Contribution à la connaissance des leuctridae [Plecoptera]

Abstract

1.1. - The male of Pachyleuctra bertrandi differs from that of P. benl-locli in the shape of the specillum, the tenth abdominal tergum and the tergal processus on the fifth abdominal segment. 1.2. - The separation of the genera Leuctra and Pachyleuctra occurred after the isolation of the genus Tyrrhenoleuctra. 2.1. - Old nymphs of Leuctra major were captured in the interstitial hyporheic biotope. 2.2. - The nymph of L. major is long and worm-like with short, slender legs and with fewer hairs and pigmentation than the other nymphs of the genus. 2.3. - The adult of L. major is elongate and the legs are normal but it has many more and stronger hairs than other Leuctra. The inhibition cf the trichogen cells during the nymphal life is compensated for by greater secretion during the last instar. 2.4. - The study of the phylogenetic relations of L. major shows several steps in the acquisition of the morphological adaptations to the interstitial biotope. 3. - The styles of the paraprocts of Leuctra fusca and L. hippopus do not penetrate the female genital cavity during copulation. 4. - Leuctra maroccana, a new species for the French fauna, does not belong to the inermis-group. 5. - The populations of the endemic Leuctra kempnyi show important morphological variations within the Pyrenees. © Masson, 1968.