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Coiled nautiloids of the Tournaisian and early to middle Viséan (Early Carboniferous) have so far only become known from a few regions. Here we describe material from five localities in southern Algeria; these belong to four stratigraphic horizons (two horizons in the late Tournaisian, one horizon near the Tournaisian–Viséan boundary, one horizon in the early to middle Viséan). From these, the new genera Stroborineceras gen. nov. and Trilobitoceras gen. nov. and the following new species are described: Rineceras tenerum sp. nov., Stroborineceras insalahensis gen. et sp. nov., Stroborineceras felis gen. et sp. nov., Stroboceras mane sp. nov., Stroboceras ancilis sp. nov., Vestinautilus angulatus sp. nov., Vestinautilus papilio sp. nov., Vestinautilus inflexus sp. nov., Vestinautilus bicristatus sp. nov., Trilobitoceras peculiaris gen. et sp. nov., Aphelaeceras azzelmattiense sp. nov., Maccoyoceras saharensis sp. nov., Maccoyoceras habadraense sp. nov. and Maccoyoceras concavum sp. nov.
Early Carboniferous coiled nautiloids from North Africa are virtually unknown. An assemblage of nine species, all from the family Trigonoceratidae, from the Dalle à Merocanites (Tournaisian-Viséan boundary interval) of Timimoun in western Algeria is described, being the most diverse Carboniferous nautiloid assemblage known from North Africa but much less diverse than the time-equivalent assemblages from Belgium and Ireland. The assemblage consists of the species Maccoyoceras pentagonum sp. nov., Lispoceras orbis sp. nov., Thrincoceras devolvere sp. nov., Rineceras multituberculatum sp. nov., Rineceras rectangulatum sp. nov., Vestinautilus padus sp. nov., Vestinautilus concinnus sp. nov., Planetoceras destrictum sp. nov. and Planetoceras transforme sp. nov. A morphometric analysis of Maccoyoceras pentagonum sp. nov. and Lispoceras orbis sp. nov. shows that the intraspecific variation in these species is within rather narrow limits.
Macaronesia, with the exception of the Azores, is one of the few Palearctic provinces where basic taxonomic information on the freshwater copepods is still lacking. We redescribed Eucyclops azorensis, a cyclopid crustacean so far known only in the Azores, and report the occurrence of this species in Algeria and Madeira Island. Eucyclops azorensis was formerly considered to be a subspecies of E. agiloides (East Africa); therefore, the latter species is redescribed here as well based on type and non-type material. Morphological comparisons between E. azorensis, E. agiloides and other taxa (E. serrulatus and E. roseus), assumed to be closely related to our target species, support a closer relationship between E. azorensis and E. serrulatus (Palearctic) than between E. azorensis and E. agiloides (Afrotropical). The slight differences between E. azorensis and E. serrulatus in the surface ornamentation of the antennal coxobasis and intercoxal sclerites of legs 1 and 4 suggest a relatively young separation of these lineages. Eucyclops agiloides is morphologically close to E. roseus (temperate and subtropical Asia, southeastern Europe, East Africa). The numerous and clear-cut differences indicate a species rather than subspecies-level differentiation between E. agiloides and E. roseus, unlike what was formerly proposed in the taxonomic literature.