La rivière Yahfufah est permanente dans sa partie amont. Cinq stations situées entre 1 100 et 1 250 m d'altitude ont été prospectées. Deux séries de prélèvements, à raison d'un par mois, eurent lieu durant les années 1973-1975 et 1980-1982. L'examen des larves de Marthamea beraudi montre que le développement de cet insecte est du type semivoltin N 2. La période de vol s'échelonne entre la seconde moitié du printemps et la mi-été. La température de l'eau varie entre 9° C en hiver et 15° C en été.

En Suisse, les cours d'eau de types variés du Jura, des Préalpes et des Alpes ont encore une faune plécoptérique relativement intacte. Par contre, ceux des régions agricoles et industrielles du Plateau ont perdu la moitié de leur faune dans leur cours moyen et même parfois la totalité dans leur cours inférieur. L'atlas des Plécoptères donnera, par la méthode des quadrats, l'état actuel de nos connaissances sur la distribution géographique et sur l'écologie des espèces de Suisse.

Two new taxa from the Province of Córdoba, Brachyptera vera cordubensis nov. ssp. and Capnioneura gelesae nov. sp., are described and illustrated. The phyletic relationships of Leuctra andalusiaca Aubert are discussed.

Records for fifteen species of stoneflies (Amphinemura sulcicollis, Nemoura avicularis, Nemoura cinerea, Nemurella pictetii, Protonemura meyeri, Leuctra fusca, Leuctra hippopus, Leuctra inermis, Capnia atra, Capnia bifrons, Diura bicaudata, Isoperla grammatica, Perla bipunctata, Chloroperla tripunctata and Siphonoperla torrentium) from the Corrib catchment basin in the west of Ireland are presented. Their distributional patterns are considered in relation to habitat characteristics, including water chemistry, and the general topographical and geological features of the area. Predation by fish on stoneflies in alkaline streams was also investigated.

Deux nouvelles espèces de Plécoptères pour la faune de France (Rhabdiopteryx thienemanni - Taeniopterygidae et Leuctra pasquinii - Leuctridae) ont été découvertes dans le Sud-Est. Leurs présences dans cette région soulignent l'affinité de cette zone avec les pays méridionaux voisins, l'Espagne et l'Italie, où le Taeniopterygidae espagnol et le Leuctridae italien étaient considérés jusqu'alors comme espèces endémiques.

A second species of the genus Macrogynoplax, hitherto known only from northern South America, is described from the State of São Paulo, in southeastern Brazil.

Nymphs of the three perlid genera known from southeastern Brazil, Anacroneuria, Kempnyia and Macrogynoplax, are distinguished morphogically and a key is provided for their determination.

The distribution of 37 species of Plecoptera in the Spanish area of the Duero basin is studied. A factorial analysis of the data indicates that current and substrate are the major factors controlling the distribution of the stonefly nymphs in the area. Water temperature and periodical drought have also a marked influence on such distributions.

The egg of S. longa is described and illustrated (SEM micrographs).

Fifteen stonefly species were found in the streams of the Świȩtokrzyski National Park (Lysogóry chain of the Świȩtokrzyskie Mts) ; among them Protonemura intricata, Pr. praecox and Leuctra hippopus were found for the first time in this area. Clear difference between the stonefly fauna of the northern and southern slopes were observed.

The samples of emerging stoneflies obtained using slit traps indicated a three-phase course of emergence : early spring (two winter stoneflies), early summer (especially Perloidea) and autumn (a few abundant Nemouroidea). Early June and middle August are recommended as the sampling periods for benthon as far as stoneflies for bio-index studies are concerned.

The endemic Megaleptoperla diminuta (Plecoptera : Gripopterygidae) was numerous on introduced watercress, Nasturtium microphyllum in Waikoropupu Springs, New Zealand. Adult females laid eyed ova. There appear to be about 15 nymphal instars and a non-seasonal, one year life cycle. Ovoviviparity and viviparity in Australian and New Zealand Plecoptera and Trichoptera may be associated with seasonal aquatic vegetation and fluctuating water levels.

Since 1978 a sampling program is being conducted on various basins of Catalonia (NE-Spain), covering the whole of the basins of the rivers Tordera, Llobregat, Besòs, Ter, Foix and Segre (Andorran rivers included). A total of 51 species of Plecoptera has been collected in a range of altitudes from 100 m to 2 250 m. Among them, there are stenothermal species of high altitude and a group of species that live in temporary water courses. Some species of Leuctridae, Capniidae and Chloroperlidae are members of the interstitial fauna in some instars of their life.

Für die Art Isoperla grammatica Poda, 1761 wird ein Neotypus beschrieben. Die Männchen dieser Art sind sowohl durch ihre Trommelzeichen als auch durch die Strukturen des Aedeagus zu erkennen, die Weibchen können über die Strukturen der Vagina bestimmt werden. Die Art wurde bisher in den Alpen (an der Drau) und in den Pyrineen (Pyrénées Orientales) gefunden.

Three species of Isoperla occur in Fennoscandia. The most common is I. grammatica, although it has not been recorded above the subalpine vegetation belt. I. difformis has a similar distribution, but is less common. I. obscura occurs mainly at high latitudes and altitudes, although it is also abundant in large rivers. Eggs were reared at temperatures of 4, 8, 12, 16, 20 and 24° C. I. difformis did not hatch at 4° C. I. grammatica at 4 and 8° C while I. obscura did not hatch at 16° C and above. Egg mortality was high in I. difformis at 24° C. Incubation period decreased with increase in temperature and varied between 28 and 68 days in I. grammatica and between 15 and 83 days in I. difformis. For I. grammatica and I. difformis, the relationship between the egg incubation period and the water temperature was linear on logarithmic scales. For I. obscura, no such relationship was found and the mean incubation period at all temperatures was 305 ± 57 (S.D.) days. Explanations are presented to explain these differences in egg incubation characteristics.

A new classification of Perlodinae (sensu Zwick 1973) is proposed in which three tribes are recognized. Arcynopterygini Ricker & Scudder includes genera whose eggs are circular in cross section while Perlodini Klapálek and Diploperlini, new tribe, include genera whose eggs are triangular or semicircular in cross section.