8. Nigrobaetis Novikova & Kluge, 1987

Diagnosis.

1) Antennae located close together with a well-developed carina in between; 2) mouthparts in a hypognathous position giving to the body a curved posture in lateral view; 3) right mandible with a simple robust prostheca; 4) paraproct without protuberance.

Remarks.

The position of the antenna and the general posture in lateral view easily separate Alainites and Nigrobaetis from other genera in Maghreb. Contrary to Alainites, Nigrobaetis presents unmodified paraproct (Fig. 2J) and prostheca (Fig. 2B).

Two species of Nigrobaetis are reported in the Maghreb: Nigrobaetis numidicus ( Soldán & Thomas, 1983) (Fig. 5A) and Nigrobaetis rhithralis ( Soldán & Thomas, 1983) (Fig. 5B). Nigrobaetis rhithralis is widely distributed through the Maghreb from Tunisia to Morocco but is rather restricted and never abundant (El Alami et al. 2000; Godunko et al. 2018).

Nigrobaetis numidicus was originally described from Oued Chiffa, close to Alger at an altitude of 200m. It was most certainly a very rare species there, as only four specimens were collected ( Soldán and Thomas 1983b). Despite being easily recognizable by the smooth distal margin of abdominal tergites and its peculiar tergal pattern (Fig. 5A), this species was never reported from Algeria since its original description; in Morocco it seems to only occur in a few localities of the Middle Atlas and Rif (Zerrouk et al. 2021; El Alami et al. 2022a).