In palaeontological and archaeozoological studies dealing with tilapia remains, identifications are usually limited to the level of the tribe Tilapiini (now called Haplotilapiini). In the present study, dry skeletons of Oreochromis niloticus (Linnaeus, 1758), Oreochromis aureus (Steindachner, 1864), Sarotherodon galilaeus (Linnaeus, 1758) and Coptodon zillii (Gervais, 1848) were analysed with the aim of defining morphological characters on a series of isolated skeletal elements. Eighteen different skeletal elements that have good chances of being well preserved (and of being recognised as tilapia) were analysed, i.e. premaxilla, dentary, maxilla, articular, lacrimal, palatine, quadrate, hyomandibula, operculum, preoperculum, posttemporal, cleithrum, supracleithrum, urohyal, vomer, and the first three precaudal vertebrae. Diagnostic criteria are described and illustrated with figures. It appears from the comparative analysis, and also from blind tests carried out afterwards, that identification is possible except for the articular and the third vertebra. More accurate identification of fossil and subfossil finds of Haplotilapiini should allow a better documentation of the zoogeographical history of these taxa in the future.
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RBINS Staff Publications 2017
1.Migratory species depend on ephemeral environmental conditions; thus, species distribution modelling (SDM) must incorporate phenological changes along migratory routes. Our overarching goal was to model habitats for three waterfowl species migrating through Eurasian grasslands (red-breasted goose [Branta ruficollis], taiga bean goose [Anser fabalis fabalis] and Bewick's swan [Cygnus columbianus bewickii]) while accounting for ephemeral environmental conditions. Our objectives were (a) to develop a workflow of mapping ephemeral environmental conditions, (b) model habitats for the three species and (c) evaluate the protection status of habitats in natural and agricultural landscapes. We expected water availability, particularly ephemeral spring waterbodies, to strongly influence these species' distributions. 2. We utilized MODIS data for phenological synchronization of Landsat images to create species-and season-specific metrics and land cover maps. We used Landsat-derived environmental variables, elevation and bird GPS locations in Maxent SDM. We compared locations of modelled habitats, protected areas and Ramsar sites. 3. Our land cover maps had an overall accuracy of 0.92–0.95 and captured ephemeral water extent during these species' migrations. All models had AUC scores of 0.89–0.94; distance to water, land cover and elevation were the most important variables. Modelled habitats were distributed unevenly and occurred in both natural and agricultural landscapes; 40%–76% fell within croplands. Although most croplands provide a rich food supply, their value as waterfowl habitat critically depended on water availability. Approximately 22% of potential habitat in the natural landscape, but only 3% in croplands, had some level of protection.
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RBINS Staff Publications 2025
