Search results for "Arthropod mouthparts"
showing 8 items of 8 documents
The systematic position of Ergasticus (Decapoda, Brachyura) and allied genera, a molecular and morphological approach
2013
13 pages, 7 figures, 2 tables
The 40-Year Mystery of Insect Odorant-Binding Proteins
2021
International audience; The survival of insects depends on their ability to detect molecules present in their environment. Odorant-binding proteins (OBPs) form a family of proteins involved in chemoreception. While OBPs were initially found in olfactory appendages, recently these proteins were discovered in other chemosensory and non-chemosensory organs. OBPs can bind, solubilize and transport hydrophobic stimuli to chemoreceptors across the aqueous sensilla lymph. In addition to this broadly accepted “transporter role”, OBPs can also buffer sudden changes in odorant levels and are involved in hygro-reception. The physiological roles of OBPs expressed in other body tissues, such as mouthpar…
Local reactions to tick bites
2008
A retrospective histological and immunohistochemical study has been carried out in 25 cases of tick bites recorded in our Departments. The samples that included an attached tick showed a cement cone anchoring the mouthparts to the skin and a blood-soaked, spongiform appearance of the superficial dermis, with a mild neutrophilic and eosinophilic infiltration. The vessels displayed a loose multilayered endothelial proliferation, with plump endothelia, permeated with erythrocytes. A few of them were severed, allowing copious blood extravasation. The established lesions included the following: erythema chronicum migrans-like cases, foreign body granulomas-sometimes containing remnants of the mo…
Toxic Proteins and Peptides
1994
Many animals produce poisonous substances which, even at a relatively low dose, are deleterious or lethal to other organisms, including man. They may serve on the one hand to disable or kill prey, or on the other hand as a protection or defence against predators. These substances are mostly produced by special glands, and both poison reservoirs and specialized structures for delivering the secretion, e.g. stings or modified mouthparts or fangs, are usually also present. In accordance with the aims of this book, we will deal with the comparative biochemistry of the animal toxins as natural products with special structures and functions; a discussion of the mechanisms of their pharmacological…
Avian mite dermatitis: an Italian case indicating the establishment and spread of Ornithonyssus bursa (Acari: Gamasida: Macronyssidae) (Berlese, 1888…
2015
Background Avian mite dermatitis is a skin disease caused in mammals by the incidental bites of blood-sucking mites which customarily parasitize wild and domestic birds. It manifests in the form of pruritic, erythematous, or urticarial papules, with a central sting mark, in skin regions normally covered by clothing. The species mainly implicated in human bite cases are Dermanyssus gallinae, Ornithonyssus sylviarum and, less frequently, Ornithonyssus bursa. The latter is mainly a tropical and subtropical mite and its – presumably transitory – presence has been recorded only once in Europe, in migratory birds. Case report We report a case of avian mite dermatitis in a 70-year-old man, an owne…
Phylogeny of Hyadinini (Diptera: Ephydridae) with an Emphasis on Structures of the Proboscis
2014
Abstract. The shape of adult mouthparts (proboscis) of all genera of Hyadinini (Diptera: Ephydridae) is provided, including variability of cibarium, lacinia and the number of pseudotracheae. Its usage in phylogenetic construction is documented. All ten genera are diagnosed, including the genus Lytogaster, which is formally restored from synonymy with Hyadina. The ventral receptacle of four genera (Garifuna, Parahyadina, Parydroptera and Pelinoides) and the male terminalia of Parahyadina are presented for the first time. Monophyly of the tribe is discussed and the relationships among genera of Hyadinini are proposed. Ten Hyadinini genera are grouped into four lineages 1) Pelina group with Pe…
The Centetostoma scabriculum complex—a group of three cryptic species (Arachnida: Opiliones: Nemastomatidae)
2011
Nemastoma scabriculum Simon, 1879 turned out to be a group of three closely related species of the Pyrenees in SW Europe (France and Spain). Though the species are similar in general habit they can easily be recognized by external morphology (structure of the apophysis of male chelicerae) and male genital morphology (penial structure). For Nemastoma scabriculum Simon, 1879 sensu stricto a lectotype is designated. The synonymous Nemastoma ventalloi Mello-Leitao, 1936 is considered to be a distinct species and is re-described. The third species of the group is described as new, Centetostoma juberthiei sp. n. Though partly sympatric in their restricted Pyrenean area, the individual species are…
Cephalic anatomy of Sinentomon erythranum Yin (Protura : Sinentomidae)
1992
Abstract The structure of the head capsule, endoskeletal structures, oral folds, mouthparts, foregut, maxillary and labial glands, and the central nervous system of the Chinese proturan Sinentomon erythranum Yin (Protura : Sinentomidae) have been described. The most significant features are the unusual thickness of the cuticle with numerous serrated lines, the reduction of sutures and the absence of linea ventralis, the simplification of gnathal pieces, and the reduction of the musculature. A comparison with other Protura and Apterygota leads to some morphological and phylogenetical interpretations of the cephalic structures, in particular those concerning the entotrophy.