patagurus is characterized by a subtriangular, vaulted, calcified carapace, with large, wing-like lateral processes, and is closely related to two other atypical pagurid genera, Porcellanopagurus Filhol, 1885 ...

Soft shell crab farming has been practiced in south-east Asian countries such as Indonesia. Soft shell crabs are harvested when they have just molted to prevent their shells from being hardened. An issue arises when feeding the crabs. Farmers need to feed the crabs 5% food of their body weight. However, farmers sometimes provide incorrect amounts of food to the crabs. If farmers feed the crab e...

Hermit crabs hide into shells when confronted with potential dangers, including images presented on a monitor. We do not know, however, what hermit crabs can see and how they perceive different objects. We examined the hiding response of the Caribbean hermit crab (Coenobita clypeatus) to various stimuli presented on a monitor in seven experiments to explore whether crabs could discriminate diff...

Several human pathogens and fecal-pollution indicators may persist as viable organisms in natural environments, owing to their ability to activate different types of survival strategies. These strategies include adhesion on both abiotic and biotic surfaces and the entrance to the so-called viable but nonculturable (VBNC) state. In an 18-month survey for the detection of enterococci in both lake...