The large branchiopod, Triops cancriformis simplex (Gihi, 1921) (Crustacea: Notostraca) in temporary rain pools, recorded for the first time in Taif-KSA.

The present species Triops cancriformis simplex was not recorded in Taif and Kingdom of Saudi Arabia before. The present work is a confirmatory study to indicate the identity of this species in the ephemeral freshwater bodies in Taif, KSA and to ascertain that, if there is any other Triops species in the same area or not. Four sites were investigated in Taif governorate; Wadi Al-Arj, Saysed, Jabajeb pool and Ghadeer Al-Banat. The animal was not recorded in the first two sites all the year. The specimens were collected from Jabajeb pool on Al-Hada road and Ghadeer Al-Banat at Al-Roddaf region. No specimens were found in these sites during winter and autumn but they start in late spring and summer. One hundred and seven specimens were collected from both sites in this period. The animal was morphologically described to be distinguished from the other large branchiopods species. The supra-anal plate is absent, the dorsal organ of the present species is rounded, second maxilla is present, no supernumerary spines on apodous rings, the carina of T. c. simplex is smooth without spines in front of its terminal spine and presence of small spines on the furca. [ABSTRACT FROM AUTHOR]