Vanfleteren J. R. (2006). A redescription of Eucyclops serrulatus (Fischer, 1851) (Crustacea: Copepoda: Cyclopoida) and some related taxa, with a phylogeny of the E. serrulatus -group. -Zoologica Scripta, 35, 123-147 . Eucyclops serrulatus (Fischer, 1851) , the type species of the genus Eucyclops , is redescribed from specimens found in the St. Petersburg area, Russia (type locality) and compared with specimens from Siberia, western Europe and North Africa. A neotype is selected. Cultures were set up, and interpopulation hybridization as well as hybridization with related species was attempted. The classical description of external body morphology was combined with pore signature mapping and with DNA nuclear small subunit (18S) ribosomal gene sequence analysis.Comparisons with E. dumonti Alekseev, 2000 , E. hadjebensis Kiefer , E. speratus Lilljeborg , E. turcomanus Lindberg, and E. pectinifer (Cragin, 1883) were carried out. A phylogenetic tree based on molecular information shows that E. serrulatus and E. speratus should be regarded as separate species. E. dumonti also deserves species status, but not E. hadjebensis . A cladistic tree based on the pore pattern of the cephalosome agrees well with a tree based on the sequence of the 18S rDNA gene. Cephalosome (and probably metasome) pore patterns seem useful to elucidate relationships within genera, while urosomal pore patterns better reflect the relationship between genera. E. serrulatus occurs in three morphological forms over most of its range; one of these (C) might be a rare ('recessive') morphotype, while forms A and B differ in microhabitat choice, but hybridize when living together. The same polymorphism also occurs in an American species ( E. prionophorus ), and therefore two hypotheses regarding its origin are advanced: either forms A and B evolved during the glacial episode (Pleistocene origin), separately on both sides of the Atlantic, or the polymorphism was already present in the ancestor of the serrulatus -group, and was later lost in some but not in all species (Pliocene origin.) Victor Alekseev,

The group of hyponeustonic daphniid cladocera previously known under the generic name Scapholeberis is raised to the rank of a subfamily (Scapholeberinae) and contains two genera, Megafenestra n.gen. (2 species), and Scapholeberis s.s. (7 species and one subspecies). The characters upon which this revision is based are: structure of the rostrum, structure of the first antennae, structure of trunk limbs 1, 2, and 5, presence and nature of headpore(s), structure of the ventral rim of the valves, armature of the distal rim of the valves, structure of the postabdomen and its end-claws. Males were examined in all but two species, and proved to be more primitive than females and much less diagnostic than in the Chydoridae. It also appeared that the shape and armature of the postabdomen are less important taxonomical tools than heretofore supposed. In more than half of the species, it is of generalised shape and hardly usable beyond the species-group level. The same, although less drastically, holds true for the P 1 of males. Of greatest diagnostic value at the species level are the shape of the rostrum and the armature of the valve margins.

In samples from 62 localities in Tunisia and La Calla area in N .E. Algeria, 56 species of Entomostraca were found . More than half of these are widespread and give little insight into the origin of the regional fauna . A few are endemic to the area and three groups are of relictual nature.

48 species of Phyllopoda, 24 species of Copepoda, and a freshwater shrimp are reported from Mali. Morphologically noteworthy or little known species are figured. Daphnia barbata and D. dolichocephala are redescribed. Three West-African species of Tropodiaptomus were found. T. senegambiae is synonymised with T. banforanus. Thermodiaptomus yabensis is fully figured. The distribution of T. yabensis and the regional Tropodiaptomus is discussed. A general biogeographical discussion is not yet possible, because for many species, and particularly Cladocera, both taxonomical position and chorological records are fragmentary and uncertain. At least 29 species, however, seem to be restricted to Africa, and some even to West Africa.The water chemistry of the lakes of central Mali is characterized by a low mineral content, but seems not to be distributive to any of the numerous zooplankton species encountered.The zooplankton communities, especially in the lakes of the internal delta of the Niger, are typically composed of numerous species. Among copepods, it is usual to find three or four genera to co-occur, and each genus may be represented by up to three species. This indicates long-term instability of the communities, and suggests strong interspecies competition to be present. This is corroborated by an analysis of the ranges of some African endemics.It is shown that the Niger delta is part of the biological boundary of the Sahara as far as aquatic invertebrates are concerned. West African equatorial climate endemics (e.g. 3 Tropodiaptomus species, Thermodiaptomus yabensis), and arid to semi-arid climate endemics (Daphnia barbata, D. longispina, Metadiaptomus mauretanicus) meet and interpenetrate each others' ranges over a short distance.

Twenty species of Cladocera are reported from the Nile, where lacustrine species dominate, and from Jebel Marra and the Red Sea Hills, where chydorids dominate. The community found in the Red Sea Hills is more typically desertic than that of Jebel Marra, which appears closely related to the fauna of the West and Central African Sahel.