Cleaning interactions between the wrasse Symphodus melanocercus and brown meagre Sciaena umbra are documented from observations whilst free diving on a shallow rocky reef in the central Mediterranean Sea. Cleaning events occurred at cleaning stations mainly during the morning and gradually decreased in the evening. The body parts mostly cleaned were the opercular region and the fins, possibly as gnathiid isopods preferentially attach to these areas.

This study was conducted in the Knuckles Forest Region in central Sri Lanka, and investigated how termite species richness, abundance and functional group diversity vary in different montane forest types and identified the likely causes of this pattern. Termite diversity declined with increased elevation, with upper montane forests recording a single endemic species, Postelectrotermes militaris Desneux. Transect sampling in lower montane forests yielded 26 species, with a higher number from dry forests (22 species) than from wet forests (15 species). Species specificity also was high in dry forests (11 species) compared with wet forests (four species). Termite abundance did not show a distinct trend in dry and wet forests. Live-wood termites were present only in upper montane and high-altitude lower montane dry forests. Wet forests had a higher relative abundance (78%) but not species richness (40%) of soil and soil–wood interface feeders. In dry forests, both species richness (82%) and abundance (88%) of fungus-growing wood feeders were higher. The study suggests that key drivers of the species distribution pattern are low temperature and differing forest floor conditions. In the upper montane forest floor where earthworms dominate, wet soil and damp, woody litter riddled with beetles are not favourable for termites. In lower montane wet forests, moist, thick decomposing leaf litter and in dry forests, drier, relatively undecomposed leaf litter with many dry sticks and branches support species with specific food habits.

Extensive beds of the mussel Perumytilus purpuratus are a common feature of the mid-intertidal along the Chilean coast. The beds are an alternative stable state that results from the anthropogenic removal of the keystone predator Concholepas concholepas. The mussel beds constitute an important microhabitat that supports a large number of small mobile macrofaunal and meiofaunal species. This paper seeks to determine if the absence of extensive mussel beds within a Marine Reserve results in a reduced species richness. We used ‘live’ artificial mussel beds on plates to determine the species richness of fauna both inside and outside the Marine Reserve. There were no significant differences in the species richness (Smean) on plates inside and outside the Marine Reserve but there were differences with the natural mussel beds. Though the assemblages on the plates did not reach maturity ‘live’, artificial mussel beds could prove a useful tool for assessing the species richness of small mobile macrofauna and meiofauna.

Three microhabitat types (dead coral fragments, coral gravel and coral sand) were distinguished and sampled at two locations (Matemwe and Makunduchi) in a tropical lagoon (Zanzibar Island, Tanzania), and the community structure, habitat preferences and biodiversity of the associated harpacticoid copepod fauna was investigated. The harpacticoid fauna is affected by sediment granulometry and by the structural differences between coral and both gravel and sediment. The coral fragments contained a specific assemblage composed of typical ‘phytal’ taxa (Tisbe, Paradactylopodia and Dactylopusia) along with other eurytopic and sediment-dwelling forms (Ameira, Ectinosoma and Amphiascus), which may be attracted by the sediment retained between the coral branches. The assemblages of coral gravel and upper sediment layer did not differ significantly from each other and had mostly the same dominant genera. The sediment from Matemwe was dominated by the interstitial Paramesochridae and the sediment from Makunduchi by Tetragonicipitidae. The coral fragments from Makunduchi sustained a more diverse assemblage than gravel and the different sediment layers. It was assumed that coral form and complexity, with implications for habitable space, nutritional resources and level of predation, are important in structuring diversity of the associated assemblage.

Les modèles biologiques constituent un élément fondamental de la méthode des microhabitats pour l'évaluation de la capacité d'accueil potentielle des cours d'eau vis-à-vis des organismes aquatiques. Avec l'importance croissante de la problématique «habitat» dans les études d'impact est apparue la nécessité de disposer d'outils informatiques performants pour la réalisation des calculs complexes et fastidieux qui en découlent. ProCURVE est un logiciel entièrement dédié à la construction de courbes depreferenda et de profils écologiques pour les organismes aquatiques. Il élabore ces modèles biologiques en accompagnant l'utilisateur dans une démarche analytique logique et rigoureuse. Le logiciel permet une gestion aisée des données. La souplesse de la base de données relationnelles lui confère de nombreuses possibilités d'analyses linéaires ou transversales. Son ouverture surles bases de données externes permet d'envisager le traitement de données déjà disponibles dans la bibliographie. Les variables écologiques utilisées communément sont fournies par défaut mais l'utilisateur a la possibilité de les configurer selon ses besoins. Les résultats générés sont visualisés directement. Ils peuvent être sauvegardés sous forme graphique ou exportés au format des principaux tableurs pour un traitement complémentaire.

1. The importance of microhabitat characteristics for macroinvertebrate microdistribution was studied within a reach of themain channel of the Upper Rhône River (France). 9 locations (3 on the left hand side, 3 across the middle, and 3 on the righthand side) were sampled twice on two dates (as duplicates in June and July 1982). From 19 variables, including substratum andhydraulic parameters, 14 were selected to describe the physical habitat of each location. 47 macroinvertebrate species were collectedby means of dredging with a modified Rallier du Baty dredge. The habitat-fauna co-structure was studied using co-inertiaanalysis.2. The river reach was transversally asymmetrical : shallow on one side (up to 2.80 m) with coarse sediments rich in periphyton,and much deeper on the other side (up to 4.80 m) with a gravel bottom rich in organic particles. In the middle of thechannel these conditions were intermediate, but the current was stronger. Velocity and the other hydraulic parameters variedindependently of the substratum characteristics. This independence is a consequence of old man-made impoundments (inheritedstructures) and perhaps of present paving of the substratum also.3. The macroinvertebrate fauna was closely linked to this transverse asymmetry of the reach, with the highest richness andabundance to the shallow side of the channel and the lowest species richness in the rapid central part. The most significant faunisticdifferences were linked i) to water depth, acting on both hydraulic parameters and periphyton (by light transmission), ii)to the inherited old bottom substratum, and iii) to a lesser extent, to the present current velocity.

Studies were commenced to collect and identify the phlebotomine sandflies found in Nairobi. These studies were also aimed at determining their numbers as well as assessing the effects of seasonal changes on the sandfly population. Four trapping methods, namely, light traps, sticky traps, aspiration and human bait were employed. Eight species and one undescribed species were recorded over a period of 6 months. The identified species included Phlebotomus guggisbergi (Kirk and Lewis), P. rodhaini (Parrot), Sergentomyia adleri (Theodor), S. harveyi (Heisch, Guggisberg and Teesdale) and S. bedfordi (Newstead) and an undescribed species. Most of the sandfly species trapped showed seasonal prevalence. The seasonal variation was closely related to the weather conditions. Sandflies were found in termite mounds, animal burrows, caves and dugouts some of which were near human habitations. Termite mounds and animal burrows were the most preferred habitats.