Biodiversity and bionomics of the black flies (Diptera: simuliidae) of northeastern Algeria.

Black flies in the Seybouse River Basin in northeastern Algeria were sampled at 31 sites along the main river and its tributaries across all seasons from 2011 to 2013. Eight nominal species and species complexes in three genera were identified among more than 31,000 specimens. Urosimulium faurei (Bernard, Grenier & Bailly-Choumara), Simulium (Eusimulium) mellah Giudicelli & Bouzidi, and Simulium (Nevermania) lundstromi (Enderlein) were recorded for the first time in northeastern Algeria. Three cytoforms of the Simulium (Eusimulium) velutinum complex and two morphoforms of Simulium (Nevermannia) ruficorne Macquart were found. The most abundant and ubiquitous taxon, Simulium (Wilhelmia) pseudequinum Segúy, representing nearly 80% of collected specimens, occupied the widest range of habitats, including those with anthropogenic influences.

Genetic variation in a colonization specialist, Simulium ruficorne (Diptera: Simuliidae), the world's most widely distributed black fly.

The ability of aquatic insects to colonize Earth's most remote freshwater habitats, such as those of islands and deserts, is limited to select taxa. Among black flies, the premiere colonization specialist is Simulium ruficorne Macquart, the only species known from both the Afrotropical and Palearctic regions. We investigated the cytogenetics of S. ruficorne to gain insight into its wide geographic distribution and ability to colonize oceanic islands and deserts. On the basis of larval polytene chromosomes from 14 locations, we documented 17 novel and previously known chromosomal rearrangements and established five cytoforms (A1, A2, B, C, and D), of which probably four (A1/A2, B, C, and D) are distinct species and two (A1 and A2) represent sex-chromosome polymorphism involving a heteroband in the long arm of chromosome III. The chromosome restructuring phenomena associated with the five cytoforms are consistent with the trend in the Simuliidae that one and the same rearrangement can assume different functions in the various descendants of a common ancestor in which the rearrangement was polymorphic. The most widely distributed cytoforms are A1 and A2, which are found in North Africa, the Canary Islands, and Majorca. Simulium ruficorne, the only known black fly in the Hoggar Mountains of the central Sahara Desert, represents a cohesive population of cytoform A1 little differentiated from other North African populations of A1 and A2. Cytoform B inhabits the West African mainland, cytoform C is on Tenerife, and cytoform D is on Cape Verde. We suggest that dispersal and colonization specialists, such as S. ruficorne, are multivoltine inhabitants of temporary streams, and must relocate as their habitats deteriorate. Simulium ruficorne, therefore, should have adaptations that contribute to successful dispersal and colonization, perhaps largely physiological in nature, such as tolerance of high temperatures and droughts.

Inventory of the Black Flies (Diptera: Simuliidae) of North Africa.

Published records are provided for the 52 nominal species, one undescribed morphospecies, and two cytospecies of black flies known from North Africa, with relevant literature, selected synonyms, and taxonomic comments. Morocco has the greatest simuliid diversity (44 nominal species), followed by Algeria (34 species), Tunisia (18 species), Libya (5 species), and Egypt (2 species). A new site for Simulium ruficorne Macquart is recorded for simuliid-poor Egypt.