Taxonomic diversity and structure of the molluscan fauna in Oualidia lagoon (Moroccan Atlantic coast).

The spatial distribution of the molluscan fauna of Oualidia lagoon (Moroccan Atlantic coast) was studied during winter 2013. Samples were collected from 43 stations over the whole of the lagoon. Twenty-eight taxa (19 species of gastropods, 7 species of bivalves, 1 species of polyplacophora, and 1 species of cephalopod) were listed, 21 of which are newly reported for Oualidia lagoon. Four taxa, Hydrobia sp. (78.29%), followed by Abra alba (13.99 ), Nassarius pfeifferi (5.07%), and Cerastoderma edule (1.32%), were accounted for 98% of the total abundance. A classification analysis used to characterize the lagoon on the basis of molluscs showed the existence of three main clusters from downstream to upstream: a Nassarius pfeifferi community, a Hydrobia sp.-Abra alba community and a Hydrobia sp.-Cerastoderma edule community.

[Torticollis after unnoticed pharyngeal perforation: suspected retropharyngeal abscess]. / Tortícolis tras perforación faríngea inadvertida: sospecha de absceso retrofaríngeo.

Pharyngeal perforations due to foreign bodies are severe when retropharyngeal space infection develops into an abscess. Although the common clinical presentation is sore throat and fever, when the perforation remains occult, torticollis can be a significant symptom. Palatopharyngeal lesions, caused by rigid objects' impactation through the mouth, are common in childhood. Most are not important, but all have the potential hazard of pharyngeal perforation with development of a retropharyngeal abscess. It must be suspected specially when air is shown in the retropharyngeal space on a lateral radiography of the neck, which should always be done. We report a 9-years old boy who had cervical stiffness and torticollis and elevation of the right shoulder, without previous known trauma. Air was shown in the retropharyngeal space on a lateral radiography of the neck in relation to a possible pharyngeal perforation which was later confirmed by a CT scan. We review the literature about diagnosis and treatment of retropharyngeal abscess in childhood.