Nyssonini of the Arabian Peninsula with description of six new species (Hymenoptera, Spheciformes, Bembicidae)

The tribe Nyssonini of the family Bembicidae from the Arabian Peninsula is revised, a key to the nine species is provided. A total of 114 specimens have been examined. Newly described are: Brachystegus nemkovi Schmid-Egger & Al Jahdhami (male) from Saudia Arabia, B. samadashanensis Al-Jahdhami & Schmid-Egger (male and female), Brachystegus schneideri Schmid-Egger & Al Jahdhami (male) from Oman, Nysson waleedi Al-Jahdhami & Schmid-Egger (female) from Oman, Nysson woodi Al-Jahdhami & Schmid-Egger (female) from Oman and Saudi Arabia, and Synnevrus mekkahensis Schmid-Egger & Al Jahdhami (male and female) from Saudi Arabia. The genus Synnevrus is restored from synonymy. Synnevrus arabicus (Gadallah & Edmardash, 2023), Synnevrus barrei (Radoszkowski, 1893), and Synnevrus ohli Schmid-Egger, 2011, are transferred from Nysson to Synnevrus. Synnevrus barrei and S. ohli are recorded for the first time for the fauna of Oman and Saudi Arabia.